Terbinafine

INSTRUCTIONS FOR MEDICAL USE OF THE MEDICINAL PRODUCT TERBINAFINE (TERBINAFINE)

Composition:

Active ingredient: terbinafine hydrochloride;

1 g of cream contains 10 mg of terbinafine hydrochloride, equivalent to 8.8 mg of terbinafine;

Excipients: benzyl alcohol, sodium hydroxide, sorbitan stearate, cetyl palmitate, stearyl alcohol, cetyl alcohol, polysorbate 60, isopropyl myristate, purified water.

Pharmaceutical form. Cream.

Main physicochemical properties: white or almost white homogeneous cream with a weak specific odor.

Pharmacotherapeutic group. Antifungal agents for topical use.

ATC code D01AE15.

Pharmacological properties.

Pharmacodynamics.

Terbinafine is an allylamine with a broad spectrum of antifungal activity. Terbinafine exerts a fungicidal effect against dermatophytes, molds, and some dimorphic fungi at low concentrations. Activity against yeast fungi may be either fungicidal or fungistatic, depending on the species.

Terbinafine specifically inhibits an early stage of sterol biosynthesis in the fungal cell membrane. This leads to ergosterol deficiency and intracellular accumulation of squalene, resulting in fungal cell death. Terbinafine acts by inhibiting the enzyme squalene epoxidase in the fungal cell membrane. This enzyme does not belong to the cytochrome P450 system. Terbinafine does not affect the metabolism of hormonal agents or other medicinal drugs.

Pharmacokinetics.

When applied topically, less than 5% of the dose is absorbed; therefore, systemic absorption of terbinafine into the bloodstream is negligible.

After 7 days of treatment with Terbinafine cream, concentrations of terbinafine exceeding those required for fungicidal activity remain present in the stratum corneum of the epidermis for at least 7 days after discontinuation of treatment.

Clinical characteristics.

Indications.

Fungal skin infections caused by dermatophytes such as Trichophyton (e.g. T. rubrum, T. mentagrophytes, T. verrucosum, T. violaceum), Microsporum canis, and Epidermophyton floccosum, for example: tinea pedis (athlete's foot); tinea cruris (jock itch); tinea corporis (ringworm); cutaneous candidiasis caused by Candida species, usually Candida albicans; pityriasis versicolor caused by Pityrosporum orbiculare (also known as Malassezia furfur).

Contraindications.

Hypersensitivity to terbinafine or to any of the components of the medicinal product.

Interaction with other medicinal products and other forms of interaction.

Unknown.

Special precautions for use

The cream is intended for topical use only. Contact with the eyes should be avoided, as the medicinal product may cause eye irritation. In case of accidental contact with the eyes, they should be thoroughly rinsed with running water. The medicinal product contains cetyl alcohol and stearyl alcohol, which may cause local skin irritation (e.g. contact dermatitis).

Contact between infants and skin areas treated with the medicinal product should be avoided, including contact with the mammary glands.

Fertility studies in animals did not reveal any effect of terbinafine on fertility.

Use during pregnancy or breastfeeding

Animal studies have not shown any embryotoxic effects of terbinafine. Since clinical experience with the use of the drug in pregnant women is limited, the medicinal product should not be used during pregnancy unless, in the opinion of the physician, the expected benefit to the mother outweighs the potential risk to the fetus.

Terbinafine passes into breast milk; therefore, the drug should not be used in women who are breastfeeding. Contact between infants and skin areas treated with the medicinal product should be avoided, including contact with the mammary glands.

Ability to influence reaction speed while driving or operating machinery

Topical application of terbinafine does not affect the ability to drive or operate machinery.

Method of Administration and Dosage

The cream is intended for topical use only.

Adults and children aged 12 years and older

Apply terbinafine to the skin once or twice daily depending on the condition. Before application, thoroughly clean and dry the affected areas. Apply the cream in a thin layer to the affected skin and surrounding areas, gently rubbing in. For infections associated with intertrigo (under the breasts, in the interdigital areas, groin, and between the buttocks), the application sites may be covered with gauze, especially at night.

Duration and Frequency of Treatment

The duration of treatment depends on the severity of the disease:

• Tinea pedis (interdigital type), tinea cruris, and tinea corporis: once daily for 1 week;
• Scaled-hyperkeratotic tinea pedis ("moccasin type"): twice daily for 2 weeks;
• Cutaneous candidiasis: once or twice daily for 1–2 weeks;
• Pityriasis versicolor: once or twice daily for 2 weeks.

Dose adjustment is not required for elderly patients.

Symptom relief usually occurs within a few days. Irregular use or premature discontinuation of treatment may lead to relapse.

If there is no sign of improvement after two weeks of treatment, consult a physician.

Children

Experience with the use of the drug in children under 12 years of age is limited; therefore, the drug should not be used in this age group.

Overdose

Due to the low systemic absorption of terbinafine with topical application, the likelihood of overdose is extremely low. Accidental ingestion of the contents of one 15 g tube (containing 150 mg of terbinafine hydrochloride) is comparable to taking half of a 250 mg terbinafine tablet (an oral dosage form). In cases of overdose due to accidental ingestion of a large amount of cream, adverse effects would be similar to those seen with an overdose of terbinafine tablets (e.g., headache, nausea, epigastric pain, and dizziness).

Management of overdose following accidental ingestion involves removal of the active substance, primarily by administering activated charcoal, and providing symptomatic treatment as necessary.

Adverse reactions.

Local manifestations such as itching, peeling or burning of the skin, pain and irritation at the application site, pigmentary disturbances, erythema, crusting, and other manifestations may occur at the site of application. These minor effects should be differentiated from hypersensitivity reactions, including rash, which have been reported in isolated cases and which require discontinuation of treatment. In case of accidental contact with eyes, terbinafine hydrochloride may cause irritation. In rare cases, latent fungal infection may worsen.

Possible adverse effects:

Immune system disorders

Frequency unknown (cannot be estimated from available data): hypersensitivity reactions, including urticaria. In isolated cases – angioedema and anaphylactic shock.

Eye disorders

Rare (≥1/10,000, <1/1,000): eye irritation.

Skin and subcutaneous tissue disorders

Common (≥ 1/100, < 1/10): skin peeling, itching.

Uncommon (≥ 1/1,000, < 1/100): skin damage, crusting, skin lesions, pigmentary disturbances, erythema, skin burning sensation.

Rare (≥1/10,000, <1/1,000): skin dryness sensation, contact dermatitis, eczema.

Frequency unknown (cannot be estimated from available data): rash or blistering.

General disorders and administration site conditions

Uncommon (≥ 1/1,000, < 1/100): pain, pain at application site, irritation at application site.

Rare (≥1/10,000, <1/1,000): worsening of symptoms.

Reporting of suspected adverse reactions

Reporting of suspected adverse reactions after authorization of the medicinal product is important. It allows continued monitoring of the benefit-risk balance of the medicinal product. Healthcare and pharmacy professionals, as well as patients or their legal representatives, should report all suspected adverse reactions and lack of efficacy via the Automated Pharmacovigilance Information System at the following link: https://aisf.dec.gov.ua.

Shelf life. 3 years.

Storage conditions. Store in the original packaging at a temperature not exceeding 25 °C.

Keep out of reach of children.

Packaging. 15 g in a tube, 1 tube in a cardboard box.

Availability. Over-the-counter.

Manufacturer. JSC "Lubnipharm".

Manufacturer's address and location of operations. 16 Barvinkova Street, Lubny, Poltava region, 37500, Ukraine.