Clotrimazole

Common side effects of clotrimazole taken by mouth include nausea and itchiness. When it is applied to the skin, common side effects include redness and a burning sensation. In pregnancy, topical use, even in the vagina, is believed to be safe, nor is there evidence of harm by oral use, but the latter has been less well studied.

Clotrimazole, originally known as BAY b 5097, was discovered in 1969. It is on the World Health Organization's List of Essential Medicines. It is available as a generic medication. In 2023, it was the 259th most commonly prescribed medication in the United States, with more than 1 million prescriptions.

Medical uses

It is available without a prescription in various dosage forms, such as a topical cream, ointment, or vaginal suppository.

An effective treatment option for mixed infectious vaginitis is a combination of clotrimazole and metronidazole.

Topical clotrimazole is usually not effective in the treatment of fungal infections of the scalp or nails; however, when combined with mechanical reduction of the nail, topical clotrimazole cream has been demonstrated to be effective in the treatment of onychomycosis.

Throat lozenge preparations are used for oropharyngeal candidiasis (oral thrush) or prevention of oral thrush in people with neutropenia.

Clotrimazole may be compounded with a glucocorticoid, such as betamethasone, in a topical cream for the treatment of tinea corporis (ringworm), tinea cruris (jock itch), and tinea pedis (athlete's foot). Although temporary relief and partial suppression of symptoms may be observed with the combination therapy, glucocorticoids can elicit an immunosuppressive response and rebound effect that results in more severe infection typically requiring systemic antifungal agents to treat the disease. Combination creams are best avoided to improve treatment outcomes, reduce the possibility of skin atrophy associated with prolonged topical glucocorticoid use, and limit the cost of treatment. It can be effective in treating chronic paronychia. The preferred treatment of tinea infections is therefore clotrimazole monotherapy.

Additionally, clotrimazole may be used to treat the sickling of cells (related to sickle cell anemia).

Pregnancy

Small amounts of clotrimazole may be absorbed systemically following topical and vaginal administration. However, topical clotrimazole is still considered safe to use to treat yeast infections in pregnant women and is a safer alternative to other antifungals.