Griseofulvin is an oral drug that treats fungal infections of the skin, nails and scalp. It works by interfering with fungal mitosis and is produced by fermenting the fungus Penicillium griseofulvum. Learn about Griseofulvin uses, dosage, side effects, food interactions, and more. Get all the details about Griseofulvin from MedicinesFAQ . Find patient medical information for Griseofulvin (Fulvicin P/G, Gris-PEG, and others) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings