What Is Celexa (Citalopram) Used For?
Celexa is the brand name for citalopram, an SSRI antidepressant approved in the US for depression.
By withClaro Editorial · 2026-11-02 · 4 min read
Clinical section reviewed by Dr. Jason Tan, Consultant Psychiatrist, on October 27, 2026.
More about Celexa
Key takeaways
- Celexa is the brand name for citalopram, an SSRI approved in the US for depression in adults.
- It starts at 20 mg a day and can go up to 40 mg; doses above 40 mg aren't recommended because of heart rhythm risk.
- People over 60, people with liver problems and people who break citalopram down slowly are limited to 20 mg.
- Celexa is often prescribed for anxiety, which is an off-label use.
Celexa is used for depression in adults. Its generic name is citalopram, and it was first approved in the US in 1998. It is not approved for children or teenagers. It is one of the older, widely used generics: ClinCalc's Top 300 for 2024 puts it at about 12.5 million US prescriptions, for about 2.9 million people.
What is Celexa used for?
In the US it is approved only for major depressive disorder, and only in adults. Prescribers also use it for anxiety and panic, which is off label, meaning outside the approved uses. More in Celexa for anxiety.
Is Celexa an SSRI?
Yes. Citalopram is a selective serotonin reuptake inhibitor: it stops nerve cells from taking serotonin back up after release, so more stays active between them. "Selective" means it does this with little effect on other brain chemicals such as norepinephrine and dopamine, which sets SSRIs apart from many other antidepressants. Other SSRIs include Lexapro, Zoloft and Prozac. For the other types, see the list of antidepressants.
How does Celexa work?
Medically reviewed by Dr. Jason Tan on October 27, 2026, this section only.
After a nerve cell releases serotonin, it normally takes most of it back up. Citalopram slows that uptake, so more serotonin stays in the gap between nerve cells. Why this lifts mood is not fully known, the label says, and MedlinePlus says it may take several weeks before you notice the full benefit. Why there is a gap between the chemical change and the effect is set out in the clinical view:
Antidepressants change how the brain uses chemical messengers, but how this lifts mood is not fully understood.
The chemical change starts within hours, yet the full effect on mood takes weeks. Current thinking points to early changes in how the brain processes emotion, then slower changes in receptors, in brain circuits that handle emotion, and in how the brain forms new connections.
The idea that depression comes from a shortage of serotonin is now considered too simple. That leaves the mechanism unclear, as with many effective medicines. Trials show antidepressants help more than placebo, with the clearest benefit in moderate to severe depression. ## How is Celexa different from Lexapro?
Lexapro (escitalopram) is made from citalopram itself. Citalopram is a mix of two mirror-image forms of the same molecule, and escitalopram is one of them, the S form. So the two are not taken at the same dose; Celexa's maximum is 40 mg because of heart rhythm risk. In a 2018 analysis of 21 antidepressants, escitalopram was among the more effective in head-to-head trials, and citalopram among the better tolerated, though the certainty of the evidence was moderate to very low. Any switch between them is planned with your prescriber.
What doses does Celexa come in?
Celexa tablets come in 10 mg, 20 mg and 40 mg, and the 20 mg and 40 mg tablets are scored to split. The label starts at 20 mg once a day, with or without food, and allows 40 mg after at least a week. Doses above 40 mg aren't recommended because of the risk of heart rhythm changes (QT prolongation). The label's maximum depends on who you are:
| Who | Maximum a day |
|---|
| Most adults | 40 mg |
| Over 60, liver problems, slow CYP2C19 metabolizers, or taking cimetidine or another CYP2C19 blocker | 20 mg | More in Celexa dosage. |
What side effects does Celexa cause?
In the trials, the reaction most clearly linked to citalopram was ejaculation problems in men, 6% against 1% on placebo. Nausea affected 21% against 14%, dry mouth 20% against 14%, sleepiness 18% against 10%, insomnia 15% against 14% and sweating 11% against 9%, so insomnia and sweating were nearly as common on placebo. On weight, a 2024 study of 183,118 people found about 0.12 kg more gain on citalopram than on sertraline over six months, a small difference.
Like every US antidepressant, it carries an FDA boxed warning about suicidal thoughts in people 24 and younger. Watch for new or sudden changes in mood, behavior or thoughts in the first weeks and after each dose change, and call your prescriber right away if they come. 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.
What should you tell your prescriber before starting Celexa?
Some conditions and medications change how Celexa is used, so name them at the first appointment. The label asks prescribers to check for these before starting:
- heart rhythm problems, heart failure or a recent heart attack
- low potassium or magnesium
- liver problems, and your age if over 60
- other antidepressants, antipsychotics, some antibiotics or methadone
- any personal or family history of bipolar disorder or mania, which the label asks prescribers to screen for
- pregnancy, plans for pregnancy or breastfeeding
Two combinations are ruled out. Celexa must not be taken with an MAOI antidepressant, including linezolid or intravenous methylene blue, or within 14 days of stopping one, because of serotonin syndrome risk. It must not be taken with pimozide, because of heart rhythm risk.
Download on the App Store Celexa can change sleep and energy before mood. The withClaro app lets you log mood, sleep, energy and side effects each day, linked to your dose, and turns it into a report for your prescriber.
Related articles
Sources
- CELEXA (citalopram) prescribing information, US Food and Drug Administration via DailyMed
- ClinCalc DrugStats: The Top 300 Drugs of 2024
- MedlinePlus: Citalopram
- Cipriani et al., 2018, The Lancet: Comparative efficacy and acceptability of 21 antidepressant drugs
- Petimar J, et al. Medication-induced weight change across common antidepressant treatments. Annals of Internal Medicine, 2024
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).