Lamisil Dermgel (Terbinafine)

Terbinafine is an allylamine antifungal used to treat superficial dermatophyte infections of the skin.

• Tinea pedis (athlete's foot): Reduces fungal growth and alleviates itching, scaling and redness on the feet.
• Tinea corporis (ringworm): Clears the fungal infection on the body, promoting healing of lesions.
• Tinea cruris (jock itch): Eliminates the causative fungus and relieves irritation in the groin area.

• Terbinafine inhibits the fungal enzyme squalene epoxidase, blocking the conversion of squalene to ergosterol. This disruption impairs ergosterol synthesis, a critical component of fungal cell membranes, leading to accumulation of toxic squalene and loss of membrane integrity, which ultimately kills the fungus.

Terbinafine gel may cause local adverse reactions.

Common Side Effects

• Application site irritation: mild burning or stinging sensation.
• Redness or erythema at the site of application.
• Itching or pruritus localized to the treated area.
• Dryness or peeling of the skin.
• Mild rash confined to the area of use.
• Sensation of warmth or tingling.

Serious or Rare Side Effects

• Severe allergic reaction: swelling, hives, or difficulty breathing.
• Stevens‑Johnson syndrome or toxic epidermal necrolysis.
• Generalized contact dermatitis extending beyond the application site.
• Systemic toxicity such as liver enzyme elevation (rare with topical use).

Before using Lamisil Dermgel, consider the following precautions:

• Avoid use on extensive broken or inflamed skin: limit application to intact epidermis.
• Do not apply to mucous membranes or eyes: avoid accidental contact.
• Monitor for signs of allergic reaction: discontinue if severe rash or swelling occurs.
• Use with caution in patients with known liver disease: systemic absorption is minimal but monitor if large areas are treated.
• Keep out of reach of children: accidental ingestion may cause systemic effects.
• Store at ambient temperature: keep the tube tightly closed, protect from light and moisture.

Terbinafine gel has limited systemic interactions, but consider the following:

Major Interactions (Avoid)

• Concurrent systemic terbinafine therapy: may increase total exposure and risk of systemic toxicity.
• Use with other topical antifungal agents containing azoles: can increase local irritation.

Moderate Interactions (Monitor Closely)

• Application together with potent corticosteroid creams: may mask early signs of irritation.
• Use with skin irritants (e.g., chemical peels): could exacerbate local reactions.
• Combination with other topical agents that alter skin barrier: monitor for increased absorption.