Griseofulvin

Ultramicrosize griseofulvin tablets are indicated for the treatment of the following ringworm infections, tinea corporis (ringworm of the body), tinea pedis (athlete's foot), tinea cruris (ringworm of the groin and thigh), tinea barbae (barber's itch), tinea capitis (ringworm of the scalp), and tinea unguium (onychomycosis, ringworm of the nails), when caused by one or more of the following genera of fungi: Trichophyton rubrum, Trichophyton tonsurans, Trichophyton mentagrophytes, Trichophyton interdigitalis, Trichophyton verrucosum, Trichophyton megnini, Trichophyton gallinae, Trichophyton crateriform, Trichophyton sulphureum, Trichophyton schoenleini, Microsporum audouini, Microsporum canis, Microsporum gypseum and Epidermophyton floccosum. NOTE: Prior to therapy, the type of fungi responsible for the infection should be identified.

Accurate diagnosis of infecting organism is essential. Identification should be made either by direct microscopic examination of a mounting of infected tissue in a solution of potassium hydroxide or by culture on an appropriate medium. Medication must be continued until the infecting organism is completely eradicated as indicated by appropriate clinical or laboratory examination. Representative treatment periods are tinea capitis, 4 to 6 weeks, tinea corporis, 2 to 4 weeks, tinea pedis, 4 to 8 weeks, tinea unguium-depending on rate of growth-fingernails, at least 4 months, toenails, at least 6 months. General measures in regard to hygiene should be observed to control sources of infection or reinfection. Concomitant use of appropriate topical agents is usually required, particularly in treatment of tinea pedis.

Two cases of conjoined twins have been reported since 1977 in patients taking griseofulvin during the first trimester of pregnancy. Griseofulvin should not be prescribed to pregnant patients. If the patient becomes pregnant while taking this drug, the patient should be apprised of the potential hazard to the fetus. This drug is contraindicated in patients with porphyria or hepatocellular failure and in individuals with a history of hypersensitivity to griseofulvin.

Prophylactic Usage Safety and efficacy of griseofulvin for prophylaxis of fungal infections have not been established. Serious Skin Reactions Severe skin reactions (e.g., Stevens-Johnson syndrome, toxic epidermal necrolysis) and erythema multiforme have been reported with griseofulvin use. These reactions may be serious and may result in hospitalization or death. If severe skin reactions occur, griseofulvin should be discontinued. Hepatotoxicity Elevations in AST, ALT, bilirubin, and jaundice have been reported with griseofulvin use. Patients should be monitored for hepatic adverse events and discontinuation of griseofulvin considered if warranted. Animal Toxicology Chronic feeding of griseofulvin, at levels ranging from 0.5% to 2.5% of the diet resulted in the development of liver tumors in several strains of mice, particularly in males.

There have been post-marketing reports of severe skin and hepatic adverse events associated with griseofulvin use. When adverse reactions occur, they are most commonly of the hypersensitivity type such as skin rashes, urticaria, erythema multiforme-like drug reactions, and rarely, angioneurotic edema, and may necessitate withdrawal of therapy and appropriate countermeasures. Paresthesia of the hands and feet have been reported after extended therapy. Other side effects reported occasionally are oral thrush, nausea, vomiting, epigastric distress, diarrhea, headache, fatigue, dizziness, insomnia, mental confusion, and impairment of performance of routine activities. Proteinuria and leukopenia have been reported rarely. Administration of the drug should be discontinued if granulocytopenia occurs.

Store at 20° to 25°C (68° to 77°F).