Escitalopram (Lexapro): Drug Whys
Generic Name: Escitalopram (no generic available – U.S. patent expires March 2012)
Common Brand Name: Lexapro (Forest Laboratories – U.S.)
Popularity: 18th most commonly prescribed drug in 2009 (U.S.)
Class: SSRI (selective serotonin reuptake inhibitor), antidepressant, antianxiety
Treatment Uses — For treatment of generalized anxiety disorder (GAD) and major depressive disorder (MDD). Escitalopram has been used successfully for prevention of depression in recent stroke patients (hemorrhagic and ischemic), treatment of obsessive-compulsive disorder (OCD), panic disorder, and premenstrual dysphoric disorder, as well as mild anxiety combined with depressive disorders.
Escitalopram has also been used successfully to treat trichotillomania (pulling hair out of the scalp) in adult women. It has also been used for treatment of mild dementia-associated agitation in nonpsychotic patients. Interestingly, limited studies of escitalopram in children under 12 have shown no benefits in MDD compared to placebo.
The FDA has also added a Black Box warning (their highest level advisory) to escitalopram stating, "Antidepressants increase the risk of suicidal thinking and behavior in children, adolescents, and young adults (18-24 years of age) with major depressive disorder (MDD) and other psychiatric disorders." Prescribers are cautioned to consider this risk.
Escitalopram is not approved for use in children under 12 years old; however, it is prescribed occasionally in the less than 12-year-old age group. In the U.S., outpatient dispensing of any new or refill antidepressant prescriptions to children, adolescents and young adults must be accompanied by an FDA approved medication guide (see: www.fda.gov/cder/Offices/ODS/medication_guides.htm).
Interestingly, the studies that led to this Black Box warning did not show increased risk of suicide in patients over 24 years old and actually demonstrated a decreased risk in patients aged 65 and older.
Patients of all ages should be monitored closely for changes in behavior, suicidality, or worsening of symptoms when being started on any antidepressant medication. This should continue during the first few months of therapy and after any changes in dosing. Family and friends should be encouraged to communicate changes to the prescriber.
Escitalopram is an SSRI which, as a class of antidepressants, is the agent of choice for mild or moderate depression. Severe depression and depression unresponsive to SSRIs may require use of a much older medication class called tricyclic antidepressants (TCAs), or perhaps MAO inhibitors, bupropion or venlafaxine.
One major advantage, as any older medic can recall, is that SSRIs have a far less lethal overdose profile than TCAs. There is no pattern of evidence that any SSRI is superior to any other.
For generalized anxiety disorder, SSRIs, TCAs, and benzodiazepines are all effective. SSRIs are typically preferred for their lower side effect incidence; several studies have shown better response and less relapses when SSRIs are used.
Dosing and Administration — The recommended initial dose of escitalopram for generalized anxiety disorder or major depressive disorder in adults is 10 milligrams orally once daily, taken either in the morning or evening.
The dose may be increased after a minimum of one week to 20 milligrams daily. Studies of higher doses have shown significantly increased side effects without statistically significant improvement in symptoms.
Escitalopram dosing for children 12 years and older is the same as adult dosing, starting at 10 milligrams orally once daily, taken either in the morning or evening. The dose may be increased to 20 milligrams daily after a minimum of three weeks. There are no data showing any benefits of escitalopram in children under 12.
Food has no effect on absorption or availability of escitalopram in the body; morning or evening dosing appears to offer no distinct advantages. It is recommended that doses be taken at the same time each day.
In patients with mild to moderate renal impairment, no dose adjustments of escitalopram are necessary. Caution should be used in patients with severe renal impairment or renal failure. Since escitalopram is extensively metabolized in the liver, the maximum daily dose of escitalopram in patients with hepatic insufficiency is 10 milligrams daily.
The half-life (a reflection of drug clearance) is reduced by 50 percent in elderly (compared to younger) patients. It is recommended that the maximum daily dose be limited to 10 milligrams in elderly patients.
Overdoses of up to 1,000 milligrams of escitalopram have been reported. Most patients were asymptomatic; those with symptoms recovered without long term effects. Overdoses of escitalopram, like other SSRIs, often involve alcohol and other drugs. As such, any SSRI overdose should raise suspicion of multi-drug involvement.
Symptoms of escitalopram overdose have included seizures, altered levels of consciousness ranging from somnolence to coma, dizziness, hypotension, insomnia, nausea, vomiting, sinus tachycardia, somnolence, and ECG changes (including QT prolongation and extremely rare cases of torsade de pointes). Dialysis is not believed helpful for removal of escitalopram.
Pharmacology/Pharmacokinetics/Stability — Following oral administration, time to peak concentration in the bloodstream for escitalopram is 3 to 6 hours and its half-life (time needed to eliminate half the drug from the body) ranges from 22 to 32 hours.
Traces of a single dose can be found in the body for at least 120 hours. Improvement in symptoms of major depression is usually seen in one to two weeks and within one week for generalized anxiety disorders. Overall improvement usually takes several months or longer.
Escitalopram is extensively metabolized in the liver. The kidneys excrete 18 percent of escitalopram in the urine. Elimination is decreased by 50 percent in the elderly.
Escitalopram is usually well tolerated in pregnancy but poses an unusually high risk to the developing fetus during the third trimester. Neonates exposed to SSRIs late in the third trimester of pregnancy have experienced complications requiring prolonged hospitalization, mechanical ventilation and tube feeding. Clinicians are advised to taper SSRIs during the third trimester.
Escitalopram is excreted in human breast milk and there have been rare reports of harmful effects to breastfeeding infants. Bottle feeding has been recommended and should be continued for five days post discontinuation of escitalopram.
If absolutely necessary to continue escitalopram while nursing, the infant should be monitored for excessive sleepiness, weight loss, and decreased appetite. There are studies that suggest escitalopram can be taken by nursing mothers without harm to infants.
Escitalopram's mechanism of action in the body is thought to be associated with potentiation of neurotransmitter activity in the central nervous system.
Escitalopram comes in 5, 10, and 20 milligram film coated, round tablets and a 1 milligram per milliliter solution. Tablets are imprinted with "FL" on one side and either "5," "10," or "20" on the opposite side. The 10 and 20 milligram tablets are scored. Tablets should be stored at room temperature (between 68 and 77 F) with excursions permitted to 59 to 86 F.
Cautions and Warnings — Aside warnings on worsening of depression and risk of suicide, the most significant warnings pertain to use with monoamine oxidase inhibitors (MAOIs). Once a widely prescribed antidepressant, MAOIs are now uncommon, and reserved for patients who don't respond to newer (and safer) agents.
Use of escitalopram in patients taking or who have taken an MAOI within the past 14 days can lead to a fatal serotonin syndrome. This syndrome resembles malignant hyperthermia with rigidity, extremely high fevers, and a constellation of other physical effects resulting from excessive levels of serotonin in the brain.
A minimum of two weeks separation between use of escitalopram and MAOIs is imperative. Escitalopram should be discontinued at least 14 days prior to starting an MAOI.
Abruptly stopping escitalopram can result in another constellation of distressing symptoms including abnormal movements and sensations. Dosing should be tapered gradually when discontinuing therapy.
If a patient has been taking escitalopram for six weeks or longer, it should be tapered over at least two weeks. If intolerable symptoms occur during tapering of escitalopram, the previous dose should be restarted and tapering done more gradually.
Caution is recommended when using escitalopram in patients with known seizure disorders. Seizures have been reported in patients treated with escitalopram although not many data are available as seizure patients were excluded from clinical trials of the drug.
There is also an increased risk of bleeding with escitalopram, like other SSRIs, especially when used in combination with NSAIDs, aspirin, warfarin or other anticoagulants. Release of serotonin by platelets is an important component of maintaining normal clotting times.
The precise risk when SSRIs are coupled with anticoagulants is difficult to quantify but reportedly ranges from increased bruising and nosebleeds to major hemorrhage.
Suicide risk is a concern in any depressed patient, and with SSRIs, particularly younger patients; initiating treatment does not instantly diminish suicide risk.
Despite newer and safer antidepressants, some 30 to 40 percent of depressed patients fail to obtain remission and suffer continued symptoms or relapse.
Caution is warranted with any high-risk patient until remission of depression occurs. Families and significant others should be advised to closely observe patients for clinical worsening, suicidality, or unusual changes in behavior.
Prescriptions should be written for the smallest quantity of medication needed for good patient care with the thought in mind of minimizing danger from an overdose. With long-term therapy, periodic monitoring of heart rate, blood pressure, serum sodium, liver function, renal function, cholesterol and blood counts is advised.
Important Side Effects and Interactions — Headache is reported by 24 percent of patients, as is nausea (15 to 18 percent), somnolence (4 to 13 percent), xerostomia (dry mouth, by 4 to 9 percent), dizziness (4 to 7 percent), insomnia (7 to 14 percent), fatigue (5 to 8 percent), constipation (2 to 6 percent), abdominal pain or indigestion (2 to 6 percent), diarrhea (6 to 14 percent), excessive sweating (3 to 8 percent). Some 9 to 14 percent of male patients report delayed ejaculation. SSRIs are often prescribed as a treatment for premature ejaculation.
Hyponatremia (low serum sodium levels) have been reported with SSRIs including escitalopram, with an incidence of 0.5 to 25 percent, occurring more commonly during the first two to four weeks of therapy.
Risk factors include higher doses, older age, low body weight, female sex, and simultaneous use of narcotics, diuretics, antipsychotics, and/or oral hypoglycemic drugs. Routine monitoring of serum sodium levels may be wise, especially at the outset of therapy in the elderly.
Currently, there are 132 drugs reported to interact with escitalopram. Of these, none are significant to prehospital and emergency medicine providers except perhaps the increased risk of bleeding when used in combination with anticoagulants.
Average Costs — U.S.
• 5 mg/10 mg/20 mg tablet (brand name Lexapro)*
Patient cost: $3.97 each for 5 mg and $3.60 each for 10 and 20 mg
Large Hospital cost: $3.30 each for 5 mg and $3.43 each for 10 and 20 mg
*Wal Mart® and Target don't include this med in their $4/month programs
1. MICROMEDEX Healthcare Series: Thomson Micromedex, Greenwood Village, Colorado (accessed July, 2011).
2. Albany Medical Center Pharmacy, Albany, New York.