favipiravir

Decreased plasma concentrations of favipiravir, potentially reducing its antiviral efficacy.

Monitor favipiravir efficacy. Consider alternative anticonvulsants if possible. Dose adjustment of favipiravir may be needed, but data are limited.

Increased plasma concentrations of colchicine, leading to increased risk of colchicine toxicity (e.g., gastrointestinal upset, myelosuppression, myopathy).

Avoid concomitant use if possible. If co-administration is necessary, reduce colchicine dose significantly and monitor for signs of toxicity. Consider alternative treatments.

Increased plasma concentrations of digoxin, leading to increased risk of digoxin toxicity (e.g., arrhythmias, nausea, visual disturbances).

Monitor digoxin levels closely and for signs of toxicity. Adjust digoxin dose as needed.

Increased plasma concentrations of dofetilide, leading to increased risk of QT prolongation and Torsades de Pointes.

Avoid concomitant use if possible. If co-administration is necessary, monitor ECG for QT prolongation and dofetilide levels closely. Consider reducing dofetilide dose.

Increased plasma concentrations of fentanyl, leading to increased risk of respiratory depression and sedation.

Monitor for signs of opioid toxicity. Consider reducing fentanyl dose or using an alternative analgesic. Close monitoring is essential.

Increased plasma concentrations of methotrexate, leading to increased risk of methotrexate toxicity (e.g., myelosuppression, mucositis, hepatotoxicity).

Avoid concomitant use if possible. If co-administration is necessary, monitor methotrexate levels and for signs of toxicity closely. Consider reducing methotrexate dose.

Increased plasma concentrations of midazolam, leading to increased sedation and respiratory depression.

Monitor for signs of benzodiazepine toxicity. Consider reducing midazolam dose or using an alternative benzodiazepine not metabolized by CYP3A4. Close monitoring is essential.

Decreased plasma concentrations of favipiravir, potentially reducing its antiviral efficacy. Conversely, favipiravir may inhibit phenytoin metabolism via CYP2C9, leading to increased phenytoin levels.

Monitor favipiravir efficacy and phenytoin levels closely. Adjust phenytoin dose as needed. Consider alternative anticonvulsants if possible.

Increased plasma concentrations of pioglitazone, potentially increasing the risk of adverse effects such as fluid retention and heart failure.

Monitor for signs of pioglitazone toxicity. Consider reducing pioglitazone dose or using an alternative antidiabetic agent.

Increased plasma concentrations of repaglinide, leading to an increased risk of hypoglycemia.

Monitor blood glucose levels closely. Consider reducing repaglinide dose or using an alternative antidiabetic agent.

Decreased plasma concentrations of favipiravir, potentially reducing its antiviral efficacy.

Monitor favipiravir efficacy. Consider alternative anti-tuberculosis drugs if possible. Dose adjustment of favipiravir may be needed, but data are limited.

Increased plasma concentrations of sulfasalazine and its active metabolite, sulfapyridine, potentially leading to increased risk of adverse effects (e.g., gastrointestinal upset, rash, myelosuppression).

Monitor for signs of sulfasalazine toxicity. Consider reducing sulfasalazine dose or using an alternative agent.