Pharmacological properties
Bifonazole is a broad-spectrum antifungal agent with activity against dermatophytes, yeasts, molds and other fungi such as Malassezia furfur; in addition, it is active against Corynebacterium minutissimum.
On dermatophytes, bifonazole has, first of all, a fungicidal effect, which begins at a concentration of 5 mg/l 6 hours after application. In addition, bifonazole inhibits the action even at subinhibitory concentrations 2-10 times lower than the MIC. Already at a concentration of 3 ng/ml in the substrate, inhibition of the growth of rapidly proliferating mycelium of Trichophyton mentagrophytes begins.
On yeast fungi, such as the genus Candida, bifonazole has a mainly fungistatic effect, and at a concentration of 20 mg/l - a fungicidal effect.
The fungistatic effect of bifonazole is based on the inhibition of ergosterol synthesis due to inhibition of cytochrome P450-mediated demethylation of trimethylsterols. The lack of ergosterol, which is the main component of the fungal cell membrane, leads to a violation of the permeability of the cell membrane, resulting in the gradual lysis (destruction) of fungal cells.
In addition, bifonazole causes a general slowdown in sterol synthesis as a result of direct inhibition of microsomal HMG-CoA reductase.
The fungicidal effect of the drug is observed simultaneously with the fungistatic effect, which is explained by the sequential effect of suppressing HMG-CoA reductase and at the same time slowing down the synthesis of terpenoids and inhibiting the activity of cytochrome P450.
Bifonazole penetrates well into the affected layers of the skin. 6 hours after application of the drug, its concentrations are determined, corresponding to or many times exceeding the MIC for the main pathogens of dermatomycoses of 1000 μg / cm 3 in the upper layer of the epidermis and up to 5 μg / cm 3 in the papillary layer.
T ½ of bifonazole from the upper and middle layers of the epidermis is approximately 20 hours, from the lower layer - approximately 33 hours.
After topical application to healthy skin, bifonazole 1% solution is absorbed in an amount of 1%. The absorbed amount is excreted as metabolites within 5 days: approximately 45% is excreted in the urine and 39% in the feces.
The long-term retention of effective antifungal concentrations of bifonazole in the skin and the type of its fungicidal action are the main factors in achieving a clinical effect with topical application of the drug once a day.
During the absorption study with topical application to healthy areas of human skin, the concentration of the active substance in the blood plasma was always below the detection limit, and only when applied to affected areas of the skin was it possible to detect insignificant absorption. Due to such a low concentration of the active substance (only 5 ng / ml), the systemic effect of the drug on the body is unlikely.
Indication
Treatment of skin infections caused by dermatophytes, yeasts and molds, as well as other pathogens such as malassezia furfur or corynebacterium minutissimum, for example:
mycoses of the skin and skin folds (Tinea corporis and Tinea inguinalis); interdigital mycoses (Tinea pedis, Tinea manuum); multi-colored (brachny) lichen (Pityriasis versicolor); superficial candidiasis of the skin; erythrasma.
Application
dosage
Unless otherwise prescribed by a doctor, the drug should be applied to the skin once a day. It is better to apply Bifon Skin cutaneous solution in a thin layer or spray it on the affected areas of the skin, rubbing it in, in the evening before going to bed.
In most cases, a few drops of the solution (approximately 3 drops) are sufficient to apply to a palm-sized area of skin and then rub in. When using a spray with a dispenser, 1-2 presses on the spray head are sufficient.
To achieve a long-lasting effect, Bifon Skin should be used even after symptoms have subsided.
In general, the duration of treatment for:
mycosis of the feet, interdigital mycoses (Tinea pedis, Tinea pedis interdigitalis) is 3 weeks; mycoses on other areas of the skin, on the hands and skin folds (Tinea corporis, Tinea manuum, Tinea inguinalis) - 2-3 weeks; multi-colored lichen (Pityriasis versicolor), erythrasma - 2 weeks; superficial candidiasis of the skin - 2-4 weeks.
The course of treatment should be continued until the disappearance of positive results of fungal cultures, but not less than 14 days after the symptoms have subsided. Between the last application of the drug and the sowing of fungal culture, a break of 3-4 days should be made to prevent the possible influence of residues of the active substance on the culture.
Contraindication
Bifon Skin is not used in patients with hypersensitivity to any of the components of the drug.
Bifon Skin, a cutaneous solution, is not used to treat lesions of the ear canal.
Side effects
According to the data obtained, the occurrence of side effects is classified as follows:
very common (1/10); common (1/100 to 1/10); uncommon (1/1000 to 1/100); rare (1/10,000 to 1/1000); very rare (1/10,000); not known (frequency cannot be estimated from the available data).
Temporary effects such as slight redness, burning or skin irritation may often occur.
In case of hypersensitivity to the active substance or any other component of the drug, contact allergic reactions may occur, the manifestations of which are itching, hyperemia, bubbles (vesicles) extending beyond the contact area (so-called rash reactions).
Special instructions
If any adverse reactions occur, the drug should be discontinued.
Use during pregnancy and breastfeeding. There is no experience of using the drug in pregnant women, therefore Bifon Skin should be used only when, in the opinion of the doctor, the expected positive effect for the mother outweighs the potential risk to the fetus. During breastfeeding, Bifon Skin, cutaneous solution, should not be applied to the mammary glands.
Children. The use of Bifon Skin in children is possible only under the supervision of a doctor.
The ability to influence the reaction speed when driving vehicles or working with other mechanisms. Does not affect.
Interactions
Unknown.
Overdose
There have been no reports of overdose.
Storage conditions
At a temperature not exceeding 25 °C. The shelf life after opening the dropper bottle, spray bottle with a dispenser is 8 weeks.
