Terbinafin-ratiopharm

Terbinafine ratiopharm is an allylamine derivative with a wide range of antimycotic effects. The medication must be taken orally.

When administered in low concentrations, the drug demonstrates fungicidal activity against yeast fungi, dermatophytes, as well as individual dimorphic fungi. The effect on yeast fungi is fungistatic or fungicidal (determined by the type of fungus). [1]

The drug specifically slows down the early phase of sterol biosynthesis inside the fungal cell. [2]

Indications Terbinafin-ratiopharm

It is used for onychomycosis , provoked by the influence of dermatophytes.

In addition, it is prescribed in the case of dermatomycosis (affecting the feet, trunk, legs and skin under the scalp) and epidermal infections associated with candida fungi (in situations where the location of the lesion, its prevalence or detectability make it advisable to conduct oral treatment).

Release form

The release of the drug is sold in tablets with a volume of 0.25 g - 14 pieces inside a blister pack; in a box - 1 or 2 such packages.

Pharmacodynamics

Terbinafine has a therapeutic effect by inhibiting squalene epoxidase inside the cell wall of the fungus. As a result, there is a lack of ergosterol, and squalene begins to accumulate inside the cells, as a result of which the death of the fungal cell occurs. The squalene epoxidase enzyme is not included in the structure of the hemoprotein P450, which is why terbinafine does not affect the metabolic processes of hormones or other medications.

Terbinafine has been shown to act against dermatophytes from the genus Trichophyton, microsporum, epidermophyton and the yeast-like fungi Candida (mainly against Candida albicans). [3]

Pharmacokinetics

After a single use of 0.25 g of terbinafine, the plasma level Cmax is determined approximately after 2 hours and is equal to 0.97 μg / ml. Intraplasmic synthesis with protein is 99%.

The drug rapidly accumulates inside the keratinized lipophilic skin layer. The drug is also secreted into the sebum, forming high levels inside the nails and hair follicles. During the first few weeks of therapy, the active element accumulates inside the epidermis and nails in concentrations that lead to the development of a fungicidal effect.

The drug is involved in intrahepatic metabolism; most of the inactive metabolic components (71%) are excreted in the urine, and the remainder (22%) is excreted in feces. The half-life is 11-17 hours. Cumulation does not develop inside the body.

Terbinafine is secreted in breast milk.

In individuals with liver / kidney problems, the rate of excretion of the drug may be reduced.

Dosing and administration

Persons over the age of 12, as well as adults, need to use 0.25 g of drugs (1 tablet) once a day.

With onychomycosis, the duration of the course is 1.5-3 months and depends on the duration of the period of regrowth of the nail plate. Sometimes, if the nail grows slowly, the treatment cycle can be longer. The size of the treatment period may also depend on other factors - the conduct of the concomitant treatment course, the patient's age and the condition of the nails at the time of initiation of therapy. The clinical effect often develops after several months from the moment of mycological cure and the completion of the treatment course, which is due to the fact that a healthy nail grows back.

Fungal infections affecting smooth skin: the duration of therapy in the case of mycoses on the feet is 0.5-1.5 months, and in the case of mycoses in other areas of the skin (shins, trunk) - 0.5-1 months. With mycosis of the skin under the scalp, therapy lasts 1 month (but in cases where the causative agent of infection is M. Canis, it can be longer).

Use in persons with liver problems.

Because no studies have been conducted on the use of terbinafine in persons with hepatic lesions in the active or chronic phase, it is prescribed to this group only in situations where the positive effect is more expected than the possible risks.

Prescribing to persons with renal function disorders.

People with similar problems (CC <50 ml per minute or serum creatinine> 300 μmol / L) need to use half a standard dose of 0.5 0.25 g tablets (0.125 g terbinafine), 1 time per day.

• Application for children

There is no information regarding the oral use of drugs (0.25 g tablets) in pediatrics (under 12 years of age), which is why it is not prescribed to the indicated age group, except in situations where the benefits of taking it are more likely than the risks of negative consequences. The duration of therapy and the size of the serving are determined by the weight of the child (for example, if the weight is in the range of 20-40 kg, half of the adult serving is required).

Use Terbinafin-ratiopharm during pregnancy

Because there is no information regarding the safety of using Terbinafina-ratiopharm during pregnancy, it is prescribed only in situations where the likelihood of benefit is higher than the risks of complications.

Because terbinafine is excreted in human milk, it should not be used with breastfeeding.

Contraindications

It is contraindicated to use in case of severe intolerance to terbinafine hydrochloride or other elements of the medication.

Side effects Terbinafin-ratiopharm

The main side signs:

• symptoms of intolerance: urticaria and anaphylactic signs (nausea, low blood pressure, dyspnoea and dizziness), epidermal manifestations (for example, TEN or SJS), photosensitivity and Quincke's edema may be noted;
• lesions associated with the gastrointestinal tract: bloating, heartburn, vomiting, stomach heaviness and taste disturbances (up to its temporary loss);
• hepatic disorders: hepatitis, impaired hepatobiliary function, increased values of intrahepatic enzymes and jaundice;
• problems with hematopoietic activity: thrombocytopenia or neutropenia and agranulocytosis;
• disturbances in the work of the NS: paresthesias, headaches, severe fatigue and sensitivity disorders. Depression or fear is singularly noted;
• other negative symptoms: myalgia, psoriasis, arthralgia, alopecia and menstrual irregularities.

Overdose

In case of poisoning, vomiting, dizziness, pain in the epigastric zone, nausea and headaches are noted.

Gastric lavage is performed, activated carbon is applied, and symptomatic actions are performed.

Interactions with other drugs

Terbinafine has a powerful inhibitory effect on the CYP2D6 enzyme, which must be taken into account when using Terbinafine-ratiopharm in combination with medications whose metabolism is developed by the CYP2D6 enzyme.

Thus, in cases where the patient is using antidepressants (MAOI-B, tricyclics and SIONZS) or β-blockers, terbinafine should be used with extreme caution. A dosage change may be necessary.

Terbinafine differs from antimycotics of the azole type in that it has practically no effect on the ability to increase or slow down the clearance of drugs, the metabolism of which occurs with the participation of hemoprotein P450 (for example, tolbutamide with cycloserine and oral contraception). At the same time, the rate of clearance of terbinafine may increase with the introduction of drugs that increase the metabolic rate (among them rifampicin). At the same time, substances that slow down the activity of hemoprotein P450 (for example, cimetidine) also inhibit the metabolic processes of terbinafine. If you need to combine these medicines, you may need to change the dose of terbinafine.

Storage conditions

Terbinafin-Ratiopharm must be kept out of the reach of small children. Temperature values - maximum 25 ° С.

Shelf life

Terbinafine-Ratiopharm can be used within 36 months from the date of manufacture of the pharmaceutical element.

Analogs

Analogues of drugs are Lamisil, Terbizil with Lamikon, Fungotek and Mykofin with Lamifen.