Antifungal drugs that are applied topically rarely cause side effects unless the patient is allergic to the drug. Side effects are more common when drugs are taken orally or intravenously. The most common reactions from azole drugs are nausea, diarrhea and other gastrointestinal symptoms. These symptoms usually affect less than 10% of patients. Caspofungin also produces few side effects. The most common side effect is a rash.
Amphotericin B can be quite toxic and most patients experience side effects. These include fever, rigors, and chills. Premedication with acetaminophen, diphenhydramine, hydrocortisone, and sometimes meperidine can be given to prevent these side effects. Amphotericin B can also seriously damage the kidneys. However, patients are carefully monitored while taking this drug. If symptoms develop, the liposomal alternative is usually given. Lipid formulations of amphotericin B are far less damaging to the kidneys.
Drug interactions are significant with antifungal treatment. Patients taking amphotericin B should not take any other drug that can cause kidney damage. Potentially serious reactions can occur when patients taking azole antifungal therapies also take certain antihistamines such as astemizole (Hismanal) or the statin drug lovastatin (Mevacor). Patients on antifungal therapy who plan to take other prescribed, over the counter, or alternative medicines should always check with their doctor first.
Alison McTavish, M.Sc.
—A fungal infection that can be life-threatening to patients with a weakened immune system.
—A fungal infection that can be mild or very serious depending on what part of the body it infects.