Nirmatrelvir and ritonavir and Tadalafil interaction

Nirmatrelvir and ritonavir and Tadalafil: 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 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

From the Tadalafil (Cialis) label · effective 2026-06-03

Moderate

Ritonavir (200 mg twice daily), increased tadalafil 20-mg single-dose exposure (AUC) by 124% with no change in C max , relative to the values for tadalafil 20 mg alone.

Drug interactionsnames Nirmatrelvir and ritonavirView label on DailyMed
Moderate

…Physicians should be aware that CIALIS for once daily use provides continuous plasma tadalafil levels and should consider this when evaluating the potential for interactions with medications (e.g., nitrates, alpha-blockers, anti-hypertensives and potent inhibitors of CYP3A4) and with substantial consumption of alcohol [see Drug Interactions ( 7.1 , 7.2 , 7.3 )] .

Warnings and precautionsby drug classView label on DailyMed
Moderate

The dose of CIALIS for use as needed should be limited to 10 mg no more than once every 72 hours in patients taking potent inhibitors of CYP3A4 such as ritonavir, ketoconazole, and itraconazole [see Drug Interactions ( 7.2 )] .

Warnings and precautionsby drug classView label on DailyMed
Moderate

In patients taking potent inhibitors of CYP3A4 and CIALIS for once daily use, the maximum recommended dose is 2.5 mg [see Dosage and Administration ( 2.7 )] .

Warnings and precautionsby drug classView label on DailyMed
Moderate

CYP3A4 inhibitors (e.g. ketoconazole, ritonavir) increase CIALIS exposure ( 2.7 , 5.10 , 7.2 ) requiring dose adjustment: CIALIS for use as needed: no more than 10 mg every 72 hours CIALIS for once daily use: dose not to exceed 2.5 mg CYP3A4 inducers (e.g. rifampin) decrease CIALIS exposure ( 7.2 ).

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.