Pimozide and Risperidone interaction
Pimozide and Risperidone: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Pimozide label · effective 2026-08-12
Because pimozide prolongs the QT interval of the electrocardiogram it is contraindicated in patients with congenital long QT syndrome, patients with a history of cardiac arrhythmias, patients taking other drugs which prolong the QT interval of the electrocardiogram or patients with known hypokalemia or hypomagnesemia (see also PRECAUTIONS - DRUG INTERACTIONS ).
Hyperpyrexia, not associated with the above symptom complex, has been reported with other antipsychotic drugs.
From the Risperidone (RISPERDAL CONSTA) label · effective 2025-11-05
RISPERDAL CONSTA and other antipsychotic drugs should be used cautiously in patients at risk for aspiration pneumonia. [see also Boxed Warning and Warnings and Precautions (5.1) ] 5.13 Priapism Priapism has been reported during postmarketing surveillance [see Adverse Reactions (6.2) ] .
Risperidone is associated with higher levels of prolactin elevation than other antipsychotic agents.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.