Sertraline (brand name Zoloft) and citalopram (brand name Celexa) are both selective serotonin reuptake inhibitors (SSRIs), a class of antidepressants, and the main differences between them are their FDA-approved uses, a heart-rhythm dose limit that applies to citalopram, and how each interacts with other medications. Neither is better for everyone, and research suggests their overall effectiveness for depression is broadly similar. If you take one of them and wonder how it compares, or you’re running low and need a refill, here’s what to know.
Key takeaways
- Sertraline is FDA approved for depression and several anxiety-related conditions, while citalopram is FDA approved for depression in adults, and both usually take several weeks to reach full effect.
- Citalopram has an FDA dose ceiling because higher doses can affect heart rhythm, and switching between the two is a prescribing decision that should be made with your provider.
- If you’re stable on either medication and can’t reach your regular provider before you run out, a physician can review an online refill request for your current prescription.
What are sertraline and citalopram?
Sertraline and citalopram are prescription antidepressants that work by increasing the amount of serotonin, a chemical messenger involved in mood, available between nerve cells in the brain. Both are widely used, available as generics, and taken once a day. The National Institute of Mental Health (NIMH) describes depression as one of the most common mental disorders in the United States, and antidepressants such as SSRIs are a common treatment for it.
Citalopram is closely related to escitalopram (Lexapro). Escitalopram is the active half of the citalopram molecule (its S-enantiomer), and the FDA notes that citalopram’s antidepressant effect comes from that half. The two drugs behave similarly but are dosed differently. You can read more on our escitalopram refill page.
According to the NIMH, antidepressants often take 4 to 8 weeks to work fully, although some symptoms such as sleep or appetite may improve sooner. That timeline applies to both medications.
Get a refill review if you’re running low
If you’re already stable on either medication and can’t reach your regular provider before you run out, a board-certified physician can review a prescription refill request for your current prescription. Starting or switching an SSRI is a decision for your own provider.
With the basics covered, the differences come down to approved uses, dosing, side effects, and interactions.
What is the difference between sertraline and citalopram?
The biggest practical differences are the conditions each is approved to treat and the heart-rhythm dose limit that applies to citalopram. Their side effects overlap considerably.
FDA-approved uses
According to its FDA prescribing information, sertraline is approved for:
- Major depressive disorder, the clinical term for persistent depression that affects daily functioning.
- Obsessive-compulsive disorder (OCD), including in children and adolescents ages 6 to 17.
- Panic disorder, post-traumatic stress disorder (PTSD), and social anxiety disorder, three anxiety-related conditions.
- Premenstrual dysphoric disorder (PMDD), a severe form of premenstrual mood symptoms.
The citalopram prescribing information lists one approved use: major depressive disorder in adults. Prescribers sometimes use medications for conditions outside their approved list (off-label use) when evidence and clinical judgment support it.
Dosing and the citalopram heart-rhythm limit
Sertraline is typically prescribed across a wider dose range than citalopram. Citalopram carries a specific dose ceiling because it can cause QT prolongation, a change in the heart’s electrical rhythm that, in rare cases, can lead to a dangerous irregular heartbeat.
In a drug safety communication, the FDA stated that citalopram should not be used at doses above 40 mg per day, with a lower maximum of 20 mg per day for people over 60, people with liver impairment, people whose bodies clear the drug more slowly (CYP2C19 poor metabolizers), and people taking cimetidine or certain other medications that slow its breakdown. A 2013 study in The BMJ using health records found a dose-related effect on the QT interval for citalopram. Your prescriber may check an electrocardiogram (ECG) or blood electrolytes if you have heart disease or other risk factors. Sertraline’s prescribing information also advises caution in people with risk factors for QT prolongation, though it does not set a heart-related dose cap the way citalopram’s does.
Side effects
The two medications share most common side effects, which often ease in the first few weeks:
- Digestive effects such as nausea, loose stools, or diarrhea, which are among the most commonly reported effects in sertraline’s prescribing information.
- Sleep changes, including drowsiness or trouble sleeping, plus dry mouth and increased sweating.
- Sexual side effects, such as reduced desire or delayed orgasm, which can persist for some people.
- Headache, dizziness, or restlessness, especially early in treatment or after a dose change.
Less common but serious risks for both include serotonin syndrome, increased bleeding risk (particularly with NSAIDs or blood thinners), low sodium levels (hyponatremia), and triggering mania in people with bipolar disorder. Both prescribing labels carry a boxed warning, the FDA’s strongest warning, about an increased risk of suicidal thoughts and behaviors in children, adolescents, and young adults age 24 and younger. The FDA first required this warning for children and adolescents in 2004.
Drug interactions
Both medications must not be combined with monoamine oxidase inhibitors (MAOIs), another class of antidepressants, or with pimozide. Citalopram also calls for caution with other drugs that affect heart rhythm and a lower dose cap with drugs that slow its breakdown, while sertraline can raise levels of some medications processed by the liver. The MedlinePlus sertraline and MedlinePlus citalopram pages list common interactions, and your pharmacist can check your full medication list.
Is sertraline or citalopram more effective?
For depression, research has not found a clear winner. A 2018 network meta-analysis in The Lancet, which pooled data from hundreds of trials, found that all 21 antidepressants studied, including sertraline and citalopram, were more effective than placebo for adults with major depression. Differences between individual drugs were smaller when placebo-controlled trials were included, and in head-to-head trials, sertraline and citalopram were among the medications people were less likely to stop taking.
In practice, prescribers choose based on factors such as:
- Your symptoms and other diagnoses, since sertraline is approved for several anxiety-related conditions.
- Heart health and age, given citalopram’s QT-related dose limits.
- Your other medications, to reduce interaction risk.
- Past response, including how you or a close relative responded to a specific SSRI.
- Pregnancy or breastfeeding plans, which call for an individual discussion with your provider.
If one medication is working well and side effects are manageable, staying consistent usually matters more than which SSRI you take. Our article on consistent SSRI use in long-term anxiety recovery explains why steady dosing matters.
Can you switch between sertraline and citalopram?
Yes, but only with your prescriber’s guidance. Switching is a new prescribing decision rather than a refill, and the approach (a direct switch or a gradual cross-taper) depends on your dose, history, and symptoms.
Stopping either medication suddenly can cause discontinuation symptoms, such as dizziness, irritability, flu-like feelings, trouble sleeping, and brief electric-shock sensations. Don’t stop or switch on your own. If you want to discuss a change, or you’ve noticed new or worsening symptoms, virtual primary care through HealthSource can help you review your options with a physician.
Can I refill sertraline or citalopram online?
If you’re stable on your current dose and have an existing prescription, a physician may be able to review a refill online. Neither sertraline nor citalopram is a controlled substance.
You can see how online refill review works on our sertraline refill page and in our guide to getting a prescription refill without seeing a doctor.
How the process works:
- Complete an online form, which takes about 5 minutes and requires a photo ID, photos of your medication bottles, and a selfie.
- A physician licensed in your state reviews your request, typically within a few hours. You must be physically located in a state where the physician is licensed at the time of your request.
- If approved, the prescription is sent electronically to your chosen pharmacy, usually the same day, for a 30- or 90-day supply. A 12-month refill option is available through a 15-minute video visit.
This service does not refill medications requiring close monitoring, controlled substances, injectable medications, or lifestyle medications, including opioids, benzodiazepines, muscle relaxers, antipsychotics, ADHD medications, weight loss medications, hormone replacement therapy, immunosuppressants including steroids, antibiotics, and antivirals. It also does not diagnose new conditions, start new medications, or switch you from one SSRI to another. Ongoing care with your own provider remains important, and our anxiety medication page explains which treatments may be eligible.
When to seek medical attention
Some symptoms need prompt care rather than a refill. Contact your provider or seek emergency care if you notice:
- Thoughts of suicide or self-harm. Call or text the 988 Suicide & Crisis Lifeline, or call 911 if you’re in immediate danger.
- Signs of serotonin syndrome, such as agitation, confusion, a racing heartbeat, high fever, heavy sweating, or muscle twitching or stiffness. The Mayo Clinic notes severe cases can be life-threatening.
- Fainting, a pounding or irregular heartbeat, or severe dizziness, especially on citalopram.
- Unusual bleeding or bruising, or symptoms of low sodium such as confusion, severe headache, or weakness.
- Worsening depression, or unusually high energy with little need for sleep, which can signal mania.
Frequently asked questions
Is citalopram the same as escitalopram?
They’re closely related but not the same. Escitalopram is the active half of the citalopram molecule, so it’s prescribed at lower doses. The two are not interchangeable without a prescriber adjusting the dose.
Which is better for anxiety, sertraline or citalopram?
Sertraline is FDA approved for panic disorder, PTSD, social anxiety disorder, and OCD, while citalopram’s approved use is depression. Prescribers sometimes use citalopram for anxiety off-label, and the right choice depends on your history.
Can you take sertraline and citalopram together?
They’re generally not combined, because taking two SSRIs raises the risk of serotonin syndrome. Any combination of serotonin-affecting medications should only happen under a prescriber’s direction.
Can you drink alcohol on sertraline or citalopram?
It’s best to ask your prescriber. MedlinePlus notes that alcohol can make the side effects of both sertraline and citalopram worse, and drinking can also worsen depression and add to drowsiness.
Do sertraline and citalopram cause weight gain?
Some people notice weight changes with long-term SSRI use, but responses vary widely. If weight changes concern you, discuss them with your provider rather than stopping the medication.
Refill your current SSRI prescription online
My Med Refills lets a board-certified physician review refill requests for stable, chronic medications such as sertraline, with prescriptions usually sent to your pharmacy the same day after approval. Current pricing is listed on the request page. When you’re ready, you can get a prescription refill.
Sources
- Zoloft (sertraline hydrochloride) Prescribing Information, Viatris Specialty LLC, via DailyMed, National Library of Medicine.
- Celexa (citalopram) Prescribing Information, Allergan, Inc., via DailyMed, National Library of Medicine.
- FDA Drug Safety Communication: Revised Recommendations for Celexa (Citalopram Hydrobromide) Related to a Potential Risk of Abnormal Heart Rhythms With High Doses, U.S. Food and Drug Administration.
- Suicidality in Children and Adolescents Being Treated With Antidepressant Medications, U.S. Food and Drug Administration.
- Cipriani A, et al. Comparative efficacy and acceptability of 21 antidepressant drugs for the acute treatment of adults with major depressive disorder, The Lancet, 2018, via PubMed.
- Castro VM, et al. QT interval and antidepressant use: a cross sectional study of electronic health records, The BMJ, 2013, via PubMed.
- Sertraline, MedlinePlus, National Library of Medicine.
- Citalopram, MedlinePlus, National Library of Medicine.
- Mental Health Medications, National Institute of Mental Health.
- Depression, National Institute of Mental Health.
- Serotonin Syndrome: Symptoms and Causes, Mayo Clinic.
- 988 Suicide & Crisis Lifeline.
This article is for informational purposes only and is not a substitute for professional medical advice.
This is not an emergency service. In an emergency, call 911 or go to the nearest emergency room.