Grifulvin V (griseofulvin microsize) is an oral antifungal medication specifically formulated to treat dermatophyte infections that are unresponsive to topical therapy. As a microcrystalline preparation, it offers enhanced bioavailability and consistent systemic delivery, making it a cornerstone treatment in medical mycology. This antifungal agent works by depositing in keratin precursor cells, making newly formed skin, hair, and nails resistant to fungal invasion. It is particularly valued for its targeted action against Trichophyton, Microsporum, and Epidermophyton species, providing a systematic solution for persistent superficial mycotic infections.

Features

• Contains griseofulvin microsize 500mg per tablet
• Microcrystalline formulation for improved gastrointestinal absorption
• Fungistatic activity against dermatophytes
• Selective affinity for keratinized tissues
• Stable shelf life of 24 months
• Manufactured under cGMP standards

Benefits

• Effectively eradicates dermatophyte infections that have penetrated beyond superficial layers
• Prevents recurrence by protecting newly formed keratinized tissues
• Systemic action ensures comprehensive coverage of infected areas
• Well-established safety profile with decades of clinical use
• Convenient once-daily dosing regimen for most indications
• Cost-effective compared to newer antifungal alternatives

Common use

Grifulvin V is primarily indicated for the treatment of tinea infections caused by susceptible dermatophyte species. This includes tinea capitis (scalp ringworm), tinea corporis (body ringworm), tinea pedis (athlete’s foot), tinea unguium (onychomycosis), and tinea barbae. It is particularly effective in cases where topical antifungal agents have proven insufficient due to deep tissue involvement or extensive infection areas. The medication is also used prophylactically in immunocompromised patients susceptible to recurrent fungal infections.

Dosage and direction

Dosage must be individualized based on infection severity, patient weight, and specific pathogen involved. For adults, the typical dosage ranges from 500mg to 1000mg daily, preferably administered with a high-fat meal to enhance absorption. Pediatric dosing is calculated at 10-15mg/kg/day, not to exceed 1000mg daily. Treatment duration varies significantly by infection type: tinea corporis typically requires 2-4 weeks, tinea pedis 4-8 weeks, and onychomycosis may require 4-6 months for fingernails or 6-12 months for toenails. Therapy should continue until clinical and mycological cure is achieved, plus an additional 2 weeks to prevent relapse.

Precautions

Patients should be monitored for hepatic function through periodic liver enzyme tests during prolonged therapy. Complete blood counts are recommended every 2-4 weeks during treatment due to potential hematological effects. Griseofulvin may decrease the efficacy of oral contraceptives; alternative contraceptive methods should be considered. Photosensitivity reactions may occur, necessitating sun protection measures. Patients should avoid alcohol consumption due to potential disulfiram-like reactions. The medication may impair mental and physical abilities required for hazardous tasks.

Contraindications

Grifulvin V is contraindicated in patients with porphyria, hepatocellular failure, or history of hypersensitivity to griseofulvin. It should not be administered during pregnancy (Pregnancy Category C) due to potential teratogenic effects. Contraindications extend to patients with pre-existing blood dyscrasias and those with severe hepatic impairment. Concomitant use with barbiturates may decrease griseofulvin efficacy and is generally contraindicated.

Possible side effect

Common adverse effects include headache (approximately 15% of patients), gastrointestinal disturbances such as nausea and diarrhea (10-12%), and dermatological reactions including urticaria and photosensitivity (5-8%). Less frequently, patients may experience neurological symptoms such as dizziness, insomnia, or peripheral neuropathy with prolonged use. Hematological changes including leukopenia, granulocytopenia, and mild proteinuria have been reported in approximately 2-3% of patients. Serious but rare side effects include hepatitis, Stevens-Johnson syndrome, and angioedema.

Drug interaction

Griseofulvin induces hepatic cytochrome P450 enzymes, potentially reducing the efficacy of warfarin, leading to required anticoagulant dosage adjustments. It may decrease plasma levels of cyclosporine, oral contraceptives, and salicylates. Concurrent administration with barbiturates decreases griseofulvin absorption and serum levels. Alcohol consumption may cause tachycardia and flushing reactions. The medication may potentiate the effects of central nervous system depressants.

Missed dose

If a dose is missed, it should be taken as soon as remembered unless it is nearly time for the next scheduled dose. Patients should never double the dose to make up for a missed administration. Consistent dosing is important for maintaining therapeutic drug levels in keratinized tissues. If multiple doses are missed, healthcare provider consultation is recommended to assess potential impact on treatment efficacy.

Overdose

Symptoms of overdose may include severe nausea, vomiting, epigastric distress, diarrhea, headache, dizziness, and blurred vision. In severe cases, central nervous system depression, hepatotoxicity, or hematological abnormalities may occur. Treatment is supportive and symptomatic, including gastric lavage if ingestion occurred within 4 hours. Activated charcoal may be administered. No specific antidote exists; hemodialysis is not effective due to high protein binding.

Storage

Store at controlled room temperature (20-25°C or 68-77°F) in a tight, light-resistant container. Keep away from moisture and excessive heat. Do not freeze. Keep out of reach of children and pets. Discard any medication that has expired or shows signs of deterioration. Do not transfer to other containers that may not provide adequate protection from light and moisture.

Disclaimer

This information is for educational purposes only and does not constitute medical advice. Grifulvin V is a prescription medication that should be used only under the supervision of a qualified healthcare professional. Individual results may vary, and proper diagnosis by a medical professional is essential before beginning treatment. Always follow your healthcare provider’s instructions regarding dosage and administration.

Reviews

Clinical studies demonstrate Grifulvin V achieves mycological cure rates of 70-85% in tinea capitis and 60-75% in onychomycosis when used as directed. Dermatologists report consistent efficacy in treatment-resistant cases, particularly appreciating its predictable absorption profile. Patients note improvement in symptoms within 2-4 weeks of initiation, with complete clearance typically occurring within the expected treatment timeframe. The medication is generally well-tolerated, with most adverse effects being mild and transient.