How long does it take for Lexapro to take effect?

Reviewed by Chimene Richa, MD, 

Written by Linnea Zielinski 

Reviewed by Chimene Richa, MD, 

Written by Linnea Zielinski 

last updated: Apr 19, 2021

6 min read

Collectively, we’re not so good at being patient. We expect two-day delivery, videos on demand, and fast-acting Liqui-Gels. But not all medication works like over-the-counter painkillers that can kick your troublesome headache to the curb in 30 minutes flat. 

Lexapro, a prescription medication used to treat major depressive disorder (MDD) and generalized anxiety disorder (GAD), may take considerably longer to take effect. If you’ve just started taking Lexapro or are discussing the possibility with your healthcare provider, here’s what you need to know about the transition period and what to expect along the way.


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What to expect when you’re started on Lexapro

Finding the right antidepressant for you may be a process. Not everyone responds to every antidepressant medication. Switching to or adding another medication may help, and your healthcare provider will work with you on this as you communicate how you’re feeling with each medication (FDA-a, 2017). 

No matter what your regimen is, it may take several weeks for you to start feeling the effects of any antidepressant medication.

Lexapro (escitalopram) is a type of medication known as a selective serotonin reuptake inhibitor, or SSRI. These medications work by blocking nerve endings from reabsorbing serotonin, leaving more serotonin to transmit messages. Although the exact nature of the connection between serotonin and depression is still up for debate, there’s some evidence to suggest that people with MDD have lower levels of serotonin (Mahar, 2014). However, serotonin isn’t the only component involved; studies have looked at how stress, social, environmental, personality, and other influences may also play a role.

The thought that depression is likely caused by several factors is supported by data about serotonin level changes while taking SSRIs. 

Research suggests that, even though there are increases in serotonin within the first two weeks of treatment with an SSRI, the initial changes don’t necessarily lead to an antidepressant effect—but long-term treatment does. Also, not everyone with a drop in serotonin develops depression and not everyone with depression responds to increased levels of serotonin. Scientists are still trying to understand all of the mechanisms behind depression (Mahar, 2014). 

Since our understanding of conditions like MDD is limited, the exact way medications such as Lexapro work, and why some of them take weeks to work is unclear. Some therapies are able to take effect within one week—but not in everyone to whom they’re prescribed. Researchers don’t quite understand why this is, though there’s great interest in developing medications that are able to work rapidly to reduce depression symptoms (Machado-Vieira, 2010). 

Lexapro is FDA-approved to treat short-term or manage long-term major depressive disorder (MDD) and treat acute generalized anxiety disorder (GAD) (FDA-b, 2017). It may also be prescribed “off-label” to treat obsessive-compulsive disorder (OCD) and binge-eating disorder (BED) (Zutshi, 2007; Guerdjikova, 2007). Off-label means that it’s used in a different way from what is explicitly stated by the FDA. 

Lexapro dosage

Lexapro is available in three different tablet dosages—5 mg, 10 mg, and 20 mg—as well as an oral solution with a concentration of 1 mg/mL. 

This antidepressant may be prescribed to both adults and adolescents to treat major depressive disorder, but is only approved by the FDA to treat generalized anxiety disorder in adults. For the treatment or management of MDD, both adults and adolescents are started on 10 mg daily. For adults, this dose may be increased after the first week, though your healthcare provider may wait longer, depending on your clinical situation. Younger adults need to take their starting dose for at least three weeks before any changes to dosage are made. Both age groups may eventually be raised to a maximum daily dose of 20 mg (FDA-b, 2017).

Certain groups of people are limited to a lower dose of Lexapro, including elderly patients and those with liver or kidney problems. The largest dose these groups may be prescribed is 10 mg per day. Although escitalopram is approved for young adults with major depression, its safety has not been established for anyone younger than 12 years old (FDA-b, 2017). 

No matter what dose you’re prescribed, escitalopram should be stored at room temperature and kept out of the reach of children. This medication can be taken with or without food. In the case of a missed dose, escitalopram should be taken as soon as you remember unless it’s almost time for the next dose. If it’s almost time for your next dose, do not take the missed dose and only take the next dose at the time you normally do (FDA-b, 2017).

Lexapro drug interactions

It’s important to tell your healthcare provider about all the medications and supplements you’re taking, in case of any potential drug interactions. 

One of the most serious risks with escitalopram is serotonin syndrome. This serious, but rare, condition happens when too much serotonin builds up in the body, which can happen due to medications boosting serotonin levels directly or by interfering with how your body breaks down this neurochemical. It may cause mild symptoms such as shivering and mild blood pressure elevation but may also cause seizures, high fevers, coma, and even death (Volpi-Abadie, 2013). 

Escitalopram increases levels of serotonin in the body. For that reason, you should not take it with any drug that does the same thing, including triptans, tricyclic antidepressants, fentanyl, lithium, tramadol, tryptophan, buspirone, amphetamines, and even over-the-counter supplements containing St. John’s Wort (FDA, 2017). 

You should also avoid taking escitalopram at the same time as medications that affect how your body metabolizes serotonin, especially monoamine oxidase inhibitors (MAOIs) such as rasagiline and tranylcypromine. Combining these medications increases your risk of serotonin syndrome (Volpi-Abadie, 2013).

Combining Lexapro with any medication that has a blood-thinning effect can put you at an increased risk of bleeding. This includes prescription blood thinners such as warfarin to over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin, ibuprofen, and naproxen (FDA-b, 2017).

As mentioned, it can take time for escitalopram to work—and it may take even longer before you figure out exactly how it affects you. 

Lexapro may cause sleepiness, especially if you also experience sleep disturbances as a side effect, and it may impair your ability to make decisions. Alcohol may do the same. Although studies haven’t shown that Lexapro amplifies these effects of alcohol, it’s still standard medical advice to avoid drinking if you’re on this medication (FDA-b, 2017).

Lexapro side effects

These common side effects of Lexapro appear to be dose-dependent, meaning there’s a higher chance of experiencing these side effects if you’re on 20 mg than 10 mg. Overall, the most common side effects include (FDA-b, 2017): 

  • Nausea

  • Trouble sleeping (insomnia)

  • Ejaculation disorder

  • Sleepiness

  • Increase in sweating

  • Fatigue/tiredness

  • Low sex drive 

  • Inability to orgasm

Sexual dysfunction is a common side effect of all SSRI antidepressant medications (Jing, 2016). With Lexapro specifically, sexual side effects happened in both sexes in clinical trials. The side effects for men included ejaculation disorder, lowered sex drive, impotence, and priapism, a painful and persistent erection. Women also experienced lower sex drive (FDA-b, 2017). 

If you experience sexual side effects of escitalopram, discuss these changes with your healthcare provider. In some cases, bupropion, mirtazapine, vilazodone, vortioxetine, or serotonin-norepinephrine reuptake inhibitors (SNRIs) may be good alternative treatments. But in patients who only respond to SSRIs, additional treatment with bupropion may help mitigate these side effects (Jing, 2016).

Lexapro withdrawal

If you want to stop taking escitalopram, it’s important to work with a healthcare provider to slowly transition off the medication. If you stop taking it suddenly, you may experience Lexapro withdrawal symptoms such as irritability, agitation, dizziness, anxiety, confusion, headache, lethargy, and insomnia. In some people, an initial lowering of the dose may also cause these side effects. If that’s the case, your healthcare provider may temporarily raise the dose back to where it was in order to restart a slower transition off of the medication (FDA-b, 2017).

When to get medical attention

Serotonin syndrome and Lexapro withdrawal aren’t the only potential serious side effects, though. You should watch closely for any changes in behavior or mental health, including worsening depression, panic attacks, and suicidal thoughts or attempts when first using Lexapro or after a change in dose. Adolescents are at an increased risk of these side effects when taking antidepressant medications (FDA, 2018). If you or someone in your family experiences similar symptoms, get medical help right away.

You should also contact a healthcare professional for medical attention right away if you experience (FDA, 2017):

  • Any symptoms of serotonin syndrome, including coordination problems, hallucinations, racing heart rate, sweating, nausea, vomiting, muscle rigidity, or high or low blood pressure

  • Any symptoms of an allergic reaction, including swelling of the face, lips, or tongue, trouble breathing, rash, or hives

  • Seizures

  • Abnormal bleeding

  • Manic episodes that may include racing thoughts, increased energy, reckless behavior, and talking more or faster than usual

  • Appetite or weight changes, especially in children and adolescents

  • Visual problems, including eye pain and swelling or redness around the eyes

There is help for your depression and/or anxiety

Lexapro is an effective medication for depression and anxiety, but it doesn’t work well for everyone. If it’s not right for you, be sure to speak with your healthcare provider. There are many other options available. 


If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

How we reviewed this article

Every article on Health Guide goes through rigorous fact-checking by our team of medical reviewers. Our reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the writer.

Current version

April 19, 2021

Written by

Linnea Zielinski

Fact checked by

Chimene Richa, MD

About the medical reviewer

Dr. Richa is a board-certified Ophthalmologist and medical writer for Ro.