|
(escitalopram oxalate)
TABLETS/ORAL SOLUTION
Rx Only
DESCRIPTION
LEXAPRO™ (escitalopram
oxalate) is an orally administered selective serotonin reuptake inhibitor
(SSRI). Escitalopram is the pure S-enantiomer (single isomer) of the racemic
bicyclic phthalane derivative citalopram.
Escitalopram oxalate is
designated S-(+)-1-[3-(dimethyl-amino)propyl]-1-(p-fluorophenyl)-5-phthalancarbonitrile
oxalate with the following structural formula:
•C2H2O4
The molecular formula is C20H21FN2O
• C2H2O4
and the molecular weight is 414.40.
Escitalopram oxalate occurs as a fine, white to
slightly-yellow powder and is freely soluble in methanol and dimethyl
sulfoxide (DMSO), soluble in isotonic saline solution, sparingly soluble in
water and ethanol, slightly soluble in ethyl acetate, and insoluble in
heptane.
LEXAPRO (escitalopram oxalate) is available as tablets or
as an oral solution.
LEXAPRO tablets are film-coated, round tablets containing
escitalopram oxalate in strengths equivalent to 5 mg, 10 mg, and 20 mg
escitalopram base. The 10 and 20 mg tablets are scored. The tablets also
contain the following inactive ingredients: talc, croscarmellose sodium,
microcrystalline cellulose/colloidal silicon dioxide, and magnesium stearate.
The film coating contains hypromellose, titanium dioxide, and polyethylene
glycol.
LEXAPRO oral solution contains escitalopram oxalate
equivalent to 1 mg/mL escitalopram base. It also contains the following
inactive ingredients: sorbitol, purified water, citric acid, sodium citrate,
malic acid, glycerin, propylene glycol, methylparaben, propylparaben, and
natural peppermint flavor.
CLINICAL PHARMACOLOGY
Pharmacodynamics
The mechanism of antidepressant action of escitalopram,
the S-enantiomer of racemic citalopram, is presumed to be linked to
potentiation of serotonergic activity in the central nervous system (CNS)
resulting from its inhibition
of CNS neuronal
reuptake of serotonin (5-HT).
In vitro
and
in vivo
studies in animals
suggest that escitalopram is
a highly selective serotonin reuptake inhibitor (SSRI) with minimal effects
on norepinephrine and dopamine neuronal reuptake. Escitalopram is at least
100-fold more potent than the R-enantiomer with respect to inhibition
of 5-HT reuptake and
inhibition of 5-HT neuronal firing rate. Tolerance to a model of
antidepressant effect in rats was not induced
by long-term (up to 5 weeks) treatment with escitalopram. Escitalopram has
no or very low affinity for serotonergic
(5-HT1-7) or other
receptors including alpha- and beta-adrenergic, dopamine (D1-5),
histamine
(H1-3),
muscarinic
(M1-5), and benzodiazepine receptors.
Escitalopram also does not bind to, or has low affinity for, various ion
channels including Na+, K+,
Cl-, and Ca++ channels. Antagonism of muscarinic,
histaminergic, and adrenergic receptors has been hypothesized to be
associated with various anticholinergic, sedative, and cardiovascular side
effects of other psychotropic drugs.
Pharmacokinetics
The single- and multiple-dose
pharmacokinetics of escitalopram are linear and dose-proportional in a dose
range of 10 to 30 mg/day. Biotransformation of escitalopram is mainly
hepatic, with a mean terminal half-life of about 27-32 hours. With
once-daily dosing, steady state plasma concentrations are achieved within
approximately one
week. At steady state,
the extent of accumulation of escitalopram in plasma in young healthy
subjects was 2.2-2.5 times the plasma
concentrations observed after a single dose. The tablet and the oral
solution dosage forms of escitalopram oxalate are bioequivalent.
Absorption and Distribution
Following a single oral dose (20 mg tablet or solution)
of escitalopram, peak blood levels occur at about 5 hours. Absorption of
escitalopram is not affected by food.
The absolute bioavailability of citalopram is about 80%
relative to an intravenous dose, and the volume of distribution of
citalopram is about 12 L/kg. Data specific on escitalopram are unavailable.
The binding of escitalopram to human plasma proteins is
approximately 56%.
Metabolism and Elimination
Following oral
administrations of escitalopram, the fraction of drug recovered in the urine
as escitalopram and S - demethylcitalopram (S-DCT) is about 8% and 10%,
respectively. The oral clearance of escitalopram is 600 mL/min, with
approximately 7% of that due to renal clearance.
Escitalopram is metabolized to S-DCT and S-didemethylcitalopram
(S-DDCT). In humans, unchanged escitalopram is the predominant compound in
plasma. At steady state, the concentration of the escitalopram metabolite
S-DCT in plasma is approximately one-third that of escitalopram. The level
of S-DDCT was not detectable in most subjects.
In vitro
studies show that escitalopram is
at least 7 and 27 times more potent than S - DCT and S-DDCT, respectively,
in the inhibition of serotonin reuptake, suggesting that the metabolites of
escitalopram do not contribute significantly to the antidepressant actions
of escitalopram. S-DCT and S-DDCT also have no or very low affinity for
serotonergic (5-HT1-7)
or other receptors including alpha- and
beta-adrenergic, dopamine (D1-5),
histamine
(H1-3), muscarinic
(M1-5),
and benzodiazepine
receptors. S-DCT and S-DDCT also do not bind to various ion channels
including Na+, K+, Cl-, and Ca++ channels.
In vitro
studies using human liver microsomes indicated that
CYP3A4 and CYP2C19 are the primary isozymes involved in the N-demethylation
of escitalopram.
Population Subgroups
Age - Escitalopram
pharmacokinetics in subjects t 65 years of age were compared to younger
subjects in a single-dose and a multiple-dose study. Escitalopram AUC and
half-life were increased by approximately 50% in elderly subjects, and
Cmax was unchanged. 10 mg is the recommended dose for elderly patients
(see DOSAGE AND ADMINISTRATION).
Gender - In a
multiple-dose study of escitalopram (10 mg/day for 3 weeks) in 18 male (9
elderly and 9 young) and
18 female (9 elderly and 9 young) subjects, there were no differences in
AUC, Cmax,
and half-life between the male and female subjects. No
adjustment of dosage on the basis of gender is needed.
Reduced hepatic function -
Citalopram oral clearance was reduced by 37% and half-life was doubled in
patients with reduced hepatic function compared to normal subjects. 10 mg is
the recommended dose of escitalopram for most hepatically impaired patients
(see DOSAGE AND ADMINISTRATION).
Reduced renal function
- In patients with mild to moderate renal function impairment, oral
clearance of citalopram was reduced by 17%
compared to normal subjects. No adjustment of dosage for such patients is
recommended. No information is available about the pharmacokinetics of
escitalopram in patients with severely reduced renal function (creatinine
clearance < 20 mL/min).
Drug-Drug Interactions
In vitro
enzyme inhibition data
did not reveal an inhibitory effect of escitalopram on CYP3A4, -1A2, -2C9,
-2C19, and -2E1. Based on
in vitro
data, escitalopram would be expected to have little
inhibitory effect on
in vivo
metabolism mediated by these cytochromes. While
in vivo
data to address this question are
limited, results from drug interaction studies suggest that escitalopram, at
a dose of 20 mg, has no 3A4 inhibitory effect and a modest
2D6 inhibitory effect.
See Drug
Interactions
under
PRECAUTIONS for
more detailed information on available drug
interaction data.
Clinical Efficacy Trials
Major Depressive Disorder
The efficacy of
LEXAPRO as a treatment for major depressive disorder was established in
three, 8-week, placebo-controlled studies
conducted in outpatients between 18 and 65 years of age who met DSM-IV
criteria for major depressive disorder. The primary outcome in all three
studies was change from baseline to endpoint in the Montgomery Asberg
Depression Rating Scale (MADRS).
A fixed-dose study compared 10 mg/day LEXAPRO and 20
mg/day LEXAPRO to placebo and 40 mg/day citalopram. The 10 mg/day and 20
mg/day LEXAPRO treatment groups showed significantly greater mean
improvement compared to placebo on the MADRS. The 10 mg and 20 mg LEXAPRO
groups were similar on this outcome measure.
In a second fixed-dose study of 10 mg/day LEXAPRO and
placebo, the 10 mg/day LEXAPRO treatment group showed significantly greater
mean improvement compared to placebo on the MADRS.
In a flexible-dose study, comparing
LEXAPRO, titrated between 10 and 20 mg/day, to placebo and citalopram,
titrated between 20 and 40 mg/day, the LEXAPRO treatment
group showed significantly greater mean improvement compared to placebo on
the MADRS.
Analyses of the
relationship between treatment outcome and age, gender, and race did not
suggest any differential responsiveness on the
basis of these patient characteristics.
In a longer-term trial, 274 patients meeting (DSM-IV)
criteria for major depressive disorder, who had responded during an initial
8-week, open-label treatment phase with LEXAPRO 10 or 20 mg/day, were
randomized to continuation of LEXAPRO at their same dose, or to placebo, for
up to 36 weeks of observation for relapse. Response during the open-label
phase was defined by having a decrease of the MADRS total score to d 12.
Relapse during the double-blind phase was defined as an increase of the
MADRS total score to t 22, or discontinuation due to insufficient clinical
response. Patients receiving continued LEXAPRO experienced a significantly
longer time to relapse over the subsequent 36 weeks compared to those
receiving placebo.
Generalized Anxiety Disorder
The efficacy of LEXAPRO in the
treatment of Generalized Anxiety Disorder (GAD) was demonstrated in three,
8-week,
multicenter, flexible-dose, placebo-controlled studies that compared LEXAPRO
10-20 mg/day to placebo
in outpatients between
18 and 80 years of age who met DSM-IV criteria for GAD. In all three
studies, LEXAPRO showed significantly greater
mean improvement compared to placebo on the Hamilton Anxiety Scale (HAM-A).
There were too few
patients in differing ethnic and age groups to adequately assess whether or
not LEXAPRO has differential effects in these
groups. There was no difference in response to LEXAPRO between men and
women.
INDICATIONS AND USAGE
Major Depressive Disorder
LEXAPRO (escitalopram) is indicated for the treatment of
major depressive disorder.
The efficacy of LEXAPRO in the
treatment of major depressive disorder was established in three, 8-week,
placebo-controlled trials of outpatients whose diagnoses corresponded most
closely to the DSM-IV category of major depressive disorder (see
CLINICAL PHARMACOLOGY).
A major depressive
episode (DSM-IV) implies a prominent and relatively persistent (nearly every
day for at least 2 weeks)
depressed or dysphoric mood that usually interferes with daily functioning,
and includes at least five of the following nine symptoms: depressed mood,
loss of interest in usual activities, significant change in weight
and/or appetite,
insomnia or hypersomnia, psychomotor agitation or retardation, increased
fatigue, feelings of guilt or worthlessness,
slowed thinking or impaired concentration, a suicide attempt or suicidal
ideation.
The efficacy of LEXAPRO in hospitalized patients with
major depressive disorders has not been adequately studied.
The efficacy of LEXAPRO in
maintaining a response, in patients with major depressive disorder who
responded during an 8-week, acute-treatment phase while taking LEXAPRO and
were then observed for relapse during a period of up to 36 weeks, was
demonstrated in a placebo-controlled trial (see
Clinical Efficacy Trials
under CLINICAL PHARMACOLOGY).
Nevertheless, the physician who elects to use LEXAPRO
for extended periods should periodically re-evaluate the long-term
usefulness of the drug for the individual patient (see
DOSAGE AND ADMINISTRATION).
Generalized Anxiety Disorder
LEXAPRO is indicated for the treatment of Generalized
Anxiety Disorder (GAD).
The efficacy of
LEXAPRO was established in three, 8-week, placebo-controlled trials in
patients with GAD (see
CLINICAL PHARMACOLOGY).
Generalized Anxiety Disorder (DSM-IV) is characterized by
excessive anxiety and worry (apprehensive expectation) that is persistent
for at least 6 months and which the person finds difficult to control. It
must be associated with at least 3 of the following symptoms: restlessness
or feeling keyed up or on edge, being easily fatigued, difficulty
concentrating or mind going blank, irritability, muscle tension, and sleep
disturbance.
The efficacy of LEXAPRO in the long-term treatment of
GAD, that is, for more than 8 weeks, has not been systematically evaluated
in controlled trials. The physician who elects to use LEXAPRO for extended
periods should periodically re-evaluate the long-term usefulness of the drug
for the individual patient.
CONTRAINDICATIONS
Concomitant use in patients taking
monoamine oxidase inhibitors (MAOIs) is contraindicated (see
WARNINGS).
LEXAPRO is contraindicated in patients with a
hypersensitivity to escitalopram or citalopram or any of the
inactive ingredients
in LEXAPRO. WARNINGS
Potential for Interaction with Monoamine Oxidase
Inhibitors
In patients receiving serotonin
reuptake inhibitor drugs in combination with a monoamine oxidase
inhibitor (MAOI), there
have been reports of serious, sometimes fatal, reactions including
hyperthermia,
rigidity, myoclonus, autonomic instability with possible rapid fluctuations
of vital signs, and mental status
changes that include
extreme agitation progressing to delirium and coma. These reactions have
also been reported in patients who have recently discontinued SSRI treatment
and have been started on an MAOI. Some cases presented with features
resembling neuroleptic malignant syndrome. Furthermore, limited
animal data on the effects of combined use of SSRIs
and MAOIs suggest that these drugs may act
synergistically to
elevate blood pressure and evoke behavioral excitation. Therefore, it is
recommended that LEXAPRO should not be used in
combination with an MAOI, or within 14 days of discontinuing
treatment with an MAOI.
Similarly, at least 14 days should be allowed after stopping LEXAPRO before
starting an MAOI.
Serotonin syndrome has
been reported in two patients who were concomitantly receiving linezolid, an
antibiotic which is a reversible non-selective
MAOI.
Clinical Worsening and Suicide Risk
Patients with major depressive disorder, both adult and pediatric, may
experience worsening of their
depression and/or the emergence of suicidal ideation
and behavior (suicidality), whether or not they are
taking antidepressant medications, and this risk may
persist until significant remission occurs. Although
there has been a long-standing concern that
antidepressants may have a role in inducing worsening of
depression and the emergence of suicidality in certain
patients, a causal role for antidepressants in inducing
such behaviors has not been established. Nevertheless,
patients being treated with antidepressants
should be observed closely for clinical
worsening and suicidality, especially at the beginning of a
course of drug therapy, or at the time of dose
changes, either increases or decreases. Consideration
should be given to changing the therapeutic regimen,
including possibly discontinuing the medication, in
patients whose depression is persistently worse or
whose emergent suicidality is severe, abrupt in onset, or
was not part of the patient’s presenting symptoms.
Because of the possibility of co-morbidity between
major depressive disorder and other psychiatric and
nonpsychiatric disorders, the
same precautions observed when treating patients with major depressive
disorder should be observed when treating patients
with other psychiatric and nonpsychiatric disorders.
The following symptoms, anxiety, agitation, panic
attacks, insomnia, irritability, hostility (aggressiveness),
impulsivity, akathisia
(psychomotor restlessness), hypomania, and mania, have been reported in
adult and pediatric patients being treated with
antidepressants for major depressive disorder as well as for other
indications, both psychiatric and nonpsychiatric.
Although a causal link between the emergence of such
symptoms and either the worsening of depression and/or
the emergence of suicidal impulses has not been
established, consideration should be given to changing the therapeutic
regimen, including possibly discontinuing the
medication, in patients for whom such symptoms are severe, abrupt in onset,
or were not part of the patient’s presenting
symptoms.
Families and caregivers of patients being treated
with antidepressants for major depressive disorder
or other indications, both
psychiatric and nonpsychiatric, should be alerted about the need to
monitor patients for the emergence of agitation,
irritability, and the other symptoms described
above, as well as the emergence of suicidality, and to report such symptoms
immediately to health-care providers.
Prescriptions for LEXAPRO should be written for the
smallest quantity of tablets consistent with good patient management, in
order to reduce the risk of overdose.
If the decision has been made to discontinue
treatment, medication should be tapered, as rapidly as is
feasible, but with recognition
that abrupt discontinuation can be associated with certain symptoms (see
PRECAUTIONS and
DOSAGE AND ADMINISTRATION, Discontinuation of
Treatment with LEXAPRO,
for a description of the risks of discontinuation of
LEXAPRO).
It should be noted that LEXAPRO is not approved for use
in treating any indications in the pediatric population.
A major depressive episode may be the initial
presentation of bipolar disorder. It is generally believed
(though not established in
controlled trials) that treating such an episode with an antidepressant
alone may increase the likelihood of
precipitation of a mixed/manic episode in patients at risk for bipolar
disorder. Whether any of the symptoms described
above represent such a conversion is unknown. However, prior to
initiating treatment with an antidepressant, patients
should be adequately screened to determine if they are
at risk for bipolar disorder; such screening should
include a detailed psychiatric history, including a family
history of suicide, bipolar disorder, and depression.
It should be noted that LEXAPRO is not approved for
use in treating bipolar depression.
PRECAUTIONS
General
Discontinuation of Treatment with LEXAPRO
During marketing of Lexapro and
other SSRIs and SNRIs (serotonin and norepinephrine reuptake inhibitors),
there have been
spontaneous reports of adverse events occurring upon discontinuation of
these drugs, particularly
when abrupt, including
the following: dysphoric mood, irritability, agitation,
dizziness,
sensory disturbances (e.g., paresthesias such
as electric shock sensations), anxiety, confusion, headache, lethargy,
emotional lability, insomnia, and hypomania. While these events are
generally self-limiting, there have been reports of serious discontinuation
symptoms.
Patients should be monitored for
these symptoms when discontinuing treatment with LEXAPRO. A gradual
reduction in the dose rather than abrupt cessation is recommended whenever
possible. If intolerable symptoms occur following a decrease in the dose or
upon discontinuation of treatment, then resuming the previously prescribed
dose may be considered. Subsequently, the physician may continue decreasing
the dose but at a more gradual rate (see DOSAGE
AND ADMINISTRATION).
Abnormal Bleeding
Published case reports
have documented the occurrence of bleeding episodes in patients treated with
psychotropic drugs that
interfere with serotonin reuptake. Subsequent epidemiological studies, both
of the case-control and cohort design, have demonstrated an association
between use of psychotropic drugs that interfere with serotonin reuptake and
the occurrence of upper gastrointestinal bleeding. In two studies,
concurrent use of a nonsteroidal anti-inflammatory drug (NSAID) or aspirin
potentiated the risk of bleeding (see Drug
Interactions). Although
these studies focused
on upper gastrointestinal bleeding, there is reason to believe that bleeding
at other sites may be similarly potentiated.
Patients should be cautioned regarding the risk of bleeding associated with
the concomitant use of LEXAPRO with NSAIDs, aspirin, or other drugs that
affect coagulation.
Hyponatremia
One case of hyponatremia has been reported in association
with LEXAPRO treatment. Several cases of hyponatremia or SIADH (syndrome of
inappropriate antidiuretic hormone secretion) have been reported in
association with racemic citalopram. All patients with these events have
recovered with discontinuation of escitalopram or citalopram and/or medical
intervention. Hyponatremia and SIADH have also been reported in association
with other marketed drugs effective in the treatment of major depressive
disorder.
Activation of Mania/Hypomania
In placebo-controlled trials of
LEXAPRO in major depressive disorder, activation of mania/hypomania was
reported in one (0.1%) of 715 patients treated with LEXAPRO and in none of
the 592 patients treated with placebo. One additional case of hypomania has
been reported in association with LEXAPRO treatment. Activation of
mania/hypomania has also been reported in a small proportion of patients
with major affective
disorders treated with
racemic citalopram and other marketed drugs effective in the treatment of
major depressive disorder. As with all drugs
effective in the treatment of major depressive disorder, LEXAPRO should be
used cautiously in patients with a history of mania.
Seizures
Although
anticonvulsant effects of racemic citalopram have been observed in animal
studies, LEXAPRO has not
been systematically evaluated in patients with a seizure disorder. These
patients were excluded from clinical studies during the product's
premarketing testing. In clinical trials of LEXAPRO, cases of convulsion
have been
reported in association with LEXAPRO treatment. Like other drugs effective
in the treatment of major depressive disorder,
LEXAPRO should be introduced with care in patients with a history of seizure
disorder.
Interference with Cognitive and Motor Performance
In a study in normal volunteers,
LEXAPRO 10 mg/day did not produce impairment of intellectual function or
psychomotor performance. Because any psychoactive drug may impair judgment,
thinking, or motor skills,
however, patients
should be cautioned about operating hazardous machinery, including
automobiles, until they are reasonably certain
that LEXAPRO therapy does not affect their ability to engage in such
activities.
Use in Patients with Concomitant Illness
LEXAPRO has not been systematically evaluated in patients
with a recent history of myocardial infarction or unstable heart disease.
Patients with these diagnoses were generally excluded from clinical studies
during the product's premarketing testing.
In subjects with hepatic
impairment, clearance of racemic citalopram was decreased and plasma
concentrations were increased. The recommended dose of LEXAPRO in
hepatically impaired patients is 10 mg/day (see
DOSAGE AND ADMINISTRATION).
Because escitalopram is extensively
metabolized, excretion of unchanged drug in urine is a minor route of
elimination. Until
adequate numbers of patients with severe renal impairment have been
evaluated during chronic treatment with
LEXAPRO, however, it should be used with caution in such patients (see
DOSAGE AND ADMINISTRATION).
Information for Patients
Physicians are advised to discuss the following issues
with patients for whom they prescribe LEXAPRO.
In a study in normal volunteers,
LEXAPRO 10 mg/day did not impair psychomotor performance. The effect of
LEXAPRO on psychomotor coordination, judgment, or thinking has not been
systematically examined in
controlled studies.
Because psychoactive drugs may impair judgment, thinking, or motor skills,
patients should be cautioned about operating
hazardous machinery, including automobiles, until they are reasonably
certain that LEXAPRO therapy does not affect their ability to engage in such
activities.
Patients should be told that, although LEXAPRO has not
been shown in experiments with normal subjects to increase the mental and
motor skill impairments caused by alcohol, the concomitant use of LEXAPRO
and alcohol in depressed patients is not advised.
Patients should be made aware that escitalopram is the
active isomer of Celexa (citalopram hydrobromide) and that the two
medications should not be taken concomitantly.
Patients should be
advised to inform their physician if they are taking, or plan to take, any
prescription or over-the-counter drugs, as
there is a potential for interactions.
Patients should be cautioned about the concomitant use of
LEXAPRO and NSAIDs, aspirin, or other drugs that affect coagulation since
the combined use of psychotropic drugs that interfere with serotonin
reuptake and these agents has been associated with an increased risk of
bleeding.
Patients should be
advised to notify their physician if they become pregnant or intend to
become pregnant during therapy.
Patients should be advised to notify their physician if
they are breastfeeding an infant.
While patients may notice improvement with LEXAPRO
therapy in 1 to 4 weeks, they should be advised to continue therapy as
directed.
Patients and their families should be encouraged to
be alert to the emergence of anxiety, agitation, panic
attacks, insomnia,
irritability, hostility, impulsivity, akathisia, hypomania, mania, worsening
of depression, and suicidal ideation,
especially early during antidepressant treatment. Such symptoms should be
reported to the patient’s physician, especially
if they are severe, abrupt in onset, or were not part of the patient’s
presenting symptoms.
Laboratory Tests
There are no specific laboratory tests recommended.
Concomitant Administration with Racemic Citalopram
Citalopram - Since
escitalopram is the active isomer of racemic citalopram (Celexa), the two agents
should not be
coadministered.
Drug Interactions
CNS Drugs - Given the primary CNS effects of escitalopram,
caution should be used when it is taken in combination with other centrally
acting drugs.
Alcohol - Although LEXAPRO did not
potentiate the cognitive and motor effects of alcohol in a clinical trial, as
with other psychotropic medications, the use of alcohol by patients taking
LEXAPRO is not recommended. Monoamine Oxidase Inhibitors (MAOIs) - See
CONTRAINDICATIONS and
WARNINGS.
Drugs That Interfere With Hemostasis (NSAIDs, Aspirin,
Warfarin, etc.)
Serotonin release by platelets plays an
important role in hemostasis. Epidemiological studies of the case-control and
cohort design that have demonstrated an association between use of psychotropic
drugs that interfere with
serotonin reuptake and the
occurrence of upper gastrointestinal bleeding have also shown that concurrent
use of an NSAID or
aspirin potentiated the risk of bleeding. Thus, patients should be cautioned
about the use of such drugs concurrently with
LEXAPRO.
Cimetidine - In subjects
who had received 21 days of 40 mg/day racemic citalopram, combined
administration of 400 mg/day
cimetidine for 8 days resulted in an increase in citalopram AUC and
Cmax
of 43% and 39%, respectively. The clinical significance of these findings
is unknown.
Digoxin - In subjects who had received
21 days of 40 mg/day racemic citalopram, combined administration of
citalopram and digoxin
(single dose of 1 mg) did not significantly affect the pharmacokinetics of
either citalopram or digoxin.
Lithium - Coadministration
of racemic citalopram (40 mg/day for 10 days) and lithium (30 mmol/day for 5
days) had no significant
effect on the pharmacokinetics of citalopram or lithium. Nevertheless, plasma
lithium levels
should be monitored with appropriate adjustment to the lithium dose in
accordance with standard clinical practice. Because
lithium may enhance the serotonergic effects of escitalopram, caution should be
exercised when LEXAPRO and lithium are coadministered.
Sumatriptan - There have been rare postmarketing reports
describing patients with weakness, hyperreflexia, and incoordination following
the use of an SSRI and sumatriptan. If concomitant treatment with sumatriptan
and an SSRI (e.g., fluoxetine, fluvoxamine, paroxetine, sertraline, citalopram,
escitalopram) is clinically warranted, appropriate observation of the patient is
advised.
Theophylline - Combined administration of racemic citalopram
(40 mg/day for 21 days) and the CYP1A2 substrate theophylline (single dose of
300 mg) did not affect the pharmacokinetics of theophylline. The effect of
theophylline on the pharmacokinetics of citalopram was not evaluated.
Warfarin - Administration of 40 mg/day racemic citalopram for
21 days did not affect the pharmacokinetics of warfarin, a CYP3A4 substrate.
Prothrombin time was increased by 5%, the clinical significance of which is
unknown.
Carbamazepine - Combined administration of racemic citalopram
(40 mg/day for 14 days) and carbamazepine (titrated to 400 mg/day for 35 days)
did not significantly affect the pharmacokinetics of carbamazepine, a CYP3A4
substrate. Although trough citalopram plasma levels were unaffected, given the
enzyme-inducing properties of carbamazepine, the possibility that carbamazepine
might increase the clearance of escitalopram should be considered if the two
drugs are coadministered.
Triazolam - Combined
administration of racemic citalopram (titrated to 40 mg/day for 28 days) and the
CYP3A4
substrate triazolam
(single dose of 0.25 mg) did not significantly affect the pharmacokinetics of
either citalopram
or triazolam.
Ketoconazole - Combined administration of racemic citalopram
(40 mg) and ketoconazole (200 mg), a potent CYP3A4 inhibitor, decreased the
Cmax and AUC of ketoconazole by 21% and 10%, respectively, and did not
significantly affect the pharmacokinetics of citalopram.
Ritonavir - Combined
administration of a single dose of ritonavir (600 mg), both a CYP3A4 substrate
and a potent inhibitor of
CYP3A4, and escitalopram (20 mg) did not affect the pharmacokinetics of either
ritonavir or escitalopram.
CYP3A4 and -2C19 Inhibitors -
In vitro
studies indicated that CYP3A4 and -2C19 are the primary
enzymes involved in the metabolism of escitalopram. However, coadministration of
escitalopram (20 mg) and ritonavir (600 mg), a potent inhibitor of CYP3A4, did
not significantly affect the pharmacokinetics of escitalopram.
Because escitalopram is metabolized by multiple enzyme
systems, inhibition of a single enzyme may not appreciably decrease escitalopram
clearance.
Drugs Metabolized by Cytochrome P4502D6
- In vitro studies did
not reveal an inhibitory effect of escitalopram on CYP2D6. In addition, steady
state levels of racemic citalopram were not significantly different in poor
metabolizers and extensive CYP2D6 metabolizers after multiple-dose
administration of citalopram, suggesting
that coadministration, with
escitalopram, of a drug that inhibits CYP2D6, is unlikely to have clinically
significant effects on escitalopram metabolism.
However, there are limited in vivo
data suggesting a modest CYP2D6
inhibitory effect for
escitalopram, i.e., coadministration of escitalopram (20 mg/day for 21 days)
with the tricyclic antidepressant desipramine
(single dose of 50 mg), a substrate for CYP2D6, resulted in a 40% increase in
Cmax and a 100% increase in AUC of desipramine. The clinical
significance of this finding is unknown. Nevertheless, caution is indicated in
the coadministration of escitalopram and drugs metabolized by CYP2D6.
Metoprolol - Administration of 20
mg/day LEXAPRO for 21 days in healthy volunteers resulted in a 50% increase in
Cmax and 82% increase in AUC of the beta-adrenergic blocker
metoprolol (given in a single dose of 100
mg). Increased metoprolol
plasma levels have been associated with decreased cardioselectivity.
Coadministration of LEXAPRO and metoprolol had no
clinically significant effects on blood pressure or heart rate.
Electroconvulsive Therapy (ECT) - There are no clinical
studies of the combined use of ECT and escitalopram.
Carcinogenesis, Mutagenesis, Impairment of Fertility
Carcinogenesis
Racemic citalopram was administered in
the diet to NMRI/BOM strain mice and COBS WI strain rats for 18 and
24 months, respectively.
There was no evidence for carcinogenicity of racemic citalopram in mice
receiving up to 240
mg/kg/day. There was an increased incidence of small intestine carcinoma in rats
receiving 8 or 24 mg/kg/day racemic citalopram. A
no-effect dose for this finding was not established. The relevance of these
findings to humans is unknown.
Mutagenesis
Racemic citalopram was mutagenic in
the in vitro bacterial
reverse mutation assay (Ames test) in 2 of 5 bacterial strains (Salmonella TA98
and TA1 537) in the absence of metabolic activation. It was clastogenic in the
in vitro
Chinese hamster lung cell
assay for chromosomal aberrations in the presence and absence of metabolic
activation. Racemic
citalopram was not mutagenic in the
in vitro
mammalian forward gene
mutation assay (HPRT) in mouse lymphoma cells or in
a coupled in vitro/in vivo
unscheduled DNA synthesis (UDS) assay in rat liver. It was
not clastogenic in the in vitro
chromosomal aberration assay in human lymphocytes or in
two in vivo mouse
micronucleus assays.
Impairment of Fertility
When racemic citalopram was
administered orally to 16 male and 24 female rats prior to and throughout mating
and gestation at
doses of 32, 48, and 72 mg/kg/day, mating was decreased at all doses, and
fertility was decreased at doses t 32 mg/kg/day.
Gestation duration was increased at 48 mg/kg/day.
Pregnancy
Pregnancy Category C
In a rat embryo/fetal development
study, oral administration of escitalopram (56, 112, or 150 mg/kg/day) to
pregnant animals during the
period of organogenesis resulted in decreased fetal body weight and associated
delays in ossification at the two higher doses
(approximately t 56 times the maximum recommended human dose [MRHD] of 20 mg/day
on a body surface area [mg/m2] basis). Maternal toxicity (clinical
signs and decreased
body weight gain and food consumption), mild at 56 mg/kg/day, was present at all
dose levels. The developmental no-effect dose of 56
mg/kg/day is approximately 28 times the MRHD on a mg/m2 basis. No
teratogenicity was observed at any of the doses tested (as high as 75 times the
MRHD on a mg/m2 basis).
When female rats were treated with escitalopram (6, 12, 24,
or 48 mg/kg/day) during pregnancy and through weaning, slightly increased
offspring mortality and growth retardation were noted at 48 mg/kg/day which is
approximately 24 times the MRHD on a mg/m2 basis. Slight maternal
toxicity (clinical signs and decreased body weight gain and food consumption)
was seen at this dose. Slightly increased offspring mortality was seen at 24
mg/kg/day. The no-effect dose was 12 mg/kg/day which is approximately 6 times
the MRHD on a mg/m2 basis.
In animal reproduction studies, racemic citalopram has been
shown to have adverse effects on embryo/fetal and postnatal development,
including teratogenic effects, when administered at doses greater than human
therapeutic doses.
In two rat embryo/fetal
development studies, oral administration of racemic citalopram (32, 56, or 112
mg/kg/day)
to pregnant animals during
the period of organogenesis resulted in decreased embryo/fetal growth and
survival and
an increased incidence of
fetal abnormalities (including cardiovascular and skeletal defects) at the high
dose. This dose was also associated with maternal
toxicity (clinical signs, decreased body weight gain). The developmental
no-effect dose was 56 mg/kg/day. In a rabbit study, no adverse effects on
embryo/fetal development were observed at doses of racemic citalopram of up to
16 mg/kg/day. Thus, teratogenic effects of racemic citalopram were observed at a
maternally toxic dose in the rat and were not observed in the rabbit.
When female rats were treated with
racemic citalopram (4.8, 12.8, or 32 mg/kg/day) from late gestation through
weaning, increased
offspring mortality during the first 4 days after birth and persistent offspring
growth retardation
were observed at the highest dose. The no-effect dose was 12.8 mg/kg/day.
Similar effects on offspring mortality and growth
were seen when dams were treated throughout gestation and early lactation at
doses t 24 mg/kg/day. A no-effect dose was not determined in that study.
There are no adequate and well-controlled studies in pregnant
women; therefore, escitalopram should be used during pregnancy only if the
potential benefit justifies the potential risk to the fetus.
Pregnancy-Nonteratogenic Effects
Neonates exposed to LEXAPRO and other
SSRIs or SNRIs, late in the third trimester, have developed
complications requiring
prolonged hospitalization, respiratory support, and tube feeding. Such
complications can arise immediately upon delivery.
Reported clinical findings have included respiratory distress, cyanosis, apnea,
seizures,
temperature instability, feeding difficulty, vomiting, hypoglycemia, hypotonia,
hypertonia, hyperreflexia,
tremor, jitteriness,
irritability, and constant crying. These features are consistent with either a
direct toxic effect of
SSRIs and SNRIs or,
possibly, a drug discontinuation syndrome. It should be noted that, in some
cases, the clinical picture is consistent with
serotonin syndrome (see WARNINGS).
When treating a pregnant woman with
LEXAPRO during the third trimester, the physician should carefully consider the
potential risks and benefits of treatment (see
DOSAGE AND ADMINISTRATION).
Labor and Delivery
The effect of LEXAPRO on labor and delivery in humans is
unknown.
Nursing Mothers
Racemic citalopram, like many other
drugs, is excreted in human breast milk. There have been two reports of infants
experiencing excessive somnolence, decreased feeding, and weight loss in
association with breastfeeding from a citalopram-treated mother; in one case,
the infant was reported to recover completely upon
discontinuation of
citalopram by its mother and, in the second case, no follow-up information was
available. The decision whether to continue or
discontinue either nursing or LEXAPRO therapy should take into account the risks
of citalopram exposure for the infant and the benefits of LEXAPRO treatment for
the mother.
Pediatric Use
Safety and effectiveness in pediatric
patients have not been established (see
WARNINGS-Clinical Worsening and Suicide Risk.
Geriatric Use
Approximately 6% of the 1144 patients
receiving escitalopram in controlled trials of LEXAPRO in major
depressive disorder and GAD
were 60 years of age or older; elderly patients in these trials received daily
doses of LEXAPRO between 10 and 20 mg. The number
of elderly patients in these trials was insufficient to adequately
assess for possible
differential efficacy and safety measures on the basis of age. Nevertheless,
greater sensitivity of some elderly individuals to
effects of LEXAPRO cannot be ruled out.
In two pharmacokinetic
studies, escitalopram half-life was increased by approximately 50% in elderly
subjects as compared to young
subjects and Cmax
was unchanged (see
CLINICAL PHARMACOLOGY). 10 mg/day is the
recommended dose for elderly patients (see DOSAGE
AND ADMINISTRATION).
Of 4422 patients in
clinical studies of racemic citalopram, 1357 were 60 and over, 1034 were 65 and
over, and 457 were 75 and over. No overall
differences in safety or effectiveness were observed between these subjects and
younger subjects, and other reported clinical experience has not identified
differences in responses between the elderly and younger patients, but again,
greater sensitivity of some elderly individuals cannot be ruled out.
ADVERSE REACTIONS
Adverse event information for LEXAPRO was collected from
715 patients with major depressive disorder who were exposed to escitalopram and
from 592 patients who were exposed to placebo in double-blind, placebo-controlled
trials. An additional 284 patients with major depressive disorder were newly
exposed to escitalopram in open-label trials. The
adverse event information for LEXAPRO in patients with GAD was collected from
429 patients exposed to escitalopram and from 427 patients exposed to placebo in
double-blind, placebo-controlled trials.
Adverse events during
exposure were obtained primarily by general inquiry and recorded by clinical
investigators
using terminology of their
own choosing. Consequently, it is not possible to provide a meaningful estimate
of the proportion of
individuals experiencing adverse events without first grouping similar types of
events into a smaller
number of standardized event categories. In the tables and tabulations that
follow, standard World Health Organization (WHO) terminology has been used to
classify reported adverse events.
The stated frequencies of adverse
events represent the proportion of individuals who experienced, at least once, a
treatment-emergent
adverse event of the type listed. An event was considerereatment-emergent if
it occurred for the first time or worsened while
receiving therapy following baseline evaluation.
Adverse Events Associated with Discontinuation of Treatment
Major Depressive Disorder
Among the 715 depressed patients who
received LEXAPRO in placebo-controlled trials, 6% discontinued
treatment due to an adverse
event, as compared to 2% of 592 patients receiving placebo. In two fixed-dose
studies, the rate of discontinuation for adverse
events in patients receiving 10 mg/day LEXAPRO was not significantly different
from the rate of discontinuation for adverse events in patients receiving
placebo. The rate of discontinuation for adverse events in patients assigned to
a fixed dose of 20 mg/day LEXAPRO was 10%, which was significantly different
from the rate of discontinuation for adverse events in patients receiving 10
mg/day LEXAPRO (4%)
and placebo (3%). Adverse events that were associated with the discontinuation
of at least 1% of patients treated with LEXAPRO,
and for which the rate was at least twice that of placebo, were nausea (2%) and
ejaculation disorder (2% of male patients).
Generalized Anxiety Disorder
Among the 429 GAD patients who received LEXAPRO 10-20 mg/day
in placebo-controlled trials, 8% discontinued treatment due to an adverse event,
as compared to 4% of 427 patients receiving placebo. Adverse events that were
associated with the discontinuation of at least 1% of patients treated with
LEXAPRO, and for which the rate was at least twice the placebo rate, were nausea
(2%), insomnia (1%), and fatigue (1%).
Incidence of Adverse Events in Placebo-Controlled Clinical
Trials
Major Depressive Disorder
Table 1 enumerates the incidence, rounded to the nearest
percent, of treatment-emergent adverse events that occurred among 715 depressed
patients who received LEXAPRO at doses ranging from 10 to 20 mg/day in
placebo-controlled trials. Events included are those occurring in 2% or more of
patients treated with LEXAPRO and for which the incidence in patients treated
with LEXAPRO was greater than the incidence in placebo-treated patients.
The prescriber should be
aware that these figures can not be used to predict the incidence of adverse
events in the course of usual
medical practice where patient characteristics and other factors differ from
those which prevailed
in the clinical trials.
Similarly, the cited frequencies cannot be compared with figures obtained from
other clinical investigations involving different
treatments, uses, and investigators. The cited figures, however, do provide the
prescribing physician with some basis for estimating the relative contribution
of drug and non-drug factors to the adverse event incidence rate in the
population studied.
The most commonly observed adverse
events in LEXAPRO patients (incidence of approximately 5% or greater and
approximately twice the incidence in placebo patients) were insomnia,
ejaculation disorder (primarily ejaculatory delay), nausea, sweating increased,
fatigue, and somnolence (see TABLE 1).
TABLE 1
Treatment-Emergent Adverse Events:
Incidence in Placebo-Controlled Clinical
Trials for
Major Depressive Disorder*
(Percentage of Patients
Reporting Event)
Body System /
LEXAPRO
Placebo
Adverse Event
(N=715)
(N=592)
|
Autonomic Nervous
System Disorders
Dry Mouth
|
6%
|
5%
|
|
Sweating Increased
|
5%
|
2%
|
|
Central & Peripheral
Nervous System Disorders
Dizziness
|
5%
|
3%
|
|
Gastrointestinal Disorders
Nausea
|
15%
|
7%
|
|
Diarrhea
|
8%
|
5%
|
|
Constipation
|
3%
|
1%
|
|
Indigestion
|
3%
|
1%
|
|
Abdominal Pain
|
2%
|
1%
|
|
General
Influenza-like Symptoms
|
5%
|
4%
|
|
Fatigue
|
5%
|
2%
|
|
Psychiatric Disorders
Insomnia
|
9%
|
4%
|
|
Somnolence
|
6%
|
2%
|
|
Appetite Decreased
|
3%
|
1%
|
|
Libido Decreased
|
3%
|
1%
|
|
Respiratory System
Disorders
Rhinitis
|
5%
|
4%
|
|
Sinusitis
|
3%
|
2%
|
|
Urogenital
Ejaculation Disorder1,2
|
9%
|
<1%
|
|
Impotence2
|
3%
|
<1%
|
|
Anorgasmia3
|
2%
|
<1%
|
*Events reported by at least 2% of patients treated with
LEXAPRO are reported, except for the following events which had an incidence on
placebo t LEXAPRO: headache, upper respiratory tract infection, back pain,
pharyngitis, inflicted injury, anxiety.
1Primarily
ejaculatory delay.
2Denominator
used was for males only (N=225 LEXAPRO; N=1 88 placebo).
3Denominator
used was for females only (N=490 LEXAPRO; N=404 placebo).
Generalized Anxiety Disorder
Table 2 enumerates the incidence,
rounded to the nearest percent of treatment-emergent adverse events that
occurred among 429 GAD
patients who received LEXAPRO 10 to 20 mg/day in placebo-controlled trials.
Events included are those occurring in 2% or more
of patients treated with LEXAPRO and for which the incidence in patients treated
with LEXAPRO was greater than the incidence in placebo-treated patients.
The most commonly observed adverse
events in LEXAPRO patients (incidence of approximately 5% or greater and
approximately twice the incidence in placebo patients) were nausea, ejaculation
disorder (primarily ejaculatory delay), insomnia, fatigue, decreased libido, and
anorgasmia (see TABLE 2).
|
TABLE 2
Treatment-Emergent Adverse Events:
Incidence in Placebo-Controlled
Clinical Trials for Generalized
Anxiety Disorder*
(Percentage of Patients Reporting
Event)
|
|
Body System /
|
LEXAPRO
|
Placebo
|
|
Adverse Event
|
(N=429)
|
(N=427)
|
|
Autonomic Nervous System Disorders
Dry Mouth
|
9%
|
5%
|
|
Sweating Increased
|
4%
|
1%
|
|
Central & Peripheral
Nervous System Disorders
|
|
|
|
Headache
|
24%
|
17%
|
|
|
Paresthesia
|
2%
|
1%
|
|
|
Gastrointestinal Disorders
Nausea
|
18%
|
8%
|
|
|
Diarrhea
|
8%
|
6%
|
|
|
Constipation
|
5%
|
4%
|
|
|
Indigestion
|
3%
|
2%
|
|
|
Vomiting
|
3%
|
1%
|
|
|
Abdominal Pain
|
2%
|
1%
|
|
|
Flatulence
|
2%
|
1%
|
|
|
Toothache
|
2%
|
0%
|
|
|
General
Fatigue
|
8%
|
2%
|
|
|
Influenza-like Symptoms
|
5%
|
4%
|
|
|
Musculoskeletal
Neck/Shoulder Pain
|
3%
|
1%
|
|
|
Psychiatric Disorders
Somnolence
|
13%
|
7%
|
|
|
Insomnia
|
12%
|
6%
|
|
|
Libido Decreased
|
7%
|
2%
|
|
|
Dreaming Abnormal
|
3%
|
2%
|
|
|
Appetite Decreased
|
3%
|
1%
|
|
|
Lethargy
|
3%
|
1%
|
|
|
Yawning
|
2%
|
1%
|
|
|
Urogenital
Ejaculation Disorder1,2
|
14%
|
2%
|
|
|
Anorgasmia3
|
6%
|
<1%
|
|
|
Menstrual Disorder
|
2%
|
1%
|
|
|
|
|
|
|
|
|
*Events reported by at least 2% of patients treated with
LEXAPRO are reported, except for the following events which had an incidence on
placebo t LEXAPRO: inflicted injury, dizziness, back pain, upper respiratory
tract infection, rhinitis, pharyngitis.
1Primarily
ejaculatory delay.
2Denominator
used was for males only (N=182 LEXAPRO; N=195 placebo).
3Denominator
used was for females only (N=247 LEXAPRO; N=232 placebo).
Dose Dependency of Adverse Events
The potential dose dependency of common
adverse events (defined as an incidence rate of t5% in either the 10 mg or 20 mg
LEXAPRO groups) was examined on the basis of the combined incidence of adverse
events in two fixed-dose trials. The overall incidence rates of adverse events
in 10 mg LEXAPRO-treated patients (66%) was similar to that of the
placebo-treated patients (6 1%), while the incidence rate in 20 mg/day
LEXAPRO-treated patients was greater (86%). Table 3 shows common adverse events
that occurred in the 20 mg/day LEXAPRO
group with an incidence
that was approximately twice that of the 10 mg/day LEXAPRO group and
approximately twice that of the placebo group.
TABLE 3
Incidence of
Common Adverse Events* in Patients with Major
Depressive Disorder Receiving Placebo, 10 mg/day LEXAPRO, or
20 mg/day LEXAPRO
|
Adverse Event
|
Placebo
|
10 mg/day
|
20 mg/day
|
|
|
|
(N=311)
|
LEXAPRO
|
LEXAPRO
|
|
|
|
|
(N=310)
|
(N=125)
|
|
|
Insomnia
|
4%
|
7%
|
14%
|
|
|
Diarrhea
|
5%
|
6%
|
14%
|
|
|
Dry Mouth
|
3%
|
4%
|
9%
|
|
|
Somnolence
|
1%
|
4%
|
9%
|
|
Dizziness
|
2%
|
4%
|
7%
|
|
Sweating Increased
|
<1%
|
3%
|
8%
|
|
Constipation
|
1%
|
3%
|
6%
|
|
Fatigue
|
2%
|
2%
|
6%
|
|
Indigestion
|
1%
|
2%
|
6%
|
|
*Adverse events with an incidence rate of at
|
least 5% in either of the LEXAPRO
|
groups and with an incidence
|
|
rate in the 20 mg/day LEXAPRO group that
and the placebo group.
|
was approximately twice that of the
|
10 mg/day LEXAPRO group
|
|
|
|
|
|
|
|
|
|
Male and Female Sexual Dysfunction with SSRIs
Although changes in sexual desire, sexual performance, and
sexual satisfaction often occur as manifestations of a psychiatric disorder,
they may also be a consequence of pharmacologic treatment. In particular, some
evidence suggests that SSRIs can cause such untoward sexual experiences.
Reliable estimates of the incidence and
severity of untoward experiences involving sexual desire, performance,
and satisfaction are
difficult to obtain, however, in part because patients and physicians may be
reluctant to discuss them. Accordingly, estimates
of the incidence of untoward sexual experience and performance cited in product
labeling are likely to underestimate their actual incidence.
Table 4 shows the incidence rates of sexual side effects in
patients with major depressive disorder and GAD in placebo-controlled trials.
TABLE 4
Incidence of Sexual Side Effects in
Placebo-Controlled Clinical Trials
Adverse Event
LEXAPRO
Placebo
|
|
|
In Males Only
|
|
|
|
(N=407)
|
|
(N=383)
|
|
Ejaculation Disorder
(primarily ejaculatory delay)
|
12%
|
|
1%
|
|
Libido Decreased
|
6%
|
|
2%
|
|
Impotence
|
2%
|
|
<1%
|
|
|
(N=737)
|
In Females Only
|
(N=636)
|
|
Libido Decreased
|
3%
|
|
1%
|
|
Anorgasmia
|
3%
|
|
<1%
|
There are no adequately
designed studies examining sexual dysfunction with escitalopram treatment. Priapism has been reported with all SSRIs.
While it is difficult to know the precise risk of sexual
dysfunction associated with the use of SSRIs, physicians should routinely
inquire about such possible side effects.
Vital Sign Changes
LEXAPRO and placebo groups were compared with respect to (1)
mean change from baseline in vital signs (pulse, systolic blood pressure, and
diastolic blood pressure) and (2) the incidence of patients meeting criteria for
potentially clinically significant changes from baseline in these variables.
These analyses did not reveal any clinically important changes in vital signs
associated with LEXAPRO treatment. In addition, a comparison of supine and
standing vital sign measures in subjects receiving LEXAPRO indicated that
LEXAPRO treatment is not associated with orthostatic changes.
Weight Changes
Patients treated with LEXAPRO in controlled trials did not
differ from placebo-treated patients with regard to clinically important change
in body weight.
Laboratory Changes
LEXAPRO and placebo groups were compared with respect to (1)
mean change from baseline in various serum
chemistry, hematology, and urinalysis variables, and (2) the
incidence of patients meeting criteria for potentially clinically significant
changes from baseline in these variables. These analyses revealed no clinically
important changes in laboratory test parameters associated with LEXAPRO
treatment.
ECG Changes
Electrocardiograms from LEXAPRO (N=625), racemic citalopram
(N=351), and placebo (N=527) groups were compared with respect to (1) mean
change from baseline in various ECG parameters and (2) the incidence of patients
meeting criteria for potentially clinically significant changes from baseline in
these variables. These analyses revealed (1) a decrease in heart rate of 2.2 bpm
for LEXAPRO and 2.7 bpm for racemic citalopram, compared to an increase of 0.3
bpm for placebo and (2) an increase in QTc interval of 3.9 msec for LEXAPRO and
3.7 msec for racemic citalopram, compared to 0.5 msec for placebo. Neither
LEXAPRO nor racemic citalopram were associated with the development of
clinically significant ECG abnormalities.
Other Events Observed During the Premarketing Evaluation of
LEXAPRO
Following is a list of WHO terms that
reflect treatment-emergent adverse events, as defined in the introduction to
the
ADVERSE REACTIONS
section, reported by the
1428 patients treated with LEXAPRO for periods of up to
one year in double-blind or open-label clinical trials during its premarketing
evaluation. All reported events are included except those already listed in
Tables 1 & 2, those occurring in only one patient, event terms that are so
general as to be uninformative, and those that are unlikely to be drug related.
It is important to emphasize that, although the events reported occurred during
treatment with LEXAPRO, they were not necessarily caused by it.
Events are further categorized by body
system and listed in order of decreasing frequency according to the following
definitions: frequent adverse events are those occurring on one or more
occasions in at least 1/100 patients; infrequent adverse events are those
occurring in less than 1/100 patients but at least 1/1 000 patients.
Cardiovascular - Frequent:
palpitation, hypertension.
Infrequent: bradycardia, tachycardia, ECG abnormal,
flushing, varicose vein.
Central and Peripheral Nervous System
Disorders - Frequent:
light-headed feeling, migraine. Infrequent:
tremor, vertigo, restless legs, shaking, twitching,
dysequilibrium, tics, carpal tunnel syndrome, muscle contractions involuntary,
sluggishness, coordination abnormal, faintness, hyperreflexia, muscular tone
increased. Gastrointestinal Disorders - Frequent:
heartburn, abdominal cramp, gastroenteritis.
Infrequent: gastroesophageal
reflux, bloating, abdominal discomfort, dyspepsia, increased stool frequency,
belching, gastritis, hemorrhoids, gagging, polyposis gastric, swallowing
difficult.
General -
Frequent: allergy, pain in limb, fever, hot
flushes, chest pain. Infrequent:
edema of extremities, chills, tightness of chest, leg
pain, asthenia, syncope, malaise, anaphylaxis, fall.
Hemic and Lymphatic Disorders -
Infrequent: bruise, anemia,
nosebleed, hematoma, lymphadenopathy cervical. Metabolic and Nutritional
Disorders - Frequent:
increased weight. Infrequent:
decreased weight, hyperglycemia, thirst, bilirubin
increased, hepatic enzymes increased, gout, hypercholesterolemia.
Musculoskeletal System Disorders -
Frequent: arthralgia,
myalgia. Infrequent:
jaw stiffness, muscle cramp, muscle stiffness, arthritis, muscle weakness, back
discomfort, arthropathy, jaw pain, joint stiffness. Psychiatric Disorders -
Frequent: appetite
increased, lethargy, irritability, concentration impaired.
Infrequent: jitteriness,
panic reaction, agitation, apathy, forgetfulness, depression aggravated,
nervousness, restlessness
aggravated, suicide
attempt, amnesia, anxiety attack, bruxism, carbohydrate craving, confusion,
depersonalization,
disorientation, emotional lability, feeling unreal, tremulousness nervous,
crying abnormal, depression, excitability, auditory
hallucination, suicidal tendency.
Reproductive Disorders/Female* -
Frequent: menstrual cramps,
menstrual disorder. Infrequent:
menorrhagia, breast neoplasm, pelvic inflammation,
premenstrual syndrome, spotting between menses.
*% based on female subjects only: N= 905
Respiratory System Disorders -
Frequent:
bronchitis, sinus
congestion, coughing, nasal congestion, sinus headache.
Infrequent: asthma, breath
shortness, laryngitis, pneumonia, tracheitis.
Skin and Appendages Disorders -
Frequent: rash.
Infrequent: pruritus, acne,
alopecia, eczema, dermatitis, dry skin, folliculitis, lipoma, furunculosis, dry
lips, skin nodule.
Special Senses -
Frequent: vision blurred,
tinnitus. Infrequent:
taste alteration, earache, conjunctivitis, vision abnormal, dry eyes, eye
irritation, visual disturbance, eye infection, pupils dilated, metallic taste.
Urinary System Disorders - Frequent:
urinary frequency, urinary tract infection.
Infrequent: urinary urgency,
kidney stone, dysuria, blood in urine.
Events Reported Subsequent to the Marketing of Racemic
Citalopram and Escitalopram
Although no causal relationship to
racemic citalopram or escitalopram treatment has been found, the following
adverse events have been reported to have occurred in patients and to be
temporally associated with racemic citalopram treatment and with escitalopram
treatment during postmarketing experience and were not observed
during the premarketing
evaluation of citalopram or escitalopram: acute renal failure, angioedema, toxic
epidermal necrolysis, gastrointestinal hemorrhage,
grand mal seizures (or convulsions), neuroleptic malignant syndrome,
pancreatitis, QT prolongation, rhabdomyolysis, serotonin syndrome,
thrombocytopenia, torsades de pointes.
Events Reported Subsequent to the Marketing of Racemic
Citalopram (not observed during the postmarketing experience with escitalopram)
Although no causal relationship to
racemic citalopram treatment has been found, the following adverse events
have been reported to have
occurred in patients and to be temporally associated with racemic citalopram
treatment and were
not observed during the premarketing evaluation of citalopram: akathisia,
allergic reaction, anaphylaxis, choreoathetosis,
delirium, dyskinesia, ecchymosis, erythema multiforme, hemolytic anemia, hepatic
necrosis, myoclonus, nystagmus, priapism, prolactinemia, prothrombin decreased,
spontaneous abortion, thrombosis, and ventricular arrhythmia.
Events Reported Subsequent to the Marketing of Escitalopram
(not observed during the postmarketing experience with citalopram)
Although no causal
relationship to escitalopram treatment has been found, the following adverse
events have been reported to have occurred in
patients and to be temporally associated with escitalopram treatment and were
not observed during the premarketing evaluation of escitalopram: aggression,
atrial fibrillation, seizures, diplopia, dystonia, extrapyramidal disorders,
abnormal gait, visual hallucinations, hepatitis, hypotension, myocardial
infarction, orthostatic hypotension, pulmonary embolism, SIADH, ventricular
tachycardia.
DRUG ABUSE AND DEPENDENCE
Controlled Substance Class
LEXAPRO is not a
controlled substance.
Physical and Psychological Dependence
Animal studies suggest that the abuse
liability of racemic citalopram is low. LEXAPRO has not been
systematically studied in
humans for its potential for abuse, tolerance, or physical dependence. The
premarketing
clinical experience with LEXAPRO did not reveal any drug-seeking behavior.
However, these observations were not systematic and
it is not possible to predict on the basis of this limited experience the extent
to which a CNS-active drug will be misused, diverted, and/or abused once
marketed. Consequently, physicians should carefully
evaluate LEXAPRO patients
for history of drug abuse and follow such patients closely, observing them for
signs of misuse or abuse (e.g., development of
tolerance, incrementations of dose, drug-seeking behavior).
OVERDOSAGE
Human Experience
There have been reports of LEXAPRO
overdose involving doses of up to 600 mg. All patients recovered and no symptoms
associated with the overdoses were reported. In clinical trials of racemic
citalopram, there were no
reports of fatal citalopram
overdose involving overdoses of up to 2000 mg. During the postmarketing
evaluation of
citalopram, like other SSRIs, a fatal outcome in a patient who has taken an
overdose of citalopram has been rarely reported.
Postmarketing reports of
drug overdoses involving citalopram have included 12 fatalities, 10 in
combination with
other drugs and/or alcohol
and 2 with citalopram alone (3920 mg and 2800 mg), as well as non-fatal
overdoses of
up to 6000 mg. Symptoms most often accompanying citalopram overdose, alone or in
combination with other
drugs and/or alcohol,
included
dizziness,
sweating, nausea, vomiting, tremor, somnolence, sinus tachycardia, and
convulsions. In more rare cases, observed symptoms included amnesia, confusion,
coma, hyperventilation,
cyanosis, rhabdomyolysis,
and ECG changes (including QTc prolongation, nodal rhythm, ventricular
arrhythmia, and one possible case of torsades de
pointes).
Management of Overdose
Establish and maintain an airway to
ensure adequate ventilation and oxygenation. Gastric evacuation by lavage
and use of activated
charcoal should be considered. Careful observation and cardiac and vital sign
monitoring are recommended, along with general
symptomatic and supportive care. Due to the large volume of distribution of
escitalopram, forced diuresis, dialysis, hemoperfusion, and exchange transfusion
are unlikely to be of benefit. There are no specific antidotes for LEXAPRO.
In managing overdosage, consider the possibility of
multiple-drug involvement. The physician should consider contacting a poison
control center for additional information on the treatment of any overdose.
DOSAGE AND ADMINISTRATION
Major Depressive Disorder
Initial Treatment
The recommended dose of LEXAPRO is 10
mg once daily. A fixed-dose trial of LEXAPRO demonstrated the
effectiveness of both 10 mg
and 20 mg of LEXAPRO, but failed to demonstrate a greater benefit of 20 mg over
10 mg (see Clinical
Efficacy Trials under
CLINICAL PHARMACOLOGY). If the dose is increased to
20 mg, this should occur after a minimum of one week.
LEXAPRO should be
administered once daily, in the morning or evening, with or without food.
Special Populations
10 mg/day is the recommended dose for most elderly patients
and patients with hepatic impairment.
No dosage adjustment is necessary for patients with mild or
moderate renal impairment. LEXAPRO should be used with caution in patients with
severe renal impairment.
Treatment of Pregnant Women During the Third Trimester
Neonates exposed to LEXAPRO and other
SSRIs or SNRIs, late in the third trimester, have developed complications
requiring prolonged hospitalization, respiratory support, and tube feeding (see
PRECAUTIONS). When
treating pregnant women with LEXAPRO during the third trimester, the physician
should carefully consider the potential risks and benefits of treatment. The
physician may consider tapering LEXAPRO in the third trimester.
Maintenance Treatment
It is generally agreed that acute
episodes of major depressive disorder require several months or longer of
sustained pharmacological therapy beyond response to the acute episode.
Systematic evaluation of continuing LEXAPRO 10 or 20 mg/day for periods of up to
36 weeks in patients with major depressive disorder who responded while taking
LEXAPRO during an 8-week, acute-treatment phase demonstrated a benefit of such
maintenance treatment (see Clinical Efficacy Trials
under CLINICAL
PHARMACOLOGY). Nevertheless, patients should be
periodically reassessed to determine the need for maintenance treatment.
Generalized Anxiety Disorder
Initial Treatment
The recommended starting
dose of LEXAPRO is 10 mg once daily. If the dose is increased to 20 mg, this
should occur after a minimum of one week.
LEXAPRO should be administered once daily, in the morning or
evening, with or without food.
Maintenance Treatment
Generalized anxiety
disorder is recognized as a chronic condition. The efficacy of LEXAPRO in the
treatment of GAD beyond 8 weeks has not been
systematically studied. The physician who elects to use LEXAPRO for extended
periods should periodically re-evaluate the long-term usefulness of the drug for
the individual patient.
Discontinuation of Treatment with LEXAPRO
Symptoms associated with
discontinuation of LEXAPRO and other SSRIs and SNRIs have been reported (see
PRECAUTIONS). Patients
should be monitored for these symptoms when discontinuing treatment. A gradual
reduction in the dose rather than abrupt cessation is recommended whenever
possible. If intolerable symptoms occur following a decrease in the dose or upon
discontinuation of treatment, then resuming the previously prescribed dose may
be considered. Subsequently, the physician may continue decreasing the dose but
at a more gradual rate.
Switching Patients To or From a Monoamine Oxidase Inhibitor
At least 14 days should elapse between
discontinuation of an MAOI and initiation of LEXAPRO therapy. Similarly, at
least 14 days should be allowed after stopping LEXAPRO before starting an MAOI
(see CONTRAINDICATIONS
and WARNINGS).
HOW SUPPLIED
5 mg Tablets:
Bottle of 100
NDC # 0456-2005-01
White to off-white, round, non-scored, film-coated. Imprint
"FL" on one side of the tablet and "5" on the other side.
10 mg Tablets:
Bottle of 100
NDC # 0456-2010-01
10 x 10 Unit Dose
NDC # 0456-2010-63
White
to off-white, round, scored, film-coated. Imprint on scored side with "F" on the
left side and "L" on the right side.
Imprint on the non-scored side with "10".
20 mg Tablets:
Bottle of 100
NDC # 0456-2020-0 1
10 x 10 Unit Dose
NDC # 0456-2020-63
White to off-white, round,
scored, film-coated. Imprint on scored side with "F" on the left side and "L" on
the right side.
Imprint on the non-scored side with "20".
Oral Solution:
5 mg/5 mL, peppermint flavor (240 mL) NDC # 0456-2101-08
Store at 25°C (77°F); excursions permitted to 15 - 30°C
(59-86°F).
ANIMAL TOXICOLOGY
Retinal Changes in Rats
Pathologic changes
(degeneration/atrophy) were observed in the retinas of albino rats in the 2-year
carcinogenicity study with
racemic citalopram. There was an increase in both incidence and severity of
retinal pathology in both
male and female rats
receiving 80 mg/kg/day. Similar findings were not present in rats receiving 24
mg/kg/day of racemic
citalopram for two years, in mice receiving up to 240 mg/kg/day of racemic
citalopram for 18 months, or in dogs receiving up
to 20 mg/kg/day of racemic citalopram for one year.
Additional studies to investigate the mechanism for this
pathology have not been performed, and the potential significance of this effect
in humans has not been established.
Cardiovascular Changes in Dogs
In a one-year toxicology study, 5 of 10
beagle dogs receiving oral racemic citalopram doses of 8 mg/kg/day died suddenly
between weeks 17 and 31 following initiation of treatment. Sudden deaths were
not observed in rats at
doses of racemic citalopram
up to 120 mg/kg/day, which produced plasma levels of citalopram and its
metabolites demethylcitalopram and
didemethylcitalopram (DDCT) similar to those observed in dogs at 8 mg/kg/day. A
subsequent
intravenous dosing study demonstrated that in beagle dogs, racemic DDCT caused
QT prolongation, a known risk factor for the
observed outcome in dogs.
|