डोफेटिलाइड और ट्राइमेथोप्रिम का इंटरैक्शन

The concomitant use of verapamil or the cation transport system inhibitors cimetidine, trimethoprim (alone or in combination with sulfamethoxazole), or ketoconazole with dofetilide is contraindicated (see WARNINGS and PRECAUTIONS, Drug-Drug Interactions ), as each of these drugs cause a substantial increase in dofetilide plasma concentrations.

The magnitude of the effect on renal elimination by cimetidine, trimethoprim, and ketoconazole (all contraindicated concomitant uses with dofetilide) suggests that all renal cation transport inhibitors should be contraindicated.

Trimethoprim Alone or in Combination with Sulfamethoxazole: (see WARNINGS, CONTRAINDICATIONS ) Concomitant use of trimethoprim alone or in combination with sulfamethoxazole is contraindicated.

Trimethoprim 160 mg in combination with 800 mg sulfamethoxazole co-administered BID with dofetilide (500 mcg BID) for 4 days has been shown to increase dofetilide AUC by 103% and C max by 93%.

…over-the-counter, prescription, and herbal/natural preparations with emphasis on preparations that may affect the pharmacokinetics of dofetilide such as cimetidine (see CONTRAINDICATIONS ), trimethoprim alone or in combination with sulfamethoxazole (see WARNINGS, CONTRAINDICATIONS ), prochlorperazine (see WARNINGS, CONTRAINDICATIONS ), megestrol (see WARNINGS, CONTRAINDICATIONS…