What It Is
Ketoconazole belongs to a class of medicines called azole antifungals. It is available as a cream, a medicated shampoo, and as tablets.
What It's Used For
Ketoconazole is generally used to treat fungal infections of the skin, such as ringworm and athlete's foot, and conditions caused by yeast such as dandruff and seborrhoeic dermatitis. The shampoo is widely used for dandruff. Tablets are reserved for serious fungal infections when other treatments cannot be used.
How It Works
Ketoconazole blocks an enzyme that fungi need to make ergosterol, a key part of their cell membrane. Without a healthy membrane, the fungus cannot grow or survive. At higher doses, it also reduces the body's production of steroid hormones, which is why it is occasionally used in hormone-related conditions under specialist care.
History and Regulatory Status
Ketoconazole was discovered in the 1970s and was the first azole antifungal that could be taken by mouth. Because tablets can cause liver damage, regulators in several countries have restricted their use. Creams and shampoos have much lower risk, and are widely available, in some countries without a prescription.