Antifungal Therapy - 3
There are several important drug interactions associated with antifungal medications. Absorption of itraconazole (Sporanox® z) and ketoconazole (Nizoral® z) may be altered by antacids, anticholinergic, antispasmodics, histamine H2 antagonists (Tagamet® i, Zantac® a), Prilosec® aa and, Carafate® bb for stomach ulcers, all of which result in treatment failures. Altered blood glucose levels may occur when antidiabetic agents are taken with fluconazole (Diflucan® b) or Sporanox®. Antifungal agents increase prothombin time, increasing the anticoagulant effect of warfarin (Coumadin® cc). Concomitant use of antifungals, phenytoin and cyclosporine increases phenytoin and cyclosporine toxicity Sporanox® and Nizoral® increase serum digoxin levels, which may lead to toxicity. Sporanox® has been shown to significantly increase levels of HMG-CoA reductase inhibitors (Lipitor® h, Mevacor® c, Pravachol® dd, Zocor® h); these drugs may need to be temporarily stopped if systemic use of an azole antifungal is indicated. Amphotericin B increases the toxicity of cyclosporine, corticosteroids and aminoglycosides. Finally, clients should be cautioned not to use alcohol when using antifungal medications.29,53
Concurrent use of azole antifungals and alcohol may result in liver damage. Concomitant use of alcohol with ketoconazole may result in flushing, vomiting, increased respiratory rate and tachycardia.53
