Terbinafin-Teva, pills 250mg 28pcs

Composition

1 tablet contains:  

Active ingredient:

terbinafine hydrochloride 250 mg;

Auxiliary substances:

microcrystalline cellulose,

hyprolose (hydroxypropylcellulose),

croscarmellose sodium,

colloidal silicon dioxide,

calcium stearate,

lactose monohydrate

Pharmacological action

Terbinafine is an antifungal agent. It has a broad spectrum of action against fungi that cause diseases of the skin, hair and nails, including:

• dermatophytes such as Trichophyton (e. g., T. rubrum, T. mentagrophytes, T. verrucosum, T. tonsurans, T. violaceum), Microsporum (e. g., M. canis), Epidermophyton floccosum;
• yeast fungi of the genus Candida (e. g., C. albicans) and Pityrosporum.

In low concentrations, terbinafine has a fungicidal effect against dermatophytes, mold and some dimorphic fungi. Activity against yeast fungi, depending on their type, can be fungicidal or fungistatic.

The mechanism of action is associated with specific suppression of the early stage of sterol biosynthesis in the fungal cell. This leads to ergosterol deficiency and intracellular squalene accumulation, which causes fungal cell death. The action of terbinafine is carried out by inhibiting the enzyme squalene oxidase in the cell membrane of the fungus. This enzyme does not belong to the cytochrome P450 system. Terbinafine does not significantly affect the metabolism of hormones or other medications.

Pharmacokinetics

When terbinafine is administered orally, concentrations of the drug are created in the skin, hair and nails that provide a fungicidal effect.

After a single oral dose of 250 mg of terbinafine, its maximum plasma concentration is reached in 2 hours and is 0.97 mcg / ml. The half-absorption period is 0.8 hours, and the half-distribution period is 4.6 hours. Although the bioavailability of terbinafine modestly changes under the influence of food, but not to such an extent that a dose adjustment of the drug is required.

Terbinafine is largely bound to plasma proteins (99%). It quickly penetrates the dermal layer of the skin and concentrates in the lipophilic stratum corneum. Terbinafine also penetrates the secret of the sebaceous glands, which leads to the creation of high concentrations in hair follicles, hair and in the skin rich in sebaceous glands. It is also shown that terbinafine penetrates the nail plates in the first few weeks after the start of therapy.

Terbinafine is metabolized rapidly and significantly with the participation of at least seven cytochrome P 450 isoenzymes, with the main role played by the isoenzymes CYP2C9, CYP1A2, CYP3A4, CYP2C8 and CYP2C19. As a result of biotransformation of terbinafine, metabolites are formed that do not have antifungal activity and are mainly excreted in the urine. The final elimination half-life is 17 hours. There is no evidence of accumulation of the drug in the body.

There were no changes in the steady-state plasma concentrations of terbinafine depending on age, but in patients with impaired renal or hepatic function, the rate of drug elimination may be slowed, which leads to higher concentrations of terbinafine in the blood.

With topical application of the spray or cream, less than 5% of the dose is absorbed, so the systemic effect of the drug is minimal.

Indications

• Mycoses of the scalp (trichophytosis, microsporia).
• Fungal diseases of the skin and nails (onychomycosis) caused by Trychophyton (T. rubrum, T. mentagrophytes, T. verrucosum, T. violaccum), Microsporum (M. sapis, M. gypseum) and Epidermophyton floccosum.
• Severe, widespread dermatomycosis of smooth skin of the trunk and limbs, requiring systemic treatment.
• Candidiasis of the skin and mucous membranes.

Contraindications

Hypersensitivity, severe hepatic-cellular and renal insufficiency, blood diseases, tumors, metabolic diseases, vascular pathology of the extremities, pregnancy, breast-feeding, children (up to 2 years).

Side effects

Sensation of heaviness and pain in the epigastric region, impaired taste, decreased appetite, nausea, diarrhea, cholestasis, neutropenia, thrombocytopenia, allergic skin reactions; burning sensation, redness of the skin and itching in the area of applying the cream.

Interaction

Dosage adjustment of terbinafine is required when used concomitantly with inhibitors and inducers of cytochrome P450 isoenzymes, which can slow down and accelerate the elimination of terbinafine from the body.

Cimetidine reduces the elimination rate of terbinafine by 30%, and rifampicin increases the elimination rate of terbinafine by 100%. In vitro and in vivo studies have shown that terbinafine, by inhibiting the CYP2P6 isoenzyme, interferes with the metabolism of tricyclic antidepressants, selective serotonin reuptake inhibitors (desipramine, fluvoxamine), beta-blockers (metoprolol, propranolol), antiarrhythmics (flecainide, propafenone), monoamine oxidase B inhibitors (selegiline), and antipsychotic drugs (chlorpromazine, haloperidol).

Terbinafine does not significantly affect the rate of elimination of tolbutamine, terfinadine, triazolam, or oral contraceptives that are metabolized by other cytochrome P450 isoenzymes (with the exception of the CYP2P6 isoenzyme). Terbinafine does not affect the rate of elimination of antipyrine and digoxin. When taking terbinafine and oral contraceptives at the same time, a violation of the menstrual cycle may develop.

Terbinafine can enhance the effectiveness of caffeine by increasing its plasma concentration and reducing the rate of elimination from the body by 21%. Terbinafine can reduce the rate of elimination of desipramine from the body by 82%. Terbinafine may reduce the effectiveness of cyclosporine by reducing its plasma concentration by 15%.

When used concomitantly with warfarin, it can affect the parameters of the prothrombin test: blood clotting time and the international normalized ratio. When combined with ethanol or drugs that have a hepatoxic effect, there is a risk of developing drug-induced liver damage.

How to take, course of use and dosage

The duration of treatment depends on the indication and severity of the disease.

Children:  Inside, after a meal, is prescribed once a day. A single dose depends on body weight and is: for children with a body weight of less than 20 kg-62.5 mg (half a tablet of 125 mg); from 20 to 40 kg-125 mg (one tablet of 125 mg); more than 40 kg-250 mg (two tablets of 125 mg).

Adults:  250 mg once a day in the evening or 2 times a day for 125 mg.

Skin infections:

Recommended duration of treatment:

• dermatomycosis of the feet (interdigital, plantar, or sock-like): 2-6 weeks;
• dermatomycosis of the trunk, limbs, and lower legs: 2-4 weeks;
• skin candidiasis: 2-4 weeks.

Complete disappearance of infection symptoms and complaints associated with it may occur only a few weeks after mycological treatment.

Infections of the hair and scalp:

Recommended duration of treatment:

• mycosis of the scalp: 4 weeks.

Mycoses of the scalp are observed mainly in children.

Onychomycosis:

The duration of effective treatment in most patients is from 6 to 12 weeks. With onychomycosis of the hands, in most cases,6 weeks of treatment is sufficient. With onychomycosis of the feet, in most cases,12 weeks of treatment is sufficient. Some patients who have a reduced rate of nail growth may require longer treatment. The optimal clinical effect is observed several months after mycological treatment and discontinuation of therapy. This is determined by the time period that is necessary for the growth of a healthy nail.

Use of terbinafine in the elderly: There is no reason to assume that the elderly need to change the dosage of the drug or that they have side effects that differ from those in younger patients. If the drug is used in tablets in this age group, the possibility of concomitant liver or kidney dysfunction should be taken into account.

Overdose

Symptoms:  nausea, vomiting, headache, dizziness, gastralgia, frequent urination, rash.

Treatment:  gastric lavage followed by the use of activated charcoal.

If necessary, conduct symptomatic therapy.

Special instructions

Irregular use of terbinafine or premature discontinuation of treatment may lead to relapse of the disease. If there is no improvement in the condition after 2 weeks of treatment for a skin infection, it is necessary to re-determine the causative agent of the disease and its sensitivity to the drug.

Systemic use in onychomycosis is justified only in the case of damage to most nails, the presence of pronounced subungual hyperkeratosis, and the ineffectiveness of previous local therapy. In the treatment of onychomycosis, a laboratory-confirmed clinical response is usually observed several months after mycological treatment and discontinuation of treatment, due to the rate of regrowth of a healthy nail. Removal of nail plates in the treatment of onychomycosis of the hands for 3 weeks and onychomycosis of the feet for 6 weeks is not required.

In the presence of liver disease, the clearance of terbinafine may be reduced. During treatment, it is necessary to monitor the activity of “hepatic” transaminases in the blood serum.

In rare cases, cholestasis and hepatitis occur after 3 months of treatment. If signs of impaired liver function appear (weakness, persistent nausea, decreased appetite, excessive abdominal pain, jaundice, dark urine or discolored feces), the drug should be discontinued.

Prescribing terbinafine to patients with psoriasis requires caution, because in very rare cases, terbinafine can provoke an exacerbation of psoriasis. When treating with terbinafine, general hygiene rules should be observed to prevent the possibility of re-infection through underwear and shoes. During the course of treatment (after 2 weeks) and at the end of it, it is necessary to perform antifungal treatment of shoes, socks and stockings.

Form of production

Tablets

Storage conditions

At a temperature not exceeding 25 °C

Shelf life

3 years

Active ingredient

Terbinafine

Conditions of release from pharmacies

By prescription

Dosage form

Tablets

Purpose

For adults, Children over 12 years of age, Pregnant women as prescribed by a doctor

Indications

Prevention of fungal diseases, Fungus, Skin Fungus