Lexapro Versus Celexa: What's the Difference?
Lexapro is the active half of the Celexa molecule. They work much alike, but Celexa lengthens the QTc interval more and has stricter dose limits.
By withClaro Editorial · Medically reviewed by Dr. Jason Tan , Consultant Psychiatrist · 2026-11-09 · 10 min read
Key takeaways Lexapro (escitalopram) is the active half of Celexa (citalopram). 10 mg of Lexapro does roughly the work of 20 mg of Celexa. Head-to-head trials have not shown a clinically meaningful difference in how well the two treat depression. Celexa lengthens the QTc interval more, and its label caps the dose at 20 mg over age 60 and with some medications. Only Lexapro is FDA-approved for generalized anxiety disorder. The choice usually rests on your age, heart health, other medications and past response, not on which drug is stronger. On this page
What is the difference between Lexapro and citalopram? What did a pharmacist get right about Lexapro versus Celexa? Is Lexapro better than Celexa? Which is safer for your heart, Celexa or Lexapro? Which has fewer side effects, Lexapro or Celexa? Is Lexapro better than citalopram for anxiety? Can you switch from Celexa to Lexapro? What should you tell your prescriber when choosing between Celexa and Lexapro? Lexapro versus Celexa comes down to one molecule and its mirror image. Lexapro (escitalopram) holds only the form that does the work. Celexa (citalopram) holds both forms, so the two act in much the same way. Celexa has a stronger effect on the heart's electrical cycle, which is why its dose has stricter limits.
Clinical pharmacist Eric Christianson, PharmD, went through both drugs in a May 2026 episode of the Real Life Pharmacology podcast. The show is made for students and health professionals preparing for exams. We checked each of his claims about Celexa and Lexapro against the FDA labels and the trials.
What is the difference between Lexapro and citalopram?
Lexapro contains only the S-form of the citalopram molecule, the form that does the work. The Lexapro label says it is at least 100 times more potent than the R-form at blocking serotonin reuptake. Celexa contains both forms in equal parts. So a smaller dose of Lexapro does the job of a larger dose of Celexa.
Christianson described Lexapro in plain terms:
It's what's called the S-enantiomer of citalopram. It's generally pretty well tolerated.
The FDA approvals differ too. The Celexa label covers major depression in adults. Lexapro is approved for major depression from age 12 and for generalized anxiety disorder from age 7. The Therapeutics Initiative is a drug review group at the University of British Columbia. It puts 10 mg of escitalopram roughly level with 20 mg of citalopram.
What differs Lexapro (escitalopram) Celexa (citalopram) What it is The S-form of citalopram only S-form and R-form in equal parts FDA-approved for Depression from age 12, generalized anxiety from age 7 Depression in adults Highest usual dose 20 mg a day 40 mg a day Older adults 10 mg a day recommended for most No more than 20 mg a day over age 60 Half-life 27 to 32 hours About 35 hours QTc change in label studies 4.5 ms at 10 mg, 10.7 ms at 30 mg 8.5 ms at 20 mg, 18.5 ms at 60 mg
The generic names are easy to mix up. Before your next appointment, check whether your pharmacy label says escitalopram or citalopram.
What did a pharmacist get right about Lexapro versus Celexa?
Christianson made eight checkable claims about the pair, and seven hold up against the FDA labels and published studies. The one that holds only in part is that Lexapro is easier on the heart. It does change heart rhythm less, but trials have not shown fewer heart problems on it. His ninth point comes from his own practice.
What Christianson said What the research found Does it hold up? Lexapro is the S-enantiomer of citalopram and is generally well tolerated The Lexapro label describes it as the pure S-form of citalopram. A 2018 review of 21 antidepressants put it among the better tolerated Yes Celexa is best known for QTc prolongation, and the risk rises with dose In label studies, QTc rose 8.5 ms at 20 mg and 18.5 ms at 60 mg. Health records of 38,397 adults also showed a dose link Yes In older adults and CYP2C19 poor metabolizers, Celexa should stay at 20 mg The Celexa label sets 20 mg as the maximum over age 60, in poor metabolizers and with liver problems Yes, and the label adds liver problems With omeprazole, the Celexa dose should not be pushed up The label caps Celexa at 20 mg with CYP2C19 inhibitors and names omeprazole and cimetidine among them Yes Lexapro may be a little easier than Celexa on QTc QTc rose 4.5 ms at 10 mg of Lexapro. No head-to-head trial showed fewer QT problems on it Partly: a smaller QTc change, no shown gap in heart problems Both have the usual SSRI side effects, such as sexual problems and stomach upset Side effect rates were similar in head-to-head trials. A 2018 review of 21 antidepressants put both among the better tolerated Yes, with no clear difference between them Celexa has a mid-long half-life of about 30 to 40 hours About 35 hours for Celexa and 27 to 32 hours for Lexapro Yes Sertraline is often preferred with heart disease or QTc risk A 2014 review of six SSRIs found sertraline changed QTc less than citalopram. In a 2002 trial of 369 heart patients, sertraline did not lengthen QTc more than placebo Yes, as common practice After sertraline, the next SSRI he usually sees chosen is escitalopram We found no data on what comes after sertraline. In Medicare and Medicaid, escitalopram use rose in 2015 to 2020 His own practice, with a real trend behind it
Most of these limits come straight from the FDA labels. Ask your pharmacist to check your other medications against the label of the drug you take.
Is Lexapro better than Celexa?
Possibly by a little, but the evidence is split. Meta-analyses that pool many trials tend to favor Lexapro by a small margin. Reviews that look closely at trial quality, or compare the two through placebo trials, find no difference that matters to patients. Neither drug is the clear winner for every patient.
On Lexapro's side is a 2011 meta-analysis of nine studies with 2,009 people. It was led by researchers with ties to the maker. Lexapro came out ahead by 1.7 points on a 60-point depression scale, and remission was 17.6 percentage points more common. A 2009 Cochrane review also found escitalopram ahead of citalopram on response and remission. That review flags a risk that industry funding tilted the results. A 2012 Cochrane review of citalopram reached the same conclusion from the other side.
The case against comes from two angles. A 2012 BMC Medicine analysis found the two equal when compared through 22 placebo-controlled trials. Seven direct trials with 2,174 people did favor escitalopram, so the authors called the advantage unclear. The Therapeutics Initiative reviewed 17 head-to-head trials in 2025, 16 of them in depression with 3,774 adults. Every one had a high risk of bias, and none found a difference big enough to matter clinically.
In a 2018 Lancet review of 21 antidepressants, escitalopram was in the more effective group and citalopram was not. That ranking pools many trials of many drugs, so it is a weaker guide to this pair than the direct trials.
No antidepressant is the strongest for everyone, and the right one is often found by trying.
In large comparisons most antidepressants work similarly on average, with only modest differences between them. They differ more in side effects, interactions and how hard they are to stop. Needing a second choice does not mean the first was a mistake.
Prescribers look at your main symptoms, other conditions, other medications and past response, yours or a close relative's. Some antidepressants are more activating and others more sedating, which can be matched to problems with sleep or energy.
Medical review Medically reviewed by Dr. Jason Tan, Consultant Psychiatrist, on 27 October 2026, this section only. Next review: 27 October 2027.
Between Celexa and Lexapro, the difference that shows up most clearly in the data is the heart, not mood. Write down how you did on any SSRI before, since past response is part of what your prescriber weighs.
Which is safer for your heart, Celexa or Lexapro?
Lexapro lengthens the QTc interval less at usual doses, and only the Celexa label limits the dose for this reason. The QTc interval is the time the heart's lower chambers take to reset electrically between beats. Both drugs can lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
Christianson's main point about Celexa was the heart. He put it this way:
the most notable one that you're going to be tested on is QTc prolongation. So the higher the dose of this medication, the more and more likely that we're going to cause this potential issue.
In the Celexa label study, QTc rose 8.5 ms at 20 mg and 18.5 ms at 60 mg against placebo. The label advises no more than 40 mg a day. The maximum is 20 mg over age 60 and with liver problems. The same applies to CYP2C19 poor metabolizers and with CYP2C19 inhibitors such as omeprazole. Christianson summed up the age limit:
So in elderly patients, we generally don't want to go above 20 milligrams per day.
The label also says to avoid Celexa with an inborn long QT, slow pulse or low potassium or magnesium. The same goes for a recent heart attack or uncompensated heart failure. The Lexapro label puts QTc at 4.5 ms at 10 mg and predicts 6.6 ms at 20 mg. It sets no dose cap for QT. The 2013 BMJ study of health records found QTc rose with dose on escitalopram too.
The Therapeutics Initiative cites a 2012 FDA review: at matched doses, citalopram adds about 4 to 6 ms more. The FDA did not call that gap significant at recommended doses. A 2013 study of US veterans compared citalopram doses in 618,450 people, with 365,898 people on sertraline as a reference group. Citalopram doses above 40 mg did not come with more ventricular arrhythmias or deaths. The FDA label still sets the 40 mg and 20 mg limits, and only your prescriber should change your dose.
For people with heart disease, he named the usual alternative:
Sertraline maybe tends to be preferred in those with cardiovascular disease or patients at risk for QTc prolongation.
The Celexa label advises contacting a healthcare provider right away if you feel faint, lose consciousness or have heart palpitations.
Which has fewer side effects, Lexapro or Celexa?
Neither clearly has fewer. In head-to-head trials, side effects came up at similar rates on both drugs. The labels list the same kinds of problems: nausea, sleep changes and sexual side effects. Those label figures come from separate trials against placebo, so they don't compare the two drugs directly.
Sexual side effects are common on both, in women and men. The Lexapro medication guide lists lower sex drive and delayed or absent orgasm in women. In the depression trials, delayed ejaculation affected 6% of men on Celexa against 1% on placebo. On Lexapro it was 9% against under 1%.
The Celexa label puts nausea at 21% against 14% on placebo, and sleepiness at 18% against 10%. On Lexapro, nausea affected 15% against 7%, and insomnia 9% against 4%. In Celexa's trials, people lost about half a kilogram on average, with no change on placebo.
Note which side effects bother you most and when each one started. For the full picture on one of the two, see the full list of Lexapro side effects .
Is Lexapro better than citalopram for anxiety?
Lexapro has FDA approval for generalized anxiety disorder, and Celexa does not. Prescribers still use Celexa for anxiety off label, meaning outside the uses the FDA approved. No trial has shown which works better for anxiety. They have rarely been tested against each other for it.
Of the 17 head-to-head trials in the 2025 Therapeutics Initiative review, 16 were in depression. The one in panic disorder, from 2003, compared each drug with placebo rather than with each other.
If anxiety is your main reason for treatment, say so at the start, since it can shape the choice. For how the older drug is used here, see how Celexa is used for anxiety .
Can you switch from Celexa to Lexapro?
Yes. Prescribers do move people between these two, and the plan, timing and dose are theirs to set. Some people ask about a switch because of a side effect rather than because the drug stopped helping. Mood may be better while a side effect gets in the way. A trade-off like that is worth raising with your prescriber rather than living with.
Write down when each symptom started and how it changed. For what a change of medication involves in general, see how switching antidepressants works .
What should you tell your prescriber when choosing between Celexa and Lexapro?
Bring the facts that decide the choice, not a wish for the stronger drug. Age, heart health and your other medications set the safe dose range for Celexa. Your main symptoms and past experience shape the rest. A short list makes the appointment quicker and the choice better informed.
It helps to tell them:
Your age, especially if you're over 60. Any heart condition, including long QT syndrome, a slow heart rate or a recent heart attack. Any fainting, dizziness or racing heartbeat, and results of any past ECG. Liver problems, or low potassium or magnesium on a past blood test. Every medication you take, including omeprazole or cimetidine for heartburn. Whether anxiety or depression is your main concern. Past SSRIs and how each went, and which side effects you most want to avoid. Both labels carry a boxed warning about suicidal thoughts in children, teens and young adults. If you're having thoughts of harming yourself, contact emergency services or a crisis line straight away. In the US, call or text 988. In the UK, call Samaritans on 116 123. Elsewhere, find a crisis line near you .
Once you start, short daily notes make the next appointment easier. The withClaro app lets you log mood, energy, sleep and appetite each day. It links side effects to your dose and turns the record into a report for your prescriber.
Download on the App Store Choosing between two close medications comes down to how you feel on yours. The withClaro app lets you log mood, energy, sleep and appetite each day, track side effects against your dose and share a report with your prescriber.
Frequently asked questions Can you take Celexa and Lexapro together? Not unless a prescriber has told you to. Lexapro is the active part of Celexa, so taking both doubles up on the same drug. The Celexa label lists other SSRIs among drugs that raise the risk of serotonin syndrome. If you have both at home, ask your pharmacist which one to keep taking.
Does citalopram cause sweating? It can. In Celexa's depression trials, 11% had more sweating against 9% on placebo, a small gap. If sweating disrupts your sleep or your day, note when it happens and mention it at your next appointment.
What should you never mix with Lexapro? The Lexapro label rules out MAO inhibitors, including linezolid, and pimozide. It warns about serotonin syndrome with other serotonergic drugs such as triptans, lithium and St. John's wort. NSAIDs, aspirin and warfarin raise the risk of bleeding. Show your pharmacist every medicine and supplement you take, including ones bought over the counter.
Why do doctors choose citalopram? In head-to-head trials, citalopram worked about as well as escitalopram. Its dose limits matter more for older adults and people on certain medications. Ask your prescriber why they picked yours, so you know what to watch for.
Can citalopram cause diarrhea? Yes, though not often. In Celexa's depression trials, 8% had diarrhea against 5% on placebo. Write down when it started and tell your prescriber.
Related articles
Sources Eric Christianson, Real Life Pharmacology podcast. SSRIs: Test Prep and Practice Pearls Part 1, May 7, 2026 Lexapro (escitalopram) prescribing information and medication guide, Allergan, FDA label revised October 2023 Celexa (citalopram) prescribing information, Allergan, FDA label revised October 2023 Therapeutics Initiative. Therapeutics Letter 159: Escitalopram vs citalopram, November 2025 Cipriani A, et al. Comparative efficacy and acceptability of 21 antidepressant drugs for the acute treatment of adults with major depressive disorder. Lancet, 2018 Castro VM, et al. QT interval and antidepressant use: a cross sectional study of electronic health records. BMJ, 2013 Beach SR, et al. Meta-analysis of selective serotonin reuptake inhibitor-associated QTc prolongation. Journal of Clinical Psychiatry, 2014 Glassman AH, et al. Sertraline treatment of major depression in patients with acute MI or unstable angina. JAMA, 2002 Cavanah LR, et al. Patterns in (es)citalopram prescriptions to Medicaid and Medicare patients in the United States. Frontiers in Psychiatry, 2025 Montgomery S, et al. Efficacy of escitalopram compared to citalopram: a meta-analysis. International Journal of Neuropsychopharmacology, 2011 Cipriani A, et al. Escitalopram versus other antidepressive agents for depression. Cochrane Database of Systematic Reviews, 2009 Cipriani A, et al. Citalopram versus other anti-depressive agents for depression. Cochrane Database of Systematic Reviews, 2012 Alkhafaji AA, et al. Impact of evergreening on patients and health insurance: a meta analysis and reimbursement cost analysis of citalopram/escitalopram antidepressants. BMC Medicine, 2012 Zivin K, et al. Evaluation of the FDA warning against prescribing citalopram at doses exceeding 40 mg. American Journal of Psychiatry, 2013 Claro articles are for self-monitoring and educational purposes only. They are not a medical device, therapist, or diagnostic tool, and do not replace care from your prescribing clinician. If you are in crisis, contact your care team, emergency services, the Samaritans (UK: 116 123), or the Crisis Text Line (US: text HOME to 741741).
