Pimavanserin and Ritonavir interaction
Pimavanserin and Ritonavir: 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 Pimavanserin (NUPLAZID) label · effective 2026-06-18
Strong or Moderate CYP3A4 Inducers: Avoid concomitant use of NUPLAZID.
Intervention: Avoid concomitant use of strong or moderate CYP3A4 inducers with NUPLAZID [see Dosage and Administration (2.3) ] .
Strong CYP3A4 Inhibitors: Reduce NUPLAZID dose to 10 mg once daily.
Strong CYP3A4 Inhibitors Clinical Impact: Concomitant use of NUPLAZID with a strong CYP3A4 inhibitor increases pimavanserin exposure [see Clinical Pharmacology (12.3) ] .
Intervention: If NUPLAZID is used with a strong CYP3A4 inhibitor, reduce the dosage of NUPLAZID [see Dosage and Administration (2.3) ].
From the Ritonavir (Norvir) label · effective 2026-07-23
…Antagonist: alfuzosin ○ Antianginal: ranolazine ○ Antiarrhythmics: amiodarone, dronedarone, flecainide, propafenone, quinidine ○ Antifungal: voriconazole ○ Anti-gout: colchicine ○ Antipsychotics: lurasidone, pimozide ○ Ergot Derivatives: dihydroergotamine, ergotamine, methylergonovine ○ GI Motility Agent: cisapride ○ HMG-CoA Reductase Inhibitors: lovastatin,…
Antipsychotics: lurasidone pimozide ↑ lurasidone ↑ pimozide Contraindicated due to potential for serious and/or life-threatening reactions [see Contraindications ( 4 ) ] .
Antipsychotics: perphenazine, risperidone, thioridazine ↑ antipsychotics A dose decrease may be needed for these drugs when co-administered with ritonavir.
Antipsychotics: quetiapine ↑ quetiapine Initiation of NORVIR in patients taking quetiapine: Consider alternative antiretroviral therapy to avoid increases in quetiapine exposures.
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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.