BIOFULVIN 250MG TABLETS

Indications

• Tinea capitis (scalp ringworm)
• Tinea corporis (ringworm of the body)
• Tinea pedis (athlete's foot)
• Tinea cruris (jock itch)
• Onychomycosis (fungal nail infections)

Dosage

Adults: The usual adult dose for treating dermatophyte infections is 500 mg to 1 g daily

Mechanism of action

Griseofulvin works by disrupting fungal cell mitosis. It binds to alpha and beta tubulin, interfering with the function of spindle and cytoplasmic microtubules. This binding disrupts the mitotic spindle structure, arresting cell division at metaphase. Additionally, griseofulvin binds to keratin in human cells, and upon reaching the site of infection, it binds to fungal microtubules, altering their mitotic processes. As infected keratin is shed, it is replaced with healthy tissue that is resistant to fungal invasion.

Pharmacodynamics

Griseofulvin is a mycotoxic metabolite with fungistatic properties, exhibiting in vitro activity against dermatophyte species such as Microsporum, Epidermophyton, and Trichophyton. It has no antibacterial effects and does not act against other genera of fungi. After oral administration, it is deposited preferentially in keratin precursor cells, particularly in diseased tissue, leading to the formation of a keratin-Griseofulvin complex that enhances resistance to fungal infections.

Pharmacokinetics

Griseofulvin is well absorbed from the gastrointestinal tract, with its absorption enhanced when taken with fatty meals. It is widely distributed throughout the body and has a high affinity for keratin in skin, hair, and nails. The drug is metabolized in the liver and excreted primarily in urine. The half-life of griseofulvin varies based on the formulation and individual patient factors.

Contra-indications

• Porphyria
• Hypersensitivity to griseofulvin or any component of the formulation

Adverse effects

• Headache
• Nausea
• Diarrhea
• Rash
• Fatigue
• Insomnia
• Dizziness
• Elevated liver enzymes
• Photosensitivity

Interactions

• Warfarin - may enhance anticoagulant effect
• Oral contraceptives - may reduce effectiveness
• Phenobarbital - may increase metabolism of griseofulvin
• Alcohol - may increase risk of disulfiram-like reaction

Precautions

• Use with caution in patients with liver disease
• Monitor for signs of hepatotoxicity
• Avoid in patients with a history of porphyria
• Assess for potential drug interactions

Pregnancy

Griseofulvin is contraindicated during pregnancy due to potential teratogenic effects.

Breast-feeding

Griseofulvin is excreted in breast milk; caution is advised when administering to nursing mothers.

Storage

Store at room temperature, away from light and moisture. Keep out of reach of children.

Formulations

• Oral tablets
• Oral suspension

Mechanism of action

Griseofulvin is fungistatic, however the exact mechanism by which it inhibits the growth of dermatophytes is not clear. It is thought to inhibit fungal cell mitosis and nuclear acid synthesis. It also binds to and interferes with the function of spindle and cytoplasmic microtubules by binding to alpha and beta tubulin. It binds to keratin in human cells, then once it reaches the fungal site of action, it binds to fungal microtubes thus altering the fungal process of mitosis. Fungistatic; griseofulvin inhibits fungal cell mitosis by causing disruption of the mitotic spindle structure, thereby arresting the metaphase of cell division. It is deposited in varying concentrations in the keratin precursor cells of skin, hair, and nails, rendering the keratin resistant to fungal invasion. As the infected keratin is shed, it is replaced with healthy tissue.

Pharmacodynamics

Griseofulvin is a mycotoxic metabolic product of <i>Penicillium spp.</i> It was the first available oral agent for the treatment of dermatophytoses and has now been used for more than forty years. Griseofulvin is fungistatic with in vitro activity against various species of Microsporum Epidermophyton, and Trichophyton. It has no effect on bacteria or on other genera of fungi. Following 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. Once the keratin-Griseofulvin complex reaches the skin site of action, it binds to fungal microtubules (tubulin) thus altering fungal mitosis.