Dofetilide Interactions

Brand names: Dofetilide

8 interactions on record

Hydrochlorothiazide (HCTZ) Alone or in Combination with Triamterene: (see CONTRAINDICATIONS ) Concomitant use of HCTZ alone or in combination with triamterene is contraindicated.

Source: FDA drug label - dofetilide

Ketoconazole: (see WARNINGS, CONTRAINDICATIONS ) Concomitant use of ketoconazole is contraindicated. Ketoconazole at 400 mg daily (the maximum approved prescription dose) co-administered with dofetilide (500 mcg BID) for 7 days has been shown to increase dofetilide C max by 53% in males and 97% in females, and AUC by 41% in males and 69% in females.

Source: FDA drug label - dofetilide

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%.

Source: FDA drug label - dofetilide

Other Drugs: In healthy volunteers, amlodipine, phenytoin, glyburide, ranitidine, omeprazole, hormone replacement therapy (a combination of conjugated estrogens and medroxyprogesterone), antacid (aluminum and magnesium hydroxides), and theophylline did not affect the pharmacokinetics of dofetilide.

Source: FDA drug label - dofetilide

Other Drugs: In healthy volunteers, amlodipine, phenytoin, glyburide, ranitidine, omeprazole, hormone replacement therapy (a combination of conjugated estrogens and medroxyprogesterone), antacid (aluminum and magnesium hydroxides), and theophylline did not affect the pharmacokinetics of dofetilide.

Source: FDA drug label - dofetilide

Inhibitors of this isoenzyme (e.g., macrolide antibiotics, azole antifungal agents, protease inhibitors, serotonin reuptake inhibitors, amiodarone, cannabinoids, diltiazem, grapefruit juice, nefazadone, norfloxacin, quinine, zafirlukast) should be cautiously co-administered with dofetilide as they can potentially increase dofetilide levels.

Source: FDA drug label - dofetilide

If a patient requires dofetilide and anti-ulcer therapy, it is suggested that omeprazole, ranitidine, or antacids (aluminum and magnesium hydroxides) be used as alternatives to cimetidine, as these agents have no effect on the pharmacokinetic profile of dofetilide. Other Drugs: In healthy volunteers, amlodipine, phenytoin, glyburide, ranitidine, omeprazole, hormone replacement therapy (a combination of conjugated estrogens and medroxyprogesterone), antacid (aluminum and magnesium hydroxides), and theophylline did not affect the pharmacokinetics of dofetilide.

Source: FDA drug label - dofetilide

In addition, studies in healthy volunteers have shown that dofetilide does not affect the pharmacokinetics or pharmacodynamics of warfarin, or the pharmacokinetics of propranolol (40 mg twice daily), phenytoin, theophylline, or oral contraceptives.

Source: FDA drug label - dofetilide