Gris-PEG (generic: griseofulvin) is a prescription medication used to treat skin infections such as jock itch, athlete's foot, and ringworm; and fungal infections of the scalp, fingernails, and toenails. This medication belongs to a group of drugs called antifungals. It works by inhibiting the growth of certain fungi that cause infection.

Gris-PEG comes in tablet form. It is usually taken once daily, but can be taken up to 4 times daily. Although symptoms may get better in a few days Gris-PEG is usually taken for 2 to 4 weeks for skin infections, 4 to 6 weeks for hair and scalp infections, 4 to 8 weeks for foot infections, 3 to 4 months for fingernail infections, and at least 6 months for toenail infections.

Common side effects include flushing, nausea, vomiting, and diarrhea. Gris-PEG may cause dizziness. Do not drive or operate heavy machinery until you know how it affects you.