Griseofulvin

Introduction: Griseofulvin is an antifungal medication used to treat fungal infections of the skin, nails, scalp, or hair. This medicine is usually used when other medicines failed to clear up the infection or are not appropriate.

How it works: Griseofulvin is a fungistatic antibiotic that inhibits fungal cell division at metaphase and binds to human keratin making it resistant to fungal infections. It has activity against common dermatophytes including epidermophyton, Microsporum, or Trichophyton spp.

Important Information: Take with food (for better absorption). Take regularly and complete the full course. Do not use during pregnancy and lactation. Avoid alcohol (may cause disulfiram-like reaction).

• Tinea corporis - 2-4 weeks
• Tinea pedis - 4-8 weeks
• Tinea cruris
• Tinea capitis - 4-6 weeks
• Tinea barbae
• Onychomycosis - fingernails: at least 4 months, toenails: at least 6 months

Other Antifungal preparations

Antifungal Antibiotic

Griseofulvin is an orally active antibiotic derived from a species of Penicillium which is used to treat tinea infections. Griseofulvin has a fungistatic effect by its ability to disrupt the mitotic spindle structure of the fungal cell which arrests metaphase in cell division. After oral administration, griseofulvin is deposited in the keratin precursor cells and has a greater affinity for diseased tissue. The drug is tightly bound to the new keratin which becomes highly resistant to fungal invasions.

Griseofulvin inhibits fungal mitosis and binds to keratin to make skin, nails and hair resistant to fungal infections.

Adult Dose (Ultramicrosize):

• Tinea capitis: 375 mg daily (4-6 weeks)
• Tinea corporis: 375 mg daily (2-4 weeks)
• Tinea pedis: 375 mg daily (4-8 weeks)
• Fingernails: 750 mg daily in divided doses for at least 4 months
• Toenails: 750 mg daily in divided doses for at least 6 months

Child Dose (Ultramicrosize):

• 16-27 kg: 125-187.5 mg daily
• Over 27 kg: 187.5-375 mg daily
• Under 2 years: Dosage not established

* Use as directed by the registered physician

Oral tablet. Take with food (immediately after meals). Swallow whole, do not chew or crush.

If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and follow your regular schedule. Do not double the dose.

Common Side Effects:

• Headache
• Skin rash
• Nausea
• Vomiting
• Diarrhea
• Dizziness
• Fatigue
• Insomnia
• Mental confusion
• Oral thrush
• Epigastric distress

Rare: Proteinuria, leukopenia

Precautions:

• Periodic monitoring of organ system function (renal, hepatic, hematopoietic) required for prolonged therapy
• Possibility of cross sensitivity with penicillin
• Photosensitivity reaction may occur - avoid intense natural or artificial sunlight
• Lupus erythematosus or lupus-like syndromes reported
• Not recommended in severe liver disease

Contraindications:

• Porphyria
• Hepatocellular failure
• History of hypersensitivity to griseofulvin
• Pregnancy

Drug Interactions:

• Antagonises oral anticoagulants and oral contraceptives
• Phenobarbital decreases GI absorption
• Enzyme inducers (phenylbutazone, hypnotics) reduce plasma concentrations
• Enhances effects of alcohol and causes disulfiram-like reaction

Food Interactions:

• Unsafe to consume alcohol with Griseofulvin (may cause tachycardia and flush)

Use in Pregnancy: Highly unsafe during pregnancy. Studies have shown significant harmful effects to the developing baby.

Use in Lactation: Probably unsafe during breastfeeding. Limited data suggests the drug may pass into breastmilk and harm the baby.

Pediatric Use: Dosage recommended for children 2 years and older. Dosage not established for children under 2 years.

Geriatric Use: No specific dosage adjustment is necessary for elderly patients. Use with caution.

Renal Impairment: Probably safe in kidney disease. Dose adjustment may not be needed. Regular kidney function monitoring recommended.

Hepatic Impairment: Use with caution in liver disease. Not recommended in severe liver disease. Regular liver function monitoring recommended.

Overdose: Overdose may cause nausea, vomiting, diarrhea, headache. Gastric lavage and supportive care should be given.

Storage: Store below 25°C in a dry place, protected from light. Keep out of reach of children.

Griseofulvin Tablet