Cilostazol and Nirmatrelvir and ritonavir interaction
Cilostazol 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.
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
Cardiovascular agents aliskiren, ticagrelor, vorapaxar clopidogrel ↑ aliskiren ↑ ticagrelor ↑ vorapaxar ↓ clopidogrel active metabolite Avoid concomitant use with PAXLOVID. cilostazol ↑ cilostazol Dosage adjustment of cilostazol is recommended.
Refer to the cilostazol prescribing information for more information. mavacamten ↑ mavacamten Co-administration with mavacamten may increase mavacamten plasma concentration and increase the risk of heart failure.
From the Cilostazol label · effective 2026-01-14
Inhibitors of CYP3A4 or CYP2C19 Inhibitors of CYP3A4 Coadministration of strong (e.g., ketoconazole) and moderate (e.g., erythromycin, diltiazem and grapefruit juice) CYP3A4 inhibitors can increase exposure to cilostazol.
Reduce cilostazol dose to 50 mg twice daily when coadministered with strong or moderate inhibitors of CYP3A4 [see Dosage and Administration ( 2.2 ) and Clinical Pharmacology ( 12.3 )].
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.