Terbinafin

Terbinafine is an allylamine antifungal used for the treatment of dermatophyte infections of the skin and nails. Oral terbinafine is the most effective treatment for fungal nail infections (onychomycosis), with cure rates of approximately 70 to 80% for toenail infections. It works by inhibiting squalene epoxidase, an enzyme essential for ergosterol synthesis in the fungal cell membrane. Terbinafine accumulates in the nail and persists for months after treatment ends.

How to Take Terbinafine

For nail infections, take one tablet once daily for 6 weeks (fingernail infections) or 12 weeks (toenail infections). For skin infections, take one tablet daily for 2 to 6 weeks, or apply terbinafine cream to the affected area twice daily for skin infections. Take oral tablets with food to improve absorption and reduce stomach upset.

It is important to complete the full course of treatment even if the nails or skin look better before the end. Fungal nail infections clear very slowly, and the visible improvement may only become apparent weeks or months after the infection has been cleared from the nail bed.

Oral: 250 mg once daily. Fingernails: 6 weeks. Toenails: 12 weeks (some patients may need longer). Topical cream: apply once or twice daily for 1 to 2 weeks (skin infections).

Common Side Effects

Common side effects include:

• Stomach discomfort, nausea, or diarrhoea
• Headache
• Skin rash or itching
• Taste disturbance (loss or alteration of taste, affects some people and can persist for weeks)
• Mildly raised liver enzymes

Loss or alteration of taste is a well-known side effect of terbinafine and can be distressing for some people. It usually resolves after stopping treatment, but in rare cases it can be prolonged. Contact your doctor if taste changes are significant or persist after you finish the course.

Monitor liver function before and during prolonged treatment. Taste disturbance usually resolves after stopping but may persist for weeks. Stop treatment if severe skin reactions develop.

Contraindicated in severe hepatic impairment, chronic or active liver disease, and known hypersensitivity to terbinafine.