An oral antifungal medication.
Information about Ketoconazole
Liver safety of Ketoconazole
Ketoconazole is a well documented cause of clinically apparent acute drug induced liver injury and is no longer recommended as a first line antifungal agent.
Mechanism of action of Ketoconazole
Ketoconazole (kee" toe kon' a zole) is an imidazole derivative and fungicidal agent which is believed to work by several mechanisms, including inhibition of the fungal 14a-ergosterol demethylase which is responsible for converting lanosterol to ergosterol and which blocks fungal cell membrane synthesis. Ketoconazole may also inhibit fungal triglyceride and phospholipid synthesis and fungal oxidative and peroxidative enzyme activity, causing accumulation of hydrogen peroxide, contributing to deterioration of organelles. Ketoconazole has been used in the treatment of many fungal infections including blastomycosis, candidiasis, coccidiomycosis, tinea pityriasis versicolor and histoplasmosis. Ketaconazole has also been used as adjuvant therapy of prostate cancer, because of its effects in lowering androgen production by both the testes and adrenal glands.
FDA approval information for Ketoconazole
Ketoconazole was approved for use in the United States in 1981, but has been replaced by other antifungal agents which have fewer side effects and wider range of activity. Because of its potential for severe adverse reactions including hepatotoxicity, ketoconazole has been withdrawn in many countries and has strict labeling in the United States recommending that it be used only when other effective antifungal agents are not available or tolerated.
Clinical use of Ketoconazole
Current indications include systemic fungal infections due to candida, blastomycosis, coccidiomycosis, histoplasmosis, chromomycosis and paracoccidioidomycosis. Ketoconazole is available as 200 mg tablets in several generic forms and previously under the brand name of Nizoral.
Dosage and administration for Ketoconazole
The recommended dose for fungal infections is 200 to 400 mg once daily by mouth in adults and 3.3 to 6.6 mg/kg in children older than 2 years of age. The dose used for prostate cancer is 400 mg three times daily. Ketoconazole is also available as a cream, solution and shampoo for cutaneous fungal infections.
Side effects of Ketoconazole
Common side effects include pruritus, nausea, rash, abdominal pain, headache, dizziness, fatigue, impotence, menstrual abnormalities and gynecomastia. Severe adverse events include anaphylaxis, hepatotoxicity, endocrine dysregulation and prolongation of the QTc interval.