Avanafil and Nirmatrelvir and ritonavir interaction

Avanafil and Nirmatrelvir 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.

Major

Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.

What the FDA labels say

From the Avanafil label · effective 2025-12-17

Major

Do not use avanafil in patients taking ritonavir.

Drug interactionsnames Nirmatrelvir and ritonavirView label on DailyMed
Major

Do not use avanafil in patients taking strong CYP3A4 inhibitors [see Warnings and Precautions ( 5.2 ) and Dosage and Administration ( 2.3 )].

Drug interactionsby drug classView label on DailyMed
Moderate

Inhibitors of CYP3A4 may reduce avanafil clearance and increase plasma concentrations of avanafil.

Warnings and precautionsby drug classView label on DailyMed
Moderate

For patients taking concomitant moderate CYP3A4 inhibitors (including erythromycin, amprenavir, aprepitant, diltiazem, fluconazole, fosamprenavir, and verapamil), the maximum recommended dose of avanafil is 50 mg, not to exceed once every 24 hours [see Drug Interactions ( 7.2 )].

Warnings and precautionsby drug classView label on DailyMed
Moderate

CYP3A4 inhibitors (e.g., ketoconazole, ritonavir, erythromycin) increase avanafil exposure ( 7.2 )

Drug interactionsby drug classView label on DailyMed

From the Nirmatrelvir and ritonavir (Paxlovid) label · effective 2026-02-19

Major

…ubrogepant • Mineralocorticoid receptor antagonists: finerenone • Non-opioid analgesic (selective blocker of Na v 1.8 sodium channels): suzetrigine • Opioid antagonists: naloxegol • PDE5 inhibitor: sildenafil (Revatio ® ) when used for pulmonary arterial hypertension (PAH) • Sedative/hypnotics: triazolam, oral midazolam • Serotonin receptor 1A agonist/serotonin…

Contraindicationsby drug classView label on DailyMed
Major

Pulmonary hypertension agents (PDE5 inhibitors) sildenafil (Revatio ® ) ↑ sildenafil Co-administration of sildenafil with PAXLOVID is contraindicated for use in pulmonary hypertension due to the potential for sildenafil associated adverse events, including visual abnormalities hypotension, prolonged erection, and syncope [see Contraindications (4) ] .

Drug interactionsby drug classView label on DailyMed
Major

Pulmonary hypertension agents (PDE5 inhibitors) tadalafil (Adcirca ® ) ↑ tadalafil Avoid concomitant use of tadalafil with PAXLOVID for pulmonary hypertension.

Drug interactionsby drug classView label on DailyMed
Major

Erectile dysfunction agents (PDE5 inhibitors) avanafil ↑ avanafil Do not use PAXLOVID with avanafil because a safe and effective avanafil dosage regimen has not been established. sildenafil, tadalafil, vardenafil ↑ sildenafil ↑ tadalafil ↑ vardenafil Dosage adjustment is recommended for use of sildenafil, tadalafil or vardenafil with PAXLOVID when used for erectile…

Drug interactionsby drug classView label on DailyMed

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Not 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.