Terbinafin-Vertex, tablets 250 mg 30 pcs

Terbinafine belongs to the group of allilamines, has a broad spectrum of antifungal action. In low concentrations it has fungicidal effect on dermatophytes Trychophyton spp. (T. rubrum, T. mentagrophytes, T. tonsurans, T.verrucosum, T.violaceum), Microsporum canis, Epidermophyton floccosum, mold fungi (e.g. Scopulariopsis brevicaulis), yeasts, mainly Candida albicans.

It has fungicidal or fungistatic effect on Candida spp. fungi and their mycelial forms depending on a fungus species.

Terbinafine disrupts an early stage of biosynthesis of the main component of the cell membrane of fungus ergosterol by inhibiting the enzyme squalene epoxidase.

When administered orally it is not effective in treating discolorous lichen caused by Pityrosporum ovale, Pityrosporum orbiculare, Malassezia furfur.

Pharmacokinetics

When administered orally it is well absorbed by more than 70%, absolute bioavailability due to the “first pass” effect is approximately 50%. After a single oral administration in a dose of 250 mg time of maximum concentration in plasma (ÒÑmax) is about 1.5 h; maximum concentration (Ñmax) is 1.3 µg/ml.

Area under curve “Concentration – time” (AUC) – 4.56 µh×m/ml, in concurrent usage with food AUC is increased by 20%. With prolonged use Cmax increases by 25%, AUC – 2.3 times. Effective elimination half-life (T1/2) is about 30 hours, terminal T1/2 – 200-400 hours (indicates prolonged excretion from the skin and adipose tissue).

Equilibrium concentration (Css) is independent of age. The plasma concentration of terbinafine is independent of sex. Binding with plasma proteins is more than 99%. Rapidly distributed in tissues, penetrates into dermal layer of skin and nail plates.

It penetrates into the secretion of sebaceous glands and accumulates in high concentrations in hair follicles, in the hair, skin and subcutaneous tissue. It is subject to significant metabolism; the resulting metabolites have no antifungal activity. 70% is excreted by kidneys.

It does not accumulate in the body. The age of patients does not affect the pharmacokinetics of terbinafine, but elimination may be reduced with liver and kidney damage, leading to high concentrations of terbinafine in the blood.
Excreted with breast milk.

Indications

Active ingredient

Composition

How to take, the dosage

Adults:

Internal, after meals. Normal dose: 250 mg once a day.

Children over 3 years of age:

In case of body weight from 20 to 40 kg – 125 mg 1 time per day.

In case of body weight over 40 kg – 250 mg once a day.

The duration of the course of treatment and the dosing regimen are determined on an individual basis and depend on the localization of the process and the severity of the disease.

Onychomycosis: the average duration of therapy is 6-12 weeks. If the nails of the fingers and toes are affected (except for the big toe), or if the patient is young, the treatment duration may be less than 12 weeks. For big toe infections, a 3-month course of treatment is usually sufficient.

Some patients who have a reduced growth rate of the nails may require a longer period of treatment.

Fungal skin infections: duration of treatment in case of interfinger, plantar or “toe” localization of infection is 2-6 weeks; in mycosis of other body areas: shins – 2-4 weeks, trunk – 2-4 weeks; in mycosis caused by fungi of genus Candida – 2-4 weeks; in mycosis of scalp caused by fungi of genus Microsporum – more than 4 weeks.

The duration of treatment of mycoses of the scalp is about 4 weeks; if infected with Microsporum canis, it may be longer.

Elderly patients are prescribed the drug in the same doses as adults.

Patients with hepatic or renal insufficiency take 125 mg once a day.

Interaction

Inhibits CYP2D6 isoenzyme and impairs metabolism of drugs such as tricyclic antidepressants and selective serotonin reuptake inhibitors (e.g., desipramine, fluvoxamine), Beta-adrenoblockers (metoprolol, propranolol), antiarrhythmic drugs (flecainide, propafenone), monoamine oxidase B inhibitors (e.g., selegiline) and antipsychotics (e.g., chlorpromazine, haloperidol).

The drugs inducers of cytochrome P450 isoenzymes (e.g., rifampicin) may accelerate the metabolism and excretion of terbinafine from the body. Medicinal products – cytochrome P450 isoenzyme inhibitors (e.g., cimetidine) may slow down the metabolism and excretion of terbinafine from the body. With the simultaneous use of these preparations it may be necessary to adjust the dose of terbinafine.

Menstrual cycle disorders may occur when terbinafine and oral contraceptives are used at the same time.
Terbinafine reduces caffeine clearance by 21% and prolongs its half-life by 31%. It does not affect the clearance of phenazone, digoxin, warfarin.

When co-administered with ethanol or drugs with hepatotoxic effects, there is a risk of drug-induced liver damage.

Special Instructions

If used irregularly or ended early, treatment increases the risk of relapse.

The duration of therapy may also be affected by factors such as the presence of comorbidities and the condition of the onychomycosis nails at the start of treatment.

If we have not seen improvement after 2 weeks of treatment for a skin infection, the causative agent and its sensitivity to the drug must be determined again.

The systemic use in onychomycosis is justified only in case of total lesion of the majority of nails, the presence of marked subnail hyperkeratosis, the failure of previous local therapy.

In the treatment of onychomycosis, a clinical response, confirmed by laboratory tests, is usually observed several months after mycological cure and discontinuation of the treatment, due to the rate of growth of healthy nails.

Nail plate removal is not required for treatment of hand onychomycosis for 3 weeks and foot onychomycosis for 6 weeks.

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

In rare cases after 3 months of treatment cholestasis and hepatitis occur. If signs of liver dysfunction occur (weakness, persistent nausea, decreased appetite, excessive abdominal pain, jaundice, darkened urine or discolored stools) the drug should be stopped.

Prescribing terbinafine to patients with psoriasis requires caution because in very rare cases terbinafine may provoke an exacerbation of psoriasis.

In treatment with terbinafine, general rules of hygiene should be followed to prevent the possibility of reinfection through underwear and shoes. During treatment (after 2 weeks) and at the end of treatment, antifungal treatment of shoes, socks and stockings should be performed.

Influence on the ability to drive and operate machinery

There are no data on the effect of Terbinafine on the ability to drive vehicles and mechanisms.

Contraindications

Side effects

Overdose

Pregnancy use

Similarities