SSRI Head-to-Head · Depression & Anxiety Medications

citalopram

Celexa FDA: MDD only — QTc warning

sertraline

Zoloft FDA: MDD · OCD · PTSD · 3 more

Celexa vs Zoloft: Two SSRIs, Very Different Profiles

Celexa (citalopram) and Zoloft (sertraline) are both selective serotonin reuptake inhibitors used for depression — but Zoloft carries six FDA indications to Celexa's one, and Celexa has an FDA cardiac safety warning at higher strengths that Zoloft does not. Here is a clear comparison of how they differ.

FDA Safety Warning — Celexa only

Celexa (citalopram) carries an FDA warning for QTc interval prolongation at higher strengths, which can rarely lead to serious arrhythmia. The FDA caps the maximum recommended dose at 40 mg/day — and at 20 mg/day for adults over 60, people with liver impairment, and those taking certain CYP2C19 inhibitors. Zoloft carries no comparable cardiac warning.

Same mechanism, different profiles: Both drugs block the serotonin transporter (SERT), increasing synaptic serotonin. The core pharmacology is identical. The meaningful differences are approved indications, cardiac safety, and drug interactions — not how they work in the synapse.

Both: generic available Both: once-daily dosing Both: weight-neutral Celexa: QTc warning Rx only

Side-by-side comparison

Celexa vs Zoloft at a Glance

Scroll horizontally on small screens. Both drugs require a prescription.

Category	Celexa (citalopram)	Zoloft (sertraline)
Generic name	Citalopram hydrobromide	Sertraline hydrochloride
Drug class	SSRI	SSRI
Mechanism	Blocks SERT; racemic mixture (R- and S-enantiomers)	Blocks SERT; single compound
FDA indications	Major depressive disorder (MDD)	Major depressive disorder OCD Panic disorder PTSD Social anxiety disorder PMDD
Indication count	1 (MDD only)	6 (most of any SSRI)
Available strengths	10 mg · 20 mg · 40 mg tablets 10 mg/5 mL oral solution	25 mg · 50 mg · 100 mg tablets 20 mg/mL oral concentrate
Cardiac / QTc	FDA warning Dose-dependent QTc prolongation; max 40 mg/day; 20 mg/day in elderly and certain patients	No QTc concern No FDA QTc warning
Generic available	Yes — inexpensive	Yes — inexpensive
Weight effects	Weight-neutral	Weight-neutral
Half-life	~35 hours	~26 hours
First-line status	Used for MDD; less preferred due to QTc concern and narrow indication range	First-line for depression and multiple anxiety disorders; broadly preferred
CYP interactions	Moderate CYP2C19 substrate; inhibits CYP2D6; CYP2C19 inhibitors raise citalopram levels and increase QTc risk	Moderate CYP2D6 inhibitor; fewer high-stakes interactions

Available strengths

What Strengths Are Available?

Listed strengths are available from generic manufacturers. Neither drug is available in an extended-release formulation. Both are taken once daily.

Celexa (citalopram)

Celexa

citalopram hydrobromide

Tablets

10 mg 20 mg 40 mg

Oral solution

10 mg / 5 mL

Maximum strength limit: The FDA caps Celexa at 40 mg/day due to QTc prolongation risk. Adults over 60, those with hepatic impairment, poor CYP2C19 metabolizers, and patients on CYP2C19 inhibitors are limited to 20 mg/day. The 60 mg strength that existed before 2012 is no longer recommended.

Zoloft (sertraline)

Zoloft

sertraline hydrochloride

Tablets

25 mg 50 mg 100 mg

Oral concentrate

20 mg / mL

No FDA-mandated strength ceiling. The oral concentrate must be diluted before use. Higher strengths up to 200 mg/day are sometimes used for OCD under prescriber supervision, though standard depression doses are typically 50–100 mg.

Drug profiles

About Each Medication

Key differences

Where They Meaningfully Differ

The drugs share a mechanism but diverge in ways that affect prescribing decisions.

FDA indications

1 — major depressive disorder only. No approved anxiety indications. Off-label use for anxiety is common but not FDA-supported.

6 — MDD, OCD, panic disorder, PTSD, social anxiety disorder, and PMDD. The most FDA indications of any SSRI.

Cardiac / QTc

FDA warning: dose-dependent QTc prolongation. Dose capped at 40 mg/day (20 mg in elderly, hepatic impairment, or with CYP2C19 inhibitors). Avoid in patients with congenital long QT syndrome or on other QTc-prolonging drugs.

No FDA QTc warning. Considered safe in patients with cardiovascular disease and in the elderly without the dose restrictions that apply to Celexa.

First-line status

Used for depression but its QTc warning and narrow indication set mean many prescribers reach for alternatives first, especially in older patients or those with co-occurring anxiety.

Broadly considered first-line for depression and the multiple anxiety disorders it covers. Often the default starting point in primary care for both depression and anxiety.

Molecule

Racemic mixture (R- and S-enantiomers). The inactive R-enantiomer contributes to drug interactions and the QTc risk that led to the 2012 FDA warning.

Single compound. Not a racemate. Less interaction with CYP enzymes at standard doses compared to citalopram, though still a moderate CYP2D6 inhibitor at higher doses.

Available strengths

10 mg, 20 mg, 40 mg tablets; 10 mg/5 mL oral solution. The 40 mg tablet is the maximum recommended strength; higher strengths are no longer indicated.

25 mg, 50 mg, 100 mg tablets; 20 mg/mL oral concentrate. Doses up to 200 mg/day are sometimes used for OCD, without a mandated strength ceiling.

Clinical considerations

Who Might Be Prescribed Each

Always based on a full prescriber evaluation. This is a summary of typical clinical reasoning, not individual advice.

Celexa (citalopram)

Adults with depression (MDD) who have tolerated citalopram previously

Patients already stable on citalopram with no reason to switch

Depression without co-occurring anxiety disorders needing FDA-approved coverage

When cost or formulary access makes generic citalopram the practical choice

Zoloft (sertraline)

Depression with co-occurring OCD, panic disorder, PTSD, or social anxiety

Elderly patients where the QTc concern with citalopram is clinically relevant

Patients on other medications that prolong the QTc interval

PMDD without a depressive episode

Patients with cardiovascular conditions where cardiac safety matters

Frequently asked questions

Common Questions

Is Celexa or Zoloft better for depression?

Both Celexa (citalopram) and Zoloft (sertraline) are FDA-approved for major depressive disorder and are considered effective first-line treatments. Head-to-head evidence does not consistently favor one over the other for depression specifically. However, Zoloft is generally preferred by many prescribers as a starting point because it carries no cardiac QTc concern and has a broader safety profile across patient populations, including the elderly. The best choice depends on your complete medical history, other medications, and any co-occurring conditions.

Can Celexa cause heart problems?

In 2012, the FDA issued a safety warning that citalopram (Celexa) can cause dose-dependent QTc interval prolongation, which is an electrical change in the heart that can rarely lead to a dangerous arrhythmia called Torsades de Pointes. As a result, the FDA capped the maximum recommended dose at 40 mg per day, with a lower cap of 20 mg per day for adults over 60, those with liver impairment, and people who take certain CYP2C19 inhibitors. This risk is one reason Zoloft is often favored for elderly patients or those with underlying cardiac conditions. Always discuss your cardiovascular history with your prescriber before starting any SSRI.

Does Zoloft treat anxiety?

Yes. Zoloft (sertraline) has FDA approval for several anxiety-related conditions: panic disorder, post-traumatic stress disorder (PTSD), social anxiety disorder (social phobia), obsessive-compulsive disorder (OCD), and premenstrual dysphoric disorder (PMDD). This breadth makes Zoloft the SSRI with the most FDA indications. Celexa (citalopram), by contrast, is only FDA-approved for major depressive disorder and is not approved for any anxiety disorder, though it is sometimes prescribed off-label for anxiety.

Are Celexa and Zoloft available as generics?

Yes, both are available as low-cost generics. Celexa's generic is citalopram hydrobromide, and Zoloft's generic is sertraline hydrochloride. Both are among the least expensive antidepressants available and are typically covered by most insurance plans and Medicare Part D. Without insurance, generic citalopram and generic sertraline are often available for a few dollars per month at major pharmacy chains and through discount programs.

What are the available strengths of Celexa and Zoloft?

Celexa (citalopram) is available as 10 mg, 20 mg, and 40 mg tablets, and as a 10 mg/5 mL oral solution. Zoloft (sertraline) is available as 25 mg, 50 mg, and 100 mg tablets, and as a 20 mg/mL oral concentrate. Neither is available in an extended-release formulation. Both are taken once daily. Note that due to Celexa's FDA QTc warning, the maximum recommended strength is 40 mg/day (20 mg/day for adults over 60, those with liver impairment, or those taking certain other medications).

Can you switch from Celexa to Zoloft?

Yes, switching from Celexa (citalopram) to Zoloft (sertraline) is a common transition. Because both are SSRIs with similar half-lives (citalopram ~35 hours, sertraline ~26 hours), prescribers typically use a direct switch or a short cross-taper under medical supervision. Abruptly stopping citalopram can cause temporary discontinuation symptoms in some people. Never adjust or stop psychiatric medications without prescriber guidance.

Medical disclaimer

This page is for informational purposes only and does not constitute medical advice, diagnosis, or a treatment recommendation. Drug information can change; always verify with the prescribing information and your healthcare provider. Never start, stop, or change a psychiatric medication without guidance from a licensed prescriber. If you are experiencing a medical emergency, call 911. Poison Control: 1-800-222-1222.