Major Uses

Griseofulvin is a fungistatic antibiotic used to treat ringworm and other dermatophytic infections. It is most commonly used in dogs and cats to treat dermatophytic fungal infections of the skin, hair, and claws, and for treating ringworm in horses.

Common Precautions

Griseofulvin should not be used in pregnant animals, or in horses intended for food. Kittens may be oversensitive to the drug, so usage should be monitored carefully. Cats should also be tested for FIV before using griseofulvin because of possible neutropenic or panleukopenic effects.

Side effects associated with griseofulvin are anorexia, vomiting, diarrhea, anemia, neutropenia, leukopenia, thrombocytopenia, depression, ataxia, hepatotoxicity, dermatitis/photosensitivity and toxic epidermal necrolysis. However, most side effects are uncommon when typical doses are administered. Cats are more likely to experience side effects because they are slower to metabolize the drug.

Griseofulvin should not be used in animals with a known allergy or hypersensitivity to the drug. A veterinarian should be contacted immediately if any unusual symptoms are displayed after the medication is administered or an overdose is suspected.


Griseofulvin should be kept at room temperature in a tight, light resistant, childproof container. It should be stored where children and pets will not be able to reach it, and where it will not be exposed to temperatures above 104 degrees Fahrenheit.


Griseofulvin is most commonly administered as a micro-size tablet. To treat dermatophytic infections in dogs, a common dose is between 25-50 mg/kg once daily with a fatty meal. For cats, a common dose is between 50-120 mg/kg once daily with a fatty meal. For cats with feline eosinophilic granuloma complex, a common dose is 25 mg/kg twice daily with food. Should a regularly scheduled dose be forgotten, it should be administered as soon as possible. If the next scheduled dose is near, the forgotten dose should be skipped and the regular administration schedule resumed. Two doses should not be given at the same time, as an overdose may occur.

Doses may vary in different species, when the drug is given by a different route or concurrently with other medications, and with regards to a patient's age, breed, and health status. A veterinarian's dosing instructions and/or those printed on the medication label should be followed closely.

This information is for general reference only and should not be used for the diagnosis or treatment of any condition of your pet. It's intended as a general reference, this information may not include all possible uses, precautions, directions, reactions (including allergic), drug interactions, or withdrawal times. Always consult your local veterinarian and have your pet examined for any advice concerning the diagnosis and treatment of your pet, including which products and doses are most appropriate. Any trademarks are the property of their respective owners. VetDepot is not a pharmacy. All prescription products are dispensed by our Pharmacy Partner. Article last updated 2/2014.