Ketoconazole is a type of prescription medication used to treat fungal infections. Doctors prescribe ketoconazole shampoo for the treatment of conditions that affect your scalp.
Ketoconazole shampoo functions by preventing fungal cells from producing a substance known as ergosterol, which is necessary for the fungus to survive.
Ketoconazole is successful in eliminating a bacterial condition known as sun fungus, which is caused by the fungi tinea versicolor and pityriasis versicolor. Doctors also prescribe the shampoo to eliminate Pityrosporum ovale, a type of yeast that causes dandruff.
In many cases, only one application of ketoconazole shampoo is necessary, reports Drugs.com. When using ketoconazole shampoo, the Mayo Clinic recommends that you leave the solution in place for 5 minutes after lathering before rinsing your hair.
Possible side effects of ketoconazole shampoo include hair oiliness, headaches, changes in hair texture and scalp dryness, itching, stinging, burning or redness. Rarely, ketoconazole shampoo causes hair loss, cautions the Mayo Clinic.
Because the oral version of the medication is known to cause fetal abnormalities, doctors rarely prescribe ketoconazole shampoo for pregnant or nursing mothers. Ketoconazole shampoo is not typically prescribed for children under the age of 12, reports the Mayo Clinic.