Lamisil cream (Terbinafine)

What Is Lamisil?

Lamisil cream is a topical treatment option for a range of fungal infections of the skin. In Canada, terbinafine cream is commonly used in dermatology and primary care for localized fungal skin infections. It is known for being effective in many patients, generally well tolerated, and associated with a low rate of reported side effects. The main active ingredient in the cream is terbinafine. This substance belongs to the allylamine group and has a broad antifungal effect. Even at relatively low concentrations, it has a fungicidal effect on most dermatophytes and dimorphic fungi.

Composition and Active Ingredients

Lamisil formulations for topical use, such as creams or gels, contain terbinafine hydrochloride at a concentration of 1% w/w. One gram of the cream contains terbinafine hydrochloride 10 mg, equivalent to 8.8 mg of terbinafine. Additional ingredients may include cetyl alcohol, stearyl alcohol, and benzyl alcohol, which help give the product its texture and stability.

Terbinafine works by inhibiting squalene epoxidase, an enzyme needed for ergosterol synthesis in fungal cell membranes. This leads to fungal cell death and helps treat infections such as athlete's foot and onychomycosis. Less than 5% of the dose is absorbed after application to the affected skin area. As a result, absorption of terbinafine into the bloodstream is negligible.

Uses

Lamisil can have both fungicidal and fungistatic effects. It also has a long-lasting effect, which may help patients not only achieve the desired treatment result but also reduce the chance of reinfection after a short treatment course.

Lamisil (terbinafine) is indicated for the topical treatment of the following skin infections: tinea (pityriasis) versicolor caused by Malassezia furfur (formerly Pityrosporum ovale), tinea pedis (athlete's foot), tinea corporis (ringworm), and tinea cruris (jock itch) caused by Trichophyton rubrum, Trichophyton mentagrophytes, or Epidermophyton floccosum. Diagnosis should be confirmed either by culture, except for Malassezia furfur (formerly Pityrosporum ovale), or by examining scrapings from infected tissue mounted in a potassium hydroxide solution.

Lamisil in the Treatment of Fungal Infections

Terbinafine specifically blocks an early stage of sterol biosynthesis in fungal cell membranes. This causes ergosterol deficiency and an intracellular buildup of squalene, which leads to fungal cell death. Terbinafine works by inhibiting the squalene epoxidase enzyme in the cell membrane. Because this enzyme is not part of the cytochrome P450 system, terbinafine does not affect hormone metabolism in the human body.

Lamisil cream is used to treat several fungal skin infections, including tinea pedis (athlete's foot), tinea cruris (jock itch), and tinea corporis (ringworm).

For adults and children 12 years and older, Lamisil cream should be applied 1-2 times per day depending on the severity of the infection.

The length of treatment depends on how severe the infection is.

• Interdigital toe web infections and/or dermatophyte infections of the torso - apply the cream once a day for 1 week.
• Skin candidiasis - apply the cream 1-2 times daily for 1 week.
• Multicoloured lichen - apply the cream 1-2 times daily for 2 weeks.

Older adults do not require additional dose adjustments. Clinical experience with this medicine in children under 12 years of age is limited, so it should not be used in this age group.

The cream should be applied to the affected area and the surrounding skin after the area has been cleaned and dried thoroughly. Avoid contact with the eyes, nose, mouth, and other mucous membranes. If irritation occurs, stop using it. Using the cream consistently as directed is important for effective treatment, even if symptoms start to improve before the full course is finished.

Lamisil in the Treatment of Yeast Infections

The drug also shows very efficient results in the therapy of yeast infections. Lamisil cream for penile yeast infection therapy has better results than therapy with most currently prescribed antiseptic agents. The active components of the drug penetrate deeply into the affected penile tissues and make it possible to cure the disease starting from the inner cellular layers. However, these active ingredients also perfectly fulfill their external functions, eliminating pus cells from the tissue, i.e., cleansing the affected area of the external irritant.

Lamisil cream for yeast diaper rash should be administered four times per day. If positive effects are not seen after three days, contact your healthcare provider to discuss a suitable alternative or whether the daily dose should be adjusted.

Precautions

Lamisil is not for ophthalmic, oral, or intravaginal use. The cream is for external use only. Use Lamisil exactly as directed by your Canadian physician.

Signs of relief are usually seen within two to three days after starting treatment. Irregular use or stopping treatment too early may lead to the infection coming back.

If there is no notable improvement after two weeks of treatment, contact your doctor. Additional dose adjustments may be needed.

Allergy Warnings

Lamisil (terbinafine) is contraindicated in people with known or suspected hypersensitivity to terbinafine or any of its other ingredients. Tell your physician if the application area becomes more irritated or shows signs of possible sensitization, such as redness, itching, burning, blistering, swelling, or oozing.

Health Conditions Warnings

Terbinafine may be present in breast milk. For this reason, the drug should not be used by breastfeeding women. Pregnant women should also avoid applying Lamisil.

Lamisil 1% contains 11.3% v/v alcohol. If irritation or sensitivity develops, treatment should be stopped and appropriate therapy started. Lamisil may irritate the eyes. If it accidentally gets into your eyes, rinse them thoroughly with running water and consult a physician if any symptoms continue.

Avoid covering the affected areas with dressings unless your physician tells you to do so.

There has been no experience of overdose with topical terbinafine formulations. However, the alcohol content (11.3%) of the cream should be taken into account.

Terbinafine Side Effects

In most clinical cases, side effects are rare and do not require medical attention. Possible side effects include:

• Local symptoms such as itching, peeling or burning of the skin, pain and irritation at the application site, changes in pigmentation, and erythema. These minor effects should be distinguished from hypersensitivity reactions, including rashes, which may require stopping treatment.
• If the cream accidentally gets into the eyes, terbinafine hydrochloride may cause eye irritation.
• Pain at the application site.
• Irritation at the application site.
• Rarely reported worsening of symptoms of the fungal infection.

In clinical trials, none of the 262 patients treated with Lamisil (terbinafine) stopped therapy because of adverse events. In patients treated with Lamisil (terbinafine), reactions considered possibly, probably, or definitely related to treatment included skin disorders (1.9%), application-site reactions such as burning or irritation (1.5%), and pruritus (1.1%). These events were seen only in patients with tinea cruris: skin discoloration, hyperpigmentation (3/36), skin exfoliation (1/36), and contact dermatitis (1/36).

Interaction with Other Medicines

Potential interactions between Lamisil (terbinafine) and other medicines have not been systematically evaluated.

After Using Lamisil

After using Lamisil cream, it is important to store and dispose of it properly.

Storage

Lamisil cream should be stored in its original packaging to protect it from light and moisture. Keep the tube tightly closed and out of reach of children. Do not use the cream after the expiry date shown on the package. Once opened, an aluminum tube can typically be used for up to four months, while a laminated tube has a shelf life of one month.

Disposal

When disposing of Lamisil cream, do not throw it in household garbage or pour it down the drain, as this can harm the environment. Instead, ask your pharmacist in Canada about proper disposal methods. Unused or expired medications should be returned to a pharmacy for safe disposal to help protect the environment.