U.S. Brand Names:
Grifulvin® V; Gris-PEG®
Synonyms:
Griseofulvin Microsize; Griseofulvin Ultramicrosize
Generic Available:
Yes: Ultramicrosized product
Canadian Brand Names:
Fulvicin® U/F
Use:
Treatment of susceptible tinea infections of the skin, hair, and nails
Pregnancy Risk Factor:
C
Lactation:
Excretion in breast milk unknown
Contraindications:
Hypersensitivity to griseofulvin or any component of the formulation; severe liver disease; porphyria (interferes with porphyrin metabolism)
Warnings/Precautions:
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
Adverse Reactions:
Frequency not defined.
Central nervous system: Headache, fatigue, dizziness, insomnia, mental confusion
Dermatologic: Rash (most common), urticaria (most common), photosensitivity, erythema multiforme, angioneurotic edema (rare)
Gastrointestinal: Nausea, vomiting, epigastric distress, diarrhea, GI bleeding
Genitourinary: Menstrual irregularities (rare)
Hematologic: Leukopenia, granulocytopenia
Neuromuscular & skeletal: Paresthesia (rare)
Renal: Hepatotoxicity, proteinuria, nephrosis
Miscellaneous: Oral thrush, drug-induced lupus-like syndrome (rare)
Overdosage/Toxicology:
Symptoms of overdose include lethargy, vertigo, blurred vision, nausea, vomiting, and diarrhea. Treatment is supportive.
Drug Interactions:
Induces CYP1A2 (weak), 2C8/9 (weak), 3A4 (weak)
Decreased effect:
Barbiturates may decrease levels of griseofulvin
Decreased warfarin, cyclosporine, and salicylate activity with griseofulvin
Griseofulvin decreases oral contraceptive effectiveness
Increased toxicity: With ethanol, may cause tachycardia and flushing
Ethanol/Nutrition/Herb Interactions:
Ethanol: Avoid ethanol (may increase CNS depression). Ethanol will cause "disulfiram"-type reaction consisting of flushing, headache, nausea, and in some patients, vomiting and chest and/or abdominal pain.
Food: Griseofulvin concentrations may be increased if taken with food, especially with high-fat meals.
Mechanism of Action:
Inhibits fungal cell mitosis at metaphase; binds to human keratin making it resistant to fungal invasion
Pharmacodynamics/Kinetics:
Absorption: Ultramicrosize griseofulvin absorption is almost complete; absorption of microsize griseofulvin is variable (25% to 70% of an oral dose); enhanced by ingestion of a fatty meal (GI absorption of ultramicrosize is ~1.5 times that of microsize)
Distribution: Crosses placenta
Metabolism: Extensively hepatic
Half-life elimination: 9-22 hours
Excretion: Urine (<1% as unchanged drug); feces; perspiration
Dosage:
Oral:
Children >2 years:
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
Administration:
Oral: Administer with a fatty meal (peanuts or ice cream) to increase absorption, or with food or milk to avoid GI upset
Monitoring Parameters:
Periodic renal, hepatic, and hematopoietic function tests
Test Interactions:
False-positive urinary VMA levels
Patient Education:
Inform prescriber of all prescriptions, OTC medications, or herbal products you are taking, and any allergies you have. Do not take any new medication during therapy unless approved by prescriber. Take as directed, around-the-clock with food. Take full course of medication; do not discontinue without consulting 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); or 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. Pregnancy/breast-feeding precautions: Inform prescriber if you are or intend to become pregnant. Consult prescriber if breast-feeding.
Nursing Implications:
Monitor periodic renal, hepatic, and hematopoietic function tests
Dental Health: Effects on Dental Treatment:
Key adverse event(s) related to dental treatment: May cause soreness or irritation of mouth or tongue.
Dental Health: Vasoconstrictor/Local Anesthetic Precautions:
No information available to require special precautions
Mental Health: Effects on Mental Status:
May cause dizziness, confusion, or insomnia
Mental Health: Effects on Psychiatric Treatment:
May rarely cause leukopenia; use caution with clozapine and carbamazepine; barbiturates may decrease levels of griseofulvin
Dosage Forms:
Suspension, oral, microsize (Grifulvin® V): 125 mg/5 mL (120 mL) [contains alcohol 0.2%]
Tablet, microsize (Grifulvin® V): 500 mg
Tablet, ultramicrosize: 125 mg, 250 mg, 330 mg
Gris-PEG®: 125 mg, 250 mg
International Brand Names:
Afuvin® (BD); Aofen® (TH); Biogrisin® (ID, RO); Erlivin® (SG); Fulcin® (AU, BG, BR, CY, EG, ES, HK, ID, IE, IT, JO, KW, LB, MT, RO, SY, ZA); Fulcinex® (BD); Fulcin S® (DE); Fulkain® (DO); Fulvicin® U/F (CA); Fulvin-G® (BD); Fulvistatin P/G® (CL); Fulvistatin U/F® (CL); Fungistop® (ID); Gefulvin® (TR); G-G. Vin® (BD); Greosin® (CL, ES); Gricin® (CZ, DE, PL); Grifulin® (IL); Grifulvin® (TH); Grisactin® (IN); Griséfuline® (FR); Griseoderm® (HK); Griseofort® (ID); Griseofulvina L.CH.® (CL); Griseofulvin® (BE, CY, ID, PL, RO); Griseofulvin Chemist Lab® (BD); Griseofulvin Hovid® (SG); Griseofulvin Leo® (LU); Griseomed® (AT); Griseostatin® (AU, HK); griseo von ct® (DE); Grisflavin® (TH); Grisol® (CH); Griso-T (BD); Grisovina FP® (IT); Grisovin® (AT, AU, GB, HK, KW, MX, NZ, TR); Grisovin-FP® (BD); Grivin® (ID, SG, TH); H.G. Griseofulvin® (EC); Japcin® (BD); Krisovin® (SG); Likuden® (DE); Medofluvin® (SG); Microcidal® (ZA); Microfulvin® (ID); Mycostop® (ID); Neofulvin® (TH); Nidovin® (BD); Opsovin® (BD); Orgavin® (BD); Seovin® (BD); Sporostatin® (BR); Trivanex®1 (TH); Walavin® (IN)
References
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.