Terbinafine

Terbinafine is an antimycotic drug with fungicidal activity. It has an effect on most types of fungi that can infect the human body.

In small concentrations, the drug has a fungicidal effect on the activity of dermatophytes with mold fungi, as well as individual types of dimorphic fungi. In relation to yeast fungi, it can have not only a fungicidal, but also a fungistatic effect.

Indications Terbinafina

All forms of the drug can be used for diseases whose development was caused by the action of mold and yeast-like fungi, as well as dermatophytes.

The tablets are used for pathologies of fungal genesis and provoked by the activity of dermatophytes such as trichophyton (T. Mentagrophytes, T. Violaceum, as well as red trichophyton, T. verrucosum and crateriform trichophyton), downy microsporum and flocculent epidermophyton, as well as candida fungi. The medication in tablets is used for microsporia, epidermophytosis, trichophytosis with onychomycosis and candidiasis.

Tablets are often used in cases of intense and widespread manifestations. Using tablets for the versicolor form of lichen will be ineffective.

The cream is usually prescribed for fungal pathologies caused by the action of Candida, Trichophyton, Microsporum pubescens, Epidermophyton flocculens and Pityriasis fungi.

Along with this, the cream and ointment can be used for epidermal lesions caused by the influence of dermatophytes, candidiasis and pityriasis versicolor.

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Release form

The drug is produced in tablets of 0.25 g; a pack may contain 7 or 10 tablets. In addition, it is sold in the following forms: 1% cream for external treatment, spray and ointment.

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Pharmacodynamics

The medicinal effect of the drug develops through a destructive effect on the walls of fungal cells, and in addition to this, through a specific slowdown in the activity of squalene epoxidase (this enzyme is extremely important for the normal functioning of the fungal cell wall).

The effect of Terbinafine helps to stop the production of ergosterol, the deficiency of which inside the fungal cell leads to an increase in the volume of squalene. As a result, all enzyme systems are inactivated and the cell dies.

The active substance of the drug does not affect the hemoprotein P450 system, therefore it does not affect the metabolic processes of hormones or other drugs.

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Pharmacokinetics

After taking the drug orally, it is rapidly absorbed from the gastrointestinal tract. Some of the metabolic processes of the drug occur in the liver, so its bioavailability values are reduced to 40%. Eating food has an insignificant effect on bioavailability indicators, so there is no need to adjust the portion.

Blood values of Cmax are noted after 120 minutes from the moment of taking a portion of 0.25 g of the substance. The drug is 99% synthesized with intraplasmic protein.

The drug indicators that are optimal for the development of medicinal effects are observed inside the epidermis with the subcutaneous layer, hair and nails.

In the body, terbinafine hydrochloride is converted into metabolic elements that do not have an antimycotic effect. Most of them are excreted in the urine. The half-life is 17 hours.

The medicine taken does not accumulate.

If the patient has kidney or liver disease, the conversion of the drug may slow down. As a result, its indicators in biological fluids increase and the period of circulation of the substance in the blood is prolonged.

When the medicine is used locally, a maximum of 5% of the active element penetrates into the blood.

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Dosing and administration

Schemes for using the medication tablets.

The duration of taking the tablets is selected by the attending physician, taking into account the severity of the disease. Children should take the medication after eating, once a day. When selecting a single dosage, the child's weight should also be taken into account.

Children weighing less than 20 kg are required to take 62.5 mg of the substance; children weighing 20-40 kg – 125 mg; children weighing over 40 kg – 0.25 g.

Adults should take 0.25 g of the substance once a day or 125 mg twice a day.

The duration of the therapeutic cycle is determined by the type of disease. In the case of dermatomycosis affecting the feet, the tablets are taken for 0.5-1.5 months.

In case of dermatomycosis infecting the trunk, limbs or shins, as well as epidermal candidiasis, therapy continues for 0.5-1 month.

In case of infections affecting the scalp, therapy lasts 1 month.

During onychomycosis, treatment should continue for 1.5-3 months. Sometimes, if the patient's nails grow too slowly, the therapy may be longer. The therapeutic effect is observed even after several months from the end of the treatment cycle.

Methods of using medicinal ointment.

The infected areas should be treated with cream or ointment 1-2 times per day. Before using the medicine, the affected epidermis should be cleaned and dried. The treatment is carried out in a thin layer - in addition to the infected areas, the substance is applied, rubbing in a little, to nearby areas. If diaper rash appears against the background of the infection, these areas can be covered with gauze after treatment with Terbinafine. It is recommended to do this when applying the medicine at night.

The duration of the therapeutic course depends on the type of disease.

In case of dermatomycosis in the area of the trunk, limbs or shins, as well as candidiasis affecting the epidermis, the medication is applied for a period of 7-14 days.

During pityriasis versicolor - 14 days.

For dermatomycosis in the foot area – 0.5-1 month.

In case of nail mycosis, the medication is used for a period of 3-6 months.

Usually, clinical symptoms are relieved after the first few days of drug use. It is necessary to take into account that in case of irregular use or premature discontinuation of treatment, a relapse of the infection may occur.

If after 14 days of continuous use of the cream the signs of pathology do not subside, it is necessary to consult a doctor and verify the diagnosis.

The spray should be applied externally – 1-2 times a day.

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Use Terbinafina during pregnancy

During testing, the active component of the drug did not show teratogenic activity. The use of the drug in pregnant women is allowed only in situations where the probable benefit is more expected than the risks of complications for the fetus.

Since the active substance is excreted in milk, breastfeeding should be discontinued during therapy.

Contraindications

The main contraindications for tablets:

• liver diseases of an active or chronic nature;
• chronic renal failure (CC values below 50 ml per minute);
• hypolactasia, lactase deficiency, and glucose-galactose malabsorption;
• severe intolerance to the components of the drug.

Use the tablets with caution in the following conditions:

• CRF (CrF values over 50 ml per minute when performing the Reberg test);
• hematopoietic disorders;
• alcoholism;
• endocrine pathologies;
• psoriasis;
• tumors;
• vascular constriction in the extremities;
• SLE or cutaneous lupus.

During the use of Terbinafine, it is necessary to closely monitor the functioning of the kidneys and liver. It is necessary to stop taking the tablets if the following symptoms develop:

• nausea, abdominal pain, loss of appetite;
• feeling of weakness;
• jaundice or darkening of the urine;
• light colored feces.

Local forms of the drug are not prescribed for symptoms of allergy and severe intolerance.

Caution in using the cream or ointment is required in the following disorders:

• tumors;
• liver or kidney failure;
• endocrine pathologies;
• alcoholism;
• disorders of hematopoiesis;
• narrowing of the vascular lumen.

Side effects Terbinafina

Side effects when taking the tablets include:

• loss of appetite, weakness and pain in the epigastric region, diarrhea, taste disorders, nausea;
• cholestasis;
• signs of allergy;
• decrease in blood levels of neutrophils and platelets.

After local treatment with ointment or cream, hyperemia, burning or itching may occur in the areas of application. Occasionally, allergy symptoms may appear.

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Overdose

In case of poisoning with Terbinafine tablets, the patient may experience rashes, headaches, nausea, dizziness, increased urination, vomiting and pain in the epigastric region.

Gastric lavage should be performed and the patient given activated charcoal; symptomatic measures are taken.

If a patient accidentally takes the medicinal cream orally, he may experience dizziness, nausea, pain in the epigastric region and headaches.

In this case, symptomatic procedures are performed and activated charcoal is prescribed.

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Interactions with other drugs

Terbinafine use may affect clearance rates of drugs whose metabolism occurs via the P450 hemoprotein system. These include cyclosporine with tolbutamide and oral contraception.

The drug increases plasma levels of H2-histamine blockers.

The drug inhibits the excretion of rifampicin, and the latter at the same time doubles the clearance rates of Terbinafine.

Women using oral contraception may experience menstrual cycle irregularities.

The drug slows down the activity of the isoenzyme CYP2P6, which disrupts the metabolism of SSRIs, tricyclics with antiarrhythmic drugs, as well as β-blockers, antipsychotics and MAOI type B.

The drug's effect results in a 21% decrease in the clearance rate of caffeine, while its half-life increases by 31%.

The drug does not affect the clearance rates of warfarin with digoxin and phenazone.

Combination with medications that have hepatotoxic properties or ethyl alcohol increases the risk of drug-induced liver damage.

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Storage conditions

Terbinafine should be stored in a place closed to small children. Temperature values - not higher than 25°C.

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Shelf life

Terbinafine is approved for use for a period of 2 years from the date of manufacture of the drug.

Application for children

LS tablets are not used in children under 3 years of age weighing less than 20 kg. Also, when using them, you should carefully follow the prescribed portion.

Local forms of the medication are prescribed to children over 12 years of age.

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Analogues

Analogues of the tablet form of the drug are Exifin, Lamikan, Binafin with Onikhon, as well as Mikonorm, Terbisil, Terbinafine hydrochloride, etc.

Analogues of drugs for external treatment are Terbinoks, Lamitel with Termicon, Mikonorm with Lamisil Uno, Terbinafine-MFF, Terbizil, etc.

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Reviews

Terbinafine tablets generally receive good reviews on forums. They help eliminate fungal infections and restore damaged nail structure.

Comments on the ointment and cream are also quite good. They note high efficiency (fungi and diaper rash are completely eliminated in a few weeks of therapy), as well as a fairly low price for the drug. Among the advantages, they also highlight the rare occurrence of side effects.

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