Nirmatrelvir and ritonavir and Pimavanserin interaction
Nirmatrelvir and ritonavir and Pimavanserin: 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 Nirmatrelvir and ritonavir (Paxlovid) label · effective 2026-02-19
Neuropsychiatric agents suvorexant ↑ suvorexant Avoid concomitant use of suvorexant with PAXLOVID. aripiprazole, brexpiprazole, cariprazine, iloperidone, lumateperone, pimavanserin ↑ aripiprazole ↑ brexpiprazole ↑ cariprazine ↑ iloperidone ↑ lumateperone ↑ pimavanserin Dosage adjustment of aripiprazole, brexpiprazole, cariprazine, iloperidone, lumateperone, and…
…Antiarrhythmic: amiodarone, dronedarone, flecainide, propafenone, quinidine • Anti-gout: colchicine (in patients with renal and/or hepatic impairment [see Table 2 , Drug Interactions (7.3)] ) • Antipsychotics: lurasidone, pimozide • Benign prostatic hyperplasia agents: silodosin • Cardiovascular agents: eplerenone, ivabradine • Ergot derivatives: dihydroergotamine, ergotamine,…
Antipsychotics lurasidone, pimozide ↑ lurasidone ↑ pimozide Co-administration contraindicated due to serious and/or life-threatening reactions such as cardiac arrhythmias [see Contraindications (4) ] .
Antipsychotics quetiapine ↑ quetiapine If co-administration is necessary, reduce quetiapine dose and monitor for quetiapine-associated adverse reactions.
From the Pimavanserin (NUPLAZID) label · effective 2026-06-18
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) ].
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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.