Escitalopram, sold under the brand name Lexapro, causes side effects in a significant number of people, though most are mild and fade within the first two weeks of treatment. The most commonly reported effects include nausea, headache, insomnia, and abdominal pain. Sexual side effects are also common and tend to persist longer. Here’s what to expect, what’s serious, and what you can do about it.
Common Side Effects in the First Few Weeks
The side effects most people notice early on are nausea, headache, abdominal pain, insomnia, and diarrhea. Headache is the single most frequently reported effect in clinical trials. These tend to peak during the first one to two weeks and then decrease in both intensity and frequency as your body adjusts to the medication.
About 4.3% of people in clinical trials stopped taking escitalopram because of side effects, compared to 1.3% on placebo. That means the large majority of people who experience early discomfort find it manageable enough to continue treatment.
Managing Nausea and Sleep Problems
If nausea is bothering you, taking escitalopram with food can help. Eating smaller, more frequent meals and staying hydrated also reduce that queasy feeling. Most people find nausea resolves on its own once the body adjusts.
Insomnia is a bit different because timing matters. Taking your dose in the morning rather than at night can make a noticeable difference. Cutting back on caffeine, especially in the afternoon and evening, also helps. If sleep problems stick around beyond the first few weeks, your prescriber may suggest adding a low-dose sedating medication at bedtime or adjusting your overall treatment plan.
Sexual Side Effects
Sexual side effects are among the most common reasons people consider stopping escitalopram, and they deserve their own discussion because they don’t always resolve the way nausea and headaches do. Estimates of sexual dysfunction with this class of antidepressant range from 22% to 54% of users, with some studies reporting rates as high as 73%.
The effects differ somewhat by sex. Men are more likely to have difficulty achieving erections or reaching orgasm. Women tend to experience reduced sex drive and delayed or difficult orgasm. It’s worth noting that depression itself causes sexual problems in roughly 40% of men and 50% of women, so teasing apart what’s caused by the medication versus the condition can be tricky. If sexual side effects are significant for you, there are strategies your prescriber can try, including dose adjustments or switching medications.
Weight Changes Over Time
Escitalopram’s effect on weight is modest but real, and it shows up gradually. At six months, the average weight gain is about 1.4 pounds. By two years, that increases to roughly 3.6 pounds. These are averages, so some people gain more, some gain less, and some don’t gain at all. Compared to several other antidepressants, escitalopram falls on the lower end of the weight gain spectrum.
Suicidal Thinking in Younger Adults
Escitalopram carries an FDA black box warning about an increased risk of suicidal thinking and behavior in people under 25. The numbers from clinical trials break down by age:
- Under 18: 14 additional cases of suicidal thinking per 1,000 patients treated, compared to placebo
- Ages 18 to 24: 5 additional cases per 1,000 patients
- Ages 25 to 64: 1 fewer case per 1,000 patients (slight protective effect)
- 65 and older: 6 fewer cases per 1,000 patients
This doesn’t mean escitalopram causes suicidal behavior in most young people. It means that close monitoring during the first weeks and months of treatment is especially important for anyone under 25. The risk appears to diminish with age, and in older adults the medication actually appears protective.
Risks for Older Adults
People over 65 face a specific concern that younger adults generally don’t: low sodium levels, a condition called hyponatremia. This class of antidepressant can interfere with how the body regulates sodium. Symptoms range from mild issues like weakness and nausea to serious problems like confusion, unsteadiness, falls, and in rare cases, seizures. In older adults, even mild drops in sodium can contribute to cognitive impairment and increase the risk of falls and fractures. Blood work to monitor sodium levels is a reasonable precaution in the early months of treatment for this age group.
Serotonin Syndrome
Serotonin syndrome is a rare but potentially dangerous reaction that happens when too much serotonin builds up in the body. Escitalopram on its own is unlikely to cause it, but the risk increases substantially when it’s combined with other medications that also raise serotonin levels. This includes certain migraine medications, some pain relievers, the herbal supplement St. John’s wort, and especially older antidepressants called MAO inhibitors.
The hallmarks of serotonin syndrome include muscle twitching or jerking (particularly involuntary rhythmic movements), agitation, heavy sweating, rapid heartbeat, and high body temperature. Symptoms typically come on quickly, within hours of a dose change or adding a new medication. This is a medical emergency. The most important way to prevent it is making sure every prescriber knows everything you’re taking, including supplements and over-the-counter medications.
What Happens When You Stop
Stopping escitalopram abruptly can trigger discontinuation syndrome, sometimes called withdrawal. Common symptoms include “brain zaps” (brief, disorienting electrical-sensation feelings in the head), lethargy, excessive sleepiness, dizziness, and irritability. These aren’t dangerous, but they can be deeply unpleasant and sometimes severe enough that people restart the medication just to make them stop.
Gradual tapering reduces this risk significantly. While conventional tapering works for many people, a meaningful number still experience withdrawal symptoms. Newer approaches use very gradual dose reductions toward the end of the taper. In one documented case, a patient who had previously failed standard tapering successfully discontinued by reducing from 10 mg through progressively smaller steps (5 mg, 3 mg, 1.5 mg, 1 mg, 0.5 mg, 0.25 mg), with each reduction spaced a week apart. The key insight is that the final reductions, from small doses to zero, are often the hardest part, and going slower at that stage makes a real difference.