Fulvicin-U/F, Grifulvin V, Grisactin, Grisovin-FP 
Fulvicin P/G, Grisactin Ultra, Gris-PEG
Classifications: antiinfective; antibiotic; antifungal
Pregnancy Category: C


Griseofulvin Micro-Size 250 mg, 500 mg tablets, 250 mg capsules; 125 mg/5 ml Suspension

Griseofulvin Ultramicrosize 125 mg, 165 mg, 250 mg, 330 mg tablets.


Fungistatic antibiotic derived from species of Penicillium. Arrests metaphase of cell division by disrupting mitotic spindle structure in fungal cells. Deposits in keratin precursor cells and has special affinity for diseased tissue. It is tightly bound to new keratin of skin, hair, and nails, which becomes highly resistant to fungal invasion. Theoretically cross sensitivity with penicillin is a possibility.

Therapeutic Effects

Effective against various species of Epider-mophyton, Microsporum, and Trichophyton (has no effect on other fungi, including Candida, bacteria, and yeasts).


Mycotic disease of skin, hair, and nails not amenable to conventional topical measures. Concomitant use of appropriate topical agent may be required, particularly for tinea pedis.

Unlabeled Uses

Raynaud's disease, angina pectoris, and gout.


Porphyria; hepatic disease; SLE. Safe use during pregnancy (category C), lactation, children 2 y, or for prophylaxis against fungal infections is not established.

Cautious Use

Penicillin-sensitive patients (possibility of cross-sensitivity with penicillin exists; however, reportedly penicillin-sensitive patients have been treated without difficulty).

Route & Dosage

Tinea Corporis, Tinea Cruris, Tinea Capitis
Adult: PO 500 mg micro-size or 330–375 mg ultramicrosize daily in single or divided doses
Child: PO 10–20 mg/kg/d micro-size or 5–10 mg/kg/d ultramicrosize in single or divided doses

Tinea Pedis, Tinea Unguium
Adult: PO 0.75–1 g micro-size or 660–750 mg ultramicrosize daily in single or divided doses (decrease micro-size dose to 500 mg/d after response is noted)
Child: PO 10–20 mg/kg/d micro-size or 5–10 mg/kg/d ultramicrosize in single or divided doses



Adverse Effects (1%)

Body as a Whole: Hypersensitivity (urticaria, photosensitivity, skin rashes, pruritus, fixed drug eruption, serum sickness syndromes, severe angioedema). CNS: Severe headache, insomnia, fatigue, mental confusion, impaired performance of routine functions, psychotic symptoms, vertigo. GI: Heartburn, nausea, vomiting, diarrhea, flatulence, dry mouth, thirst, decreased taste acuity, anorexia, unpleasant taste, furred tongue, oral thrush. Hematologic: Leukopenia, neutropenia, granulocytopenia, punctate basophilia, monocytosis. Urogenital: Nephrotoxicity (proteinuria); hepatotoxicity; estrogen-like effects (in children); aggravation of SLE. Other: Overgrowth of nonsusceptible organisms; candidal intertrigo.


Drug: Alcohol may cause flushing and tachycardia; barbiturates may decrease activity of griseofulvin; may decrease hypoprothrombinemic effects of oral anticoagulants; may increase estrogen metabolism, resulting in break through bleeding, and decrease contraceptive efficacy of oral contraceptives.


Absorption: Absorbed primarily from duodenum; micro-size is variably and unpredictably absorbed; ultramicrosize is almost completely absorbed. Peak: 4–8 h. Distribution: Concentrates in skin, hair, nails, fat, and skeletal muscle; crosses placenta. Metabolism: Metabolized in liver. Elimination: Excreted mainly in urine; some excretion in perspiration. Half-Life: 9–24 h.

Nursing Implications

Assessment & Drug Effects

Patient & Family Education

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug