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Medically reviewed on Sep 10, 2018


(gri see oh FUL vin)

Index Terms

  • Griseofulvin Microsize
  • Griseofulvin Ultramicrosize

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Suspension, Oral:

Generic: 125 mg/5 mL (118 mL [DSC], 120 mL)

Tablet, Oral:

Grifulvin V: 500 mg [DSC] [scored]

Gris-PEG: 125 mg [DSC], 250 mg [DSC] [scored]

Generic: 125 mg, 250 mg, 500 mg

Brand Names: U.S.

  • Grifulvin V [DSC]
  • Gris-PEG [DSC]

Pharmacologic Category

  • Antifungal Agent, Oral


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


Ultramicrosize griseofulvin absorption is almost complete; absorption of microsize griseofulvin is variable (27% to 72% of an oral dose); enhanced by ingestion of a fatty meal (GI absorption of ultramicrosize is ~1.5 times that of microsize); absorbed from the duodenum


Deposited in the keratin layer of skin, hair, and nails; concentrates in liver, fat, and skeletal muscles; Vd: ~1.5 L (Vozeh 1988)


Extensively hepatic


Urine (<1% as unchanged drug); feces (~33%); perspiration

Time to Peak

Serum: 4 hours

Half-Life Elimination

9 to 24 hours

Use: Labeled Indications

Dermatophyte infections: Treatment of the following dermatophyte infections of the skin, hair, and nails not adequately treated by topical therapy: Tinea corporis, tinea pedis, tinea cruris, tinea barbae, tinea capitis, tinea unguium (onychomycosis) when caused by one or more of the following species of fungi: Trichophyton rubrum, Trichophyton tonsurans, Trichophyton mentagrophytes, Trichophyton interdigitalis, Trichophyton verrucosum, Trichophyton megnini, Trichophyton gallinae, Trichophyton crateriform, Trichophyton sulphureum, Trichophyton schoenleini, Microsporum audouini, Microsporum canis, Microsporum gypseum, and Epidermophyton floccosum.

Limitations of use: Use for the prophylaxis of fungal infections has not been established; not effective for the treatment of tinea versicolor.


Hypersensitivity to griseofulvin or any component of the formulation; hepatic failure; porphyria; pregnancy

Dosing: Adult

Dermatophyte infections: Oral:

Microsize: 500 mg/day in single or divided doses; for more widespread lesions initial doses of 750 to 1,000 mg/day in single or divided doses may be needed; may decrease gradually to 500 mg/day or less if patient responds to higher dose.

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

Duration of therapy depends on the site of infection:

Tinea corporis: 2 to 4 weeks

Tinea cruris: Duration not specified in manufacturer’s labeling; in pediatric patients 6 weeks has been recommended (Red Book, 2015)

Tinea capitis: 4 to 6 weeks

Tinea pedis: 4 to 8 weeks

Tinea unguium: 4 to 6 months or longer

Dosing: Geriatric

Refer to adult dosing.

Dosing: Pediatric

Dermatophyte infections: Children >2 years and Adolescents: Oral:


Manufacturer's labeling: Dosage should be individualized; 10 mg/kg/day in a single or divided doses (maximum daily dose: 500 mg/day) or:

13.6 to 22.7 kg: 125 to 250 mg/day in divided doses

>22.7 kg: 250 to 500 mg/day in divided doses

Alternate dosing: 10 to 20 mg/kg/day in single or 2 divided doses (maximum: 1,000 mg/day) (Red Book [AAP 2015]); Note: Tinea capitis: 20 to 25 mg/kg/day has been recommended (Ali 2007; Lipozenic 2002; Sethi 2006).

Ultramicrosize: 5 to 15 mg/kg/day in single dose or 2 divided doses (maximum dose/day: 750 mg/day) (Red Book [AAP 2015])

Duration of therapy depends on the site of infection:

Tinea corporis:

Manufacturer's labeling: 2 to 4 weeks

Alternate recommendations: 6 weeks (Red Book [AAP 2015])

Tinea cruris: 6 weeks (Red Book [AAP 2015])

Tinea capitis:

Manufacturer's labeling: 4 to 6 weeks

Alternate recommendations: Children: 6 to 12 weeks; use up to 16 weeks may be required (AAP Red Book recommends continuing treatment for 6 weeks or more and 2 weeks after clinical resolution of symptoms) (Red Book [AAP 2015]; Ali 2007; Lipozenic 2002; Sethi 2006)

Tinea pedis: 4 to 8 weeks

Tinea unguium: 4 to 6 months or longer

Dosing: Renal Impairment

There are no dosage adjustments provided in the manufacturer's labeling.

Dosing: Hepatic Impairment

Use is contraindicated in hepatic failure.


Oral: Administer with a fatty meal to increase absorption (Red Book [AAP 2015])

Gris-PEG tablets: May be swallowed whole or crushed and sprinkled onto 1 tablespoonful of applesauce and swallowed immediately without chewing.

Suspension: Shake well before use.


Store at 20°C to 25°C (68°F to 77°F). Protect from light.

Drug Interactions

Alcohol (Ethyl): Griseofulvin may enhance the adverse/toxic effect of Alcohol (Ethyl). A disulfiram-like reaction may occur. Monitor therapy

Aminolevulinic Acid (Systemic): Photosensitizing Agents may enhance the photosensitizing effect of Aminolevulinic Acid (Systemic). Avoid combination

Aminolevulinic Acid (Topical): Photosensitizing Agents may enhance the photosensitizing effect of Aminolevulinic Acid (Topical). Monitor therapy

Barbiturates: May decrease the serum concentration of Griseofulvin. Exceptions: Methohexital; Thiopental. Monitor therapy

Carbocisteine: Griseofulvin may enhance the adverse/toxic effect of Carbocisteine. Specifically, griseofulvin may enhance adverse effects of alcohol that is present in liquid formulations of carbocisteine-containing products. Monitor therapy

CycloSPORINE (Systemic): Griseofulvin may decrease the serum concentration of CycloSPORINE (Systemic). Monitor therapy

Estrogen Derivatives (Contraceptive): Griseofulvin may increase the metabolism of Estrogen Derivatives (Contraceptive). Contraceptive failure is possible. Management: Use an alternative, nonhormonal form of contraception, or use an alternative to griseofulvin. Consider therapy modification

Porfimer: Photosensitizing Agents may enhance the photosensitizing effect of Porfimer. Monitor therapy

Progestins (Contraceptive): Griseofulvin may diminish the therapeutic effect of Progestins (Contraceptive). Contraceptive failure is possible. Avoid combination

Saccharomyces boulardii: Antifungal Agents (Systemic, Oral) may diminish the therapeutic effect of Saccharomyces boulardii. Avoid combination

Ulipristal: Griseofulvin may decrease the serum concentration of Ulipristal. Avoid combination

Verteporfin: Photosensitizing Agents may enhance the photosensitizing effect of Verteporfin. Monitor therapy

Vitamin K Antagonists (eg, warfarin): Griseofulvin may decrease the serum concentration of Vitamin K Antagonists. Monitor therapy

Test Interactions

False-positive urinary VMA levels (Rampini 1989)

Adverse Reactions

Frequency not defined.

Central nervous system: Confusion, dizziness, fatigue, headache, insomnia

Dermatologic: Dermatological reaction (erythema multiforme-like drug reaction), skin photosensitivity, skin rash (most common), urticaria (most common)

Gastrointestinal: Diarrhea, epigastric distress, gastrointestinal hemorrhage, nausea, oral candidiasis, vomiting

Genitourinary: Nephrosis

Hematologic & oncologic: Granulocytopenia

Hepatic: Hepatotoxicity

<1%, postmarketing, and/or case reports: Angioedema, increased serum bilirubin, increased serum transaminases, leukopenia, lupus-like syndrome, paresthesia, proteinuria, Stevens-Johnson syndrome, toxic epidermal necrolysis


Concerns related to adverse effects:

• Hematologic effects: Leukopenia has been reported (rare); discontinue therapy if granulocytopenia occurs.

• Hepatic effects: May cause jaundice and elevated liver function tests or bilirubin (may be serious or even fatal); monitor hepatic function and discontinue therapy if necessary.

• Penicillin allergy: Hypersensitivity cross reaction between penicillins and griseofulvin is possible, however, known penicillin-sensitive patients have been treated successfully without complications.

• Photosensitivity: Avoid exposure to intense sunlight to prevent photosensitivity reactions.

• Skin reactions: Severe skin reactions (eg, Stevens-Johnson syndrome, toxic epidermal necrolysis, erythema multiforme) have been reported (may be serious or even fatal); discontinue use if severe skin reactions occur.

Disease-related concerns:

• Lupus erythematosus: Development of lupus erythematosus, lupus-like syndromes or exacerbation of existing lupus erythematosus has been reported.

Concurrent drug therapy issues:

• Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.

Other warnings/precautions:

• Appropriate use: Use for the prophylaxis of fungal infections has not been established; not effective for the treatment of tinea versicolor.

Monitoring Parameters

Periodic renal, hepatic, and hematopoietic function tests especially with long-term use

Pregnancy Risk Factor


Pregnancy Considerations

Teratogenic effects have been observed in animal reproduction studies. Griseofulvin crosses the placenta (Pacifici, 2006). Because adverse events have also been observed in humans (two cases of conjoined twins), use during pregnancy is contraindicated. Effective contraception should be used during therapy and for 1 month after therapy is discontinued in women of reproductive potential. Men should avoid fathering a child for at least 6 months after therapy.

Patient Education

• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)

• Patient may experience headache, dizziness, nausea, vomiting, abdominal pain, loss of strength and energy, insomnia, or diarrhea. Have patient report immediately to prescriber signs of lupus (rash on the cheeks or other body parts, sunburn easy, muscle or joint pain, chest pain or shortness of breath, or swelling in the arms or legs), signs of liver problems (dark urine, feeling tired, lack of appetite, nausea, abdominal pain, light-colored stools, vomiting, or yellow skin or eyes), confusion, burning or numbness feeling, redness or white patches in mouth or throat, or signs of Stevens-Johnson syndrome/toxic epidermal necrolysis (red, swollen, blistered, or peeling skin [with or without fever]; red or irritated eyes; or sores in mouth, throat, nose, or eyes) (HCAHPS).

• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for healthcare professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience and judgment in diagnosing, treating and advising patients.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.