Lexapro (escitalopram) is a prescription antidepressant used to treat depression and anxiety. It belongs to a class of medications called SSRIs, which work by increasing serotonin levels in the brain. The FDA has approved it specifically for two conditions: major depressive disorder in adults and adolescents aged 12 and older, and generalized anxiety disorder in adults.
FDA-Approved Uses
Lexapro has two official indications. The first is major depressive disorder (MDD), the clinical term for persistent depression that interferes with daily life. It’s one of the few SSRIs approved for adolescents as young as 12, not just adults. The second approved use is generalized anxiety disorder (GAD) in adults, a condition marked by excessive, hard-to-control worry that lasts for months and often comes with physical symptoms like muscle tension, restlessness, and trouble sleeping.
For both conditions, the standard starting dose is 10 mg taken once a day, morning or evening, with or without food. The maximum is 20 mg daily. For adults, a prescriber may increase the dose after one week if needed. For adolescents, that adjustment typically happens after at least three weeks. Older adults and people with liver problems generally stay at 10 mg.
Off-Label Uses
Prescribers frequently use Lexapro for conditions beyond its two FDA-approved indications. This is called off-label prescribing, and it’s a common, legal practice in medicine when a doctor believes the drug is likely to help based on clinical experience or research on related medications.
Off-label uses for Lexapro include obsessive-compulsive disorder (OCD), panic disorder, post-traumatic stress disorder (PTSD), social phobia, body dysmorphic disorder, eating disorders like binge eating and bulimia, premenstrual dysphoric disorder (PMDD), premature ejaculation, and hot flashes associated with menopause. If you’ve been prescribed Lexapro for something other than depression or GAD, that’s likely why.
How It Works in the Brain
Lexapro is a selective serotonin reuptake inhibitor. In practical terms, your brain naturally recycles serotonin after it’s released between nerve cells. Lexapro slows that recycling process, allowing serotonin to stay active longer. Serotonin plays a role in mood regulation, sleep, appetite, and emotional processing, so keeping more of it available can gradually ease symptoms of depression and anxiety.
What makes Lexapro different from older SSRIs like Prozac or Zoloft is its selectivity. It’s considered one of the most targeted SSRIs, meaning it focuses more narrowly on serotonin reuptake and interacts less with other brain systems. This is part of why it tends to have a somewhat cleaner side effect profile than some of its predecessors, though side effects still happen.
How Long It Takes to Work
Lexapro raises serotonin levels within hours of your first dose, but that doesn’t translate to feeling better right away. Your brain needs time to adapt to the new chemical balance. Early signs that the medication is working, like better sleep, more energy, or improved appetite, can show up within one to two weeks.
The core symptoms of depression or anxiety, such as persistent low mood, loss of interest in things you used to enjoy, or constant worry, typically take longer. Full improvement may take six to eight weeks. This is one of the most important things to know if you’re starting the medication: the first few weeks can feel discouraging, and some side effects may appear before the benefits do. Sticking with it through that window is usually necessary to judge whether it’s working.
Common Side Effects
Like all SSRIs, Lexapro comes with a range of possible side effects. Not everyone experiences them, and for many people they’re mild or fade within the first few weeks. But some persist, and it’s worth knowing what to expect.
The most frequently reported side effects across SSRI users include drowsiness or sleepiness (affecting roughly half of users in some studies), sexual dysfunction (reported by over half in naturalistic studies, affecting both men and women), weight gain, dry mouth, fatigue, and nausea. Sleep disturbances go both directions: about 17% of people in clinical trials experienced insomnia, while a similar percentage reported excessive sleepiness, compared to about 8% on placebo.
Sexual side effects deserve special attention because they’re common and often underreported. In one study of people taking SSRIs for depression, 75% reported some form of sexual dysfunction, including reduced desire, difficulty with arousal, or trouble reaching orgasm. These effects can persist for as long as you’re on the medication, and they’re one of the most common reasons people want to switch or stop.
Less common but notable side effects include sweating, dizziness, yawning, and difficulty concentrating. Weight gain affects a significant portion of users over time and may not appear immediately.
Important Safety Considerations
All antidepressants, including Lexapro, carry an FDA warning about an increased risk of suicidal thoughts and behavior in children, adolescents, and young adults under 25, particularly during the first few months of treatment or when the dose changes. This doesn’t mean the medication causes suicidal behavior in most people. It means that close monitoring matters during the early phase, especially for younger patients. Family members and caregivers should watch for sudden mood shifts, increased agitation, or unusual behavior changes.
Stopping Lexapro abruptly can cause withdrawal-like symptoms, sometimes called discontinuation syndrome. These can include dizziness, irritability, nausea, “brain zaps” (brief electrical-sensation feelings in the head), and flu-like symptoms. Tapering off gradually under medical guidance reduces the risk significantly.
Lexapro should not be taken alongside a class of drugs called MAOIs, and there are interactions with certain migraine medications, blood thinners, and other drugs that affect serotonin. Too much serotonin activity at once can cause a rare but serious condition called serotonin syndrome, which involves agitation, rapid heart rate, high body temperature, and in severe cases, seizures.
How Lexapro Compares to Other SSRIs
Lexapro is the refined version of an older drug called Celexa (citalopram). Celexa contains two mirror-image molecules, but only one of them is therapeutically active. Lexapro contains just the active one, which is why it works at lower doses and tends to cause fewer side effects for some people.
Compared to other SSRIs like sertraline (Zoloft) or fluoxetine (Prozac), Lexapro is often considered a first-line choice because of its tolerability and relatively straightforward dosing. It has fewer drug interactions than some alternatives. That said, individual responses to antidepressants vary widely. A medication that works well for one person may not work for another, and finding the right fit sometimes takes trial and adjustment.