No

Antifungal Agent, Oral

Treatment of susceptible tinea infections of the skin, hair, and nails

C

Hypersensitivity to griseofulvin or any component; severe liver disease, porphyria (interferes with porphyrin metabolism)

Safe use in children <2 years of age has not been established; during long-term therapy, periodic assessment of hepatic, renal, and hematopoietic functions should be performed; may cause fetal harm when administered to pregnant women; avoid exposure to intense sunlight to prevent photosensitivity reactions; hypersensitivity cross reaction between penicillins and griseofulvin is possible

>10%: Dermatologic: Rash, urticaria

1% to 10%:

Central nervous system: Headache, fatigue, dizziness, insomnia, mental confusion

Dermatologic: Photosensitivity

Gastrointestinal: Nausea, vomiting, epigastric distress, diarrhea

Miscellaneous: Oral thrush

<1%: Angioneurotic edema, menstrual toxicity, GI bleeding, leukopenia, hepatotoxicity, proteinuria, nephrosis

Symptoms of overdose include lethargy, vertigo, blurred vision, nausea, vomiting, diarrhea

Following GI decontamination, treatment is supportive

Decreased effect:

Barbiturates may decrease levels of griseofulvin

Decreased warfarin, cyclosporine, and salicylate activity with griseofulvin

Griseofulvin decreases oral contraceptive effectiveness

Increased toxicity: With alcohol tachycardia and flushing

Inhibits fungal cell mitosis at metaphase; binds to human keratin making it resistant to fungal invasion

Absorption: Ultramicrosize griseofulvin absorption is almost complete; absorption of microsize griseofulvin is variable (25% to 70% of an oral dose); absorption is enhanced by ingestion of a fatty meal (GI absorption of ultramicrosize is ~1.5 times that of microsize)

Distribution: Crosses the placenta

Metabolism: Extensive in the liver

Half-life: 9-22 hours

Elimination: <1% excreted unchanged in urine; also excreted in feces and perspiration

Oral:

Microsize: 10-20 mg/kg/day in single or 2 divided doses

Ultramicrosize: >2 years: 5-10 mg/kg/day in single or 2 divided doses

Adults:

Microsize: 500-1000 mg/day in single or divided doses

Ultramicrosize: 330-375 mg/day in single or divided doses; doses up to 750 mg/day have been used for infections more difficult to eradicate such as tinea unguium

Duration of therapy depends on the site of infection:

Tinea corporis: 2-4 weeks

Tinea capitis: 4-6 weeks or longer

Tinea pedis: 4-8 weeks

Tinea unguium: 3-6 months or longer

Enhanced absorption with high fat meals; for enhanced absorption, should be administered with high fat meal; alcohol will cause "disulfiram"-type reaction consisting of flushing, headache, nausea, and in some patients, vomiting and chest and/or abdominal pain

Oral: Administer with a fatty meal (peanuts or ice cream to increase absorption), or with food or milk to avoid GI upset

Periodic renal, hepatic, and hematopoietic function tests

False-positive urinary VMA levels

May cause dizziness, confusion, or insomnia

May rarely cause leukopenia; use caution with clozapine and carbamazepine; barbiturates may decrease levels of griseofulvin

No information available to require special precautions

Griseofulvin may cause soreness or irritation of mouth or tongue

Take as directed; around-the-clock with food. Take full course of medication; do not discontinue without notifying prescriber. Avoid alcohol while taking this drug (disulfiram reactions). Practice good hygiene measures to prevent reinfection. Frequent blood tests may be required with prolonged therapy. You may experience nausea and vomiting (small, frequent meals may help); confusion, dizziness, drowsiness (use caution when driving or engaging in tasks that require alertness until response to drug is known); nausea, vomiting, or diarrhea (small frequent meals, frequent mouth care, sucking lozenges, or chewing gum may help); increased sensitivity to sun (use sunscreen, wear protective clothing and eyewear, and avoid excessive exposure to direct sunlight). Report skin rash, respiratory difficulty, CNS changes (confusion, dizziness, acute headache), changes in color of stool or urine, white plaques in mouth, or worsening of condition. Breast-feeding precautions: Inform prescriber if pregnant. Consult prescriber if breast-feeding.

Monitor periodic renal, hepatic, and hematopoietic function tests

Microsize:

Capsule: 125 mg, 250 mg

Suspension, oral (Grifulvin® V): 125 mg/5 mL with alcohol 0.2% (120 mL)

Tablet:

Fulvicin-U/F®, Grifulvin® V: 250 mg

Fulvicin-U/F®, Grifulvin® V, Grisactin-500®: 500 mg

Ultramicrosize:

Tablet:

Fulvicin® P/G: 165 mg, 330 mg

Fulvicin® P/G, Grisactin® Ultra, Gris-PEG®: 125 mg, 250 mg

Grisactin® Ultra: 330 mg

Ginsburg CM, McCracken GH Jr, Petruska M, et al, "Effect of Feeding on Bioavailability of Griseofulvin in Children," J Pediatr, 1983, 102(2):309-11.

Kawabe Y, Mizuno N, Miwa N, et al, "Photosensitivity Induced by Griseofulvin," Photodermatol, 1988, 5(6):272-4.

Lecky BR, "Griseofulvin-Induced Neuropathy," Lancet, 1990, 335(8683):230-1.

Mion G, Verdon R, Le Gulluche Y, et al, "Fatal Toxic Epidermal Necrolysis After Griseofulvin," Lancet, 1989, 2(8675):1331.

Trepanier EF and Amsden GW, "Current Issues in Onchomycosis," Ann Pharmacother, 1998, 32(2):204-14.

Yang DJ and Rankin GO, "Nephrotoxicity of Antifungal Agents," Adverse Drug React Acute Poisoning Rev, 1985, 4(1):37-49.