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Citalopram and Pimozide Interaction

Drug interaction information between Citalopram and Pimozide.

Citalopram and Pimozide have a documented major interaction in FDA labeling.

FDA drug labeling documents a major-severity interaction between Citalopram and Pimozide. Major interactions are generally avoided, moderate ones may need monitoring or a dose adjustment, and minor ones are usually low-risk. This page shows the documented mechanism and guidance. Label-documented interactions are not a complete safety review, so always confirm your own medications with a pharmacist or doctor. Educational information, not medical advice.

Drug A

Citalopram

Selective Serotonin Reuptake Inhibitor (SSRI)

Drug B

Pimozide

Typical Antipsychotic

How They Interact

Citalopram increases the amount of pimozide in your blood, which can lead to dangerous heart rhythm problems.

What To Do

This combination is not allowed and must be avoided.

FDA Label Information

Pimozide Clinical Impact: Concomitant use of citalopram with pimozide increases plasma concentrations of pimozide, a drug with a narrow therapeutic index, and may increase the risk of QT prolongation and/or ventricular arrhythmias compared to use of citalopram alone [see Clinical Pharmacology (12.2) ]. Intervention: Citalopram is contraindicated in patients taking pimozide [see Contraindications (4) , Warnings and Precautions (5.2) ]. Intervention: Avoid concomitant use of citalopram with drugs that prolong the QT interval (citalopram is contraindicated in patients taking pimozide) [see...

Frequently Asked Questions

Can I take Citalopram and Pimozide together?

This is a major interaction. This combination is not allowed and must be avoided.

How serious is the interaction between Citalopram and Pimozide?

This interaction is classified as "major" severity by the FDA. Major interactions may be life-threatening or cause serious side effects.

Why do Citalopram and Pimozide interact?

Citalopram increases the amount of pimozide in your blood, which can lead to dangerous heart rhythm problems.

Understanding the Citalopram and Pimozide Interaction

FDA-approved prescribing information for these two drugs flags their combination as a major-severity interaction. Citalopram belongs to the Selective Serotonin Reuptake Inhibitor (SSRI) class and Pimozide belongs to the Typical Antipsychotic class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Citalopram increases the amount of pimozide in your blood, which can lead to dangerous heart rhythm problems. Severity tiers matter: major flags generally advise avoidance, moderate flags often require monitoring or dose adjustment, and minor flags may only call for awareness.

Context around a specific patient determines real-world impact. Citalopram has 9 total documented interactions on file in this dataset, and Pimozide has 24. Each additional medication compounds the interaction surface, which is why pharmacists run full-profile checks rather than evaluating one pair at a time. FDA-derived guidance for this pair is: This combination is not allowed and must be avoided. Timing of doses, renal and hepatic function, age, and other concurrent prescriptions all shape whether a labeled interaction matters clinically.

An interaction flag is not a verdict. A large share of labeled interactions are managed routinely in clinical practice, the fix may be as simple as spacing doses or adding a monitoring test. Others require the prescriber to choose a different medication entirely. This page surfaces FDA-sourced labeling and openFDA data for educational purposes only; it is not medical advice and cannot account for your full clinical picture. Never start, stop, or adjust either Citalopram or Pimozide based on a web page, speak with your prescriber or pharmacist before making any change.

Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. Always consult your healthcare provider about drug interactions.