Antimycotics for the treatment of onychomycosis

There are no pathogenic fungi in the natural microflora of humans and animals. Fungi are eukaryotes that do not have chlorophyll and cannot photosynthesize. Most fungi are saprophytes (heterotrophs) of the environment and need to be fed ready-made organic matter. The body of the mushroom is represented by a micelle - a network of thin branched tubular fibers called hyphae. Fungi reproduce by spores. During accidental inoculation, fungi can cause various diseases of the skin, mucous membranes and internal organs of sensitive tissues, in suitable nutrient substrates. Fungal diseases are called mycosis (from the Greek. Mykes - fungus).

healthy and fungal nail

The causative agents of mycoses are parasitic microscopic fungi of the genus: Arthroderma, Aspergillus, Amanita, Microsporum, Penicillium, Candida, Saccharomyces, Trichophyton, Epidermophyton, etc. , muscles, bones, internal organs and nervous system. Actinomycosis is a serious disease caused by bright fungi of actinomycetes, blastomycosis is a deep mycosis of the skin, the causative agent is a pathogenic dimorphic fungus. Other diseases include deep (visceral) mycoses. Superficial mycoses affect the stratum corneum, scalp, nail plates, and mucous membranes.

The most common keratomycosis affecting only the stratum corneum; Dermatomycoses affect smooth skin, epidermis and its appendages: hair, nails.

According to the type of pathogenic fungus and the localization of the pathological process, they are:

  • epidermophytosis - mycoses of the skin of the groin folds, lower leg, interdigital wrinkles, brushes;
  • trichomycosis (from the Greek trichos - hair) - damage to the scalp, velvety hairs on the body;
  • trichophytosis (ringworm), microsporia, favus (scab);
  • onychomycosis (Greek onychos - nail) - damage to the nail plates on the hands or feet by dermatophytes (less mold or yeast).

Antifungal drugs are used for diseases caused by various types of pathogens or opportunistic fungi. According to the localization of pathogenic fungi, antifungal drugs are classified as drugs for treatment:

  • systemic mycoses;
  • candidiasis;
  • superficial mycoses.

The chemical classification of antifungal drugs is divided into:

antibiotics:

  • polyene antibiotics (amphotericin B, amphoglucamine, natamycin, nystatin);
  • non-polyene antibiotics (griseofulvin);

synthetic drugs:

  • imidazole derivatives (bifonazole, isoconazole, ketoconazole, clotrimazole, miconazole, oxyconazole, omoconazole, sertaconazole);
  • triazole derivatives (itraconazole, fluconazole, thermoconazole, thioconazole);
  • allylamine derivatives (terbinafine, naftifine);
  • morpholine derivatives (amorolfine);
  • Derivatives of different chemical groups: undesylene acid cyclopirox, flucytosine, potassium iodide, etc.

Onychomycosis

Onychomycosis is caused by an infection of the nail plate. Most infections occur in public baths, saunas and swimming pools. Scales containing spores and fungal mycelium in patients with onychomycosis fall to the floor, benches, cages, paths, carpets and bedding. Under conditions of high humidity, fungi can not only last a long time (years), but also multiply, which makes them a strong source of infection. A person who moves barefoot on the floor or touches household items with such scales can be infected because they stick to the skin and are corrected. The infection develops after the fungus penetrates the nail structures. In the future, they begin to activate, multiply and form tunnels and passages. When exposed, nails thicken, break, turn yellow and break. Sometimes the process also affects the skin, which is accompanied by itching and scaly rashes in the interstitial area. Such diseases are distinguished by a long and lasting way.

Probability of susceptibility to infection, vegetative-vascular pathology, diabetes, peripheral circulatory disorders, osteoarthropathy of the legs, etc. increases with age, especially in those over 65 years of age due to the presence of chronic diseases such as changes in. nail plates.

Treatment of onychomycosis is carried out according to a certain scheme for a long time - from 2 to 4 months. Therapy uses antifungals that have fungistatic and fungicidal effects and affect the various exchanges and metabolism of the vital activity of pathogens. As a result, there are three main mechanisms of antifungal action of antifungal drugs:

  • disruption of the structure and function of the cell wall of fungi (imidazoles, triazoles);
  • disruption of mitosis of eukaryotic cells by inhibiting the synthesis of nucleic acids (grizeofulvin);
  • Inhibition of transmembrane exchange processes through the cell membrane (cyclopirox) of fungi.

Medications of choice

Griseofulvin(Griseofulvinum) mark. 125 mg, an antibiotic produced by the Penicillium nigricans (griseofulvum) mold, was isolated in 1939 and is a spiro derivative of benzofuran. The drug has fungistatic properties against all types of fungi - trichophytes and epidermophytes. The mechanism of the fungistatic effect is based on the ability of the drug to inhibit the division of filamentous fungi in the metaphase into cells and cause characteristic morphological changes (torsion, branching and curvature of the hips), disrupting the synthesis of the mitotic shaft and cell wall. The drug inhibits the synthesis and polymerization of small amounts of nucleic acids. The drug has no antibacterial effect.

Long-term treatment is required to create sufficient concentration on the skin - 2-3 months. Only new, old nails will show the first signs of the effectiveness of the treatment.

It is important! Side effects while taking the drug include: dyspeptic disorders, dizziness, sometimes insomnia, allergic reactions, leukopenia. Griseofulvin is contraindicated in hematopoiesis, suffocation of liver and kidney failure, as well as in infants and pregnant women. You should not prescribe the drug to transport drivers, people working at high altitudes or those who require more attention, rapid mental and motor reactions. Patients should be warned about the development of cross-sensitivity to penicillin and the increased effects of alcohol.

Ketoconazole(Ketoconazole) - an active broad-spectrum drug from the group of imidazole with fungicidal and fungistatic activity; It is effective orally with systemic and superficial mycosis, dermatomycosis and candidiasis. It is prescribed by a doctor for the treatment and prevention of fungal infections caused by drug-sensitive pathogens on the hair, nails, genitals.

When administered orally, the drug is well absorbed, dissolved and absorbed in an acidic environment.

It is important! The drug is well tolerated by patients, but can cause dyspeptic symptoms (nausea, vomiting, diarrhea), very rarely allergic reactions in the form of urticaria and skin rash, headache, dizziness, gynecomastia, impotence. Concomitant use of the drug with other drugs (fentanyl, tamsulosin, carbamazepine, salmeterol, etc. ) may increase the concentration of the latter with an increase in side effects.

Contraindicated in severe liver, kidney, pregnancy, breastfeeding and hypersensitivity to the drug.

Ketoconazole is available in the table. 200 mg suppository. 400 mg; 2% ointment, 15 mg; cream 20 mq / q - 15 gr. Used in the form of shampoo. The duration of treatment is determined individually.

Itraconazole(Itraconazole) caps. 100 mg; solution 10 mg / ml - vial150 ml - the drug has a broad spectrum of action, selectively and specifically inhibits the enzyme that catalyzes the synthesis of fungal sterols. Scope: various infections caused by dermatophytes and / or yeast and mold fungi, such as candidiasis of the mucous membrane (including the vagina), skin mycoses, onychomycosis, epidermomycosis, fungal lesions of the eyes (keratitis), peritoneum and other localizations. Taking itraconazole capsules immediately after a meal increases its bioavailability; Maximum concentration in blood plasma is reached within 3-4 hours. after admission. The drug is well distributed in tissues susceptible to fungal infections.

It is important! Side effects from the digestive system may occur when using the drug: dyspepsia (nausea, vomiting, diarrhea, constipation, loss of appetite), abdominal pain, loss of taste; headache, dizziness, allergic reactions, alopecia, hematopoietic organs (rarely) - leukopenia, thrombocytopenia. It is contraindicated in case of hypersensitivity to itraconazole and any part of the drug, children under 3 years of age, pregnancy and lactation.

For optimal absorption of the drug, the capsules should be taken without chewing and swallowed immediately after a meal. One course of pulse therapy for onychomycosis consists of taking 2 valves daily. medication twice a day for a week. Two courses are recommended for the treatment of fungal infections of the nail plates of the hands. Three courses are recommended for the treatment of fungal infections of the toenails. The interval between courses where you do not need to take medication is 3 weeks.

Terbinafine(Terbinafine) - is produced in the form: target. 250 mq; % 1 ointment 15. 0 g; % 1 cream - 10, 15, 30 g tube; % 1 spray, 20 ml. The drug is called allylamines and is prescribed for systemic and external use. The mechanism of action of terbinafine is associated with inhibition of the initial stage of biosynthesis of ergosterol (the main cellular sterol of the fungal membrane) by inhibiting the specific enzyme scalene-2, 3-epoxidase in the fungal membrane. The drug is effective against many fungi that are pathogenic to humans. Terbinafine with topical treatment is more effective than azole drugs, imidazole derivatives, but can be compared with itraconazole and is more effective than griseofulvin and itraconazole when administered orally. Terbinafine is characterized by lipoidophilia, rapidly spreads to the epidermis, dermis, subcutaneous tissue, accumulates in sebaceous glands, hair follicles and nail plates in concentrations that have a fungicidal effect. 1 badge. Terbinafine once a day leads to higher treatment rates than intermediate intraconazole therapy and better results for each criterion of effectiveness (including mycological treatment).

Naftifin(Naftifine) cream 1% - 15, 30 g; 10, 20, 30 ml of 1% solution is a derivative of allylamines. The mechanism of action is associated with inhibition of the activity of the enzyme squalene-2, 3-epoxidase, inhibition of the biosynthesis of ergosterols, which leads to disruption of cell wall synthesis. Naftifine has a wide spectrum of fungicidal action against dermatophytes (such as Trichophyton, Epidermophyton, Microsporum), mold (Aspergillus spp. ), Yeast-like fungi (Candida spp. , Pityrosporum) and other fungi (Sphenor scorotricho). . . . The drug has anti-inflammatory effect, reduces itching. When applied externally, it penetrates well into the skin and creates stable antifungal concentrations in various layers.

The duration of treatment with naftif varies from 2 weeks to 6 months. When using the drug, dryness and redness of the skin, burning sensation may occur, all these side effects are reversible and do not need to be eliminated.

Amorolfine(Amorolfine) nail polish% 5 - 2. 5 and 5 ml, - preparation for external use, has a broad spectrum of fungicidal and fungicidal action due to damage to the cytoplasmic membrane of the fungus by disrupting sterol biosynthesis. amount of enzymes 14– gamma demethylase and 7 gamma isomerase. The drug is active against both the most common and rare pathogens of fungal infections of the nails of dermatophytes: Trichophyton spp. , Microsporum spp. , Epidermophyton spp. ; templates: Alternaria spp. , Scopulariopsis spp. , Hendersonula sppi. Fungi of the family Dematiaceae: Cladopsorium spp. , Fonsecaea spp. , Wangiella spp. ; dimorphic fungi Coccidioides spp. , Histoplasma spp. , Sporothrix spp.

When applied to the nails, the drug penetrates almost completely into the nail cavity and further into the nail bed for the first 24 hours. The effective concentration remains on the affected nail plate for 7-10 days. after the first application. Systemic absorption is insignificant. Applied from abroad. The drug is applied to damaged fingers or nails 1-2 times a week. The duration of treatment is determined individually and depends on the indications for use. Side effects are rare and appear in the form of itching, burning at the site of application. Not intended for young children and infants.

Dekesilen acidand salts - antifungal drugs for external use, which have a fungistatic and fungicidal effect against dermatophytes, when combined with zinc or copper salts - zinc undesilenat or copper undesilenat - increase activity. Zinc, which is an integral part of the drug, has an astringent effect, reduces the appearance of signs of skin irritation and promotes faster healing.

  • Undesylene acid + zinc undecilenate (TN, ointment 30 g tube, 25 g ointment in bottles);
  • Undekilen acid + Copper undesilenat + HCV glycerol - used to treat and prevent fungal skin diseases caused by drug-sensitive fungi (dermatophytes).

The drugs are applied to a clean, dry surface of the affected skin twice a day (morning and evening). The duration of treatment is 4-6 weeks and depends on the nature, effectiveness and course of the disease. They continue to be used once a day after the disappearance of clinical symptoms of the disease. For prophylactic purposes - 2 times a week.

It is important! Contraindications to the use of the drug are hypersensitivity to undecylenic acid and its derivatives.

Cyclopirox(Ciclopirox) nail polish% 8, fl. 3 g is a broad-spectrum antifungal drug that prevents the retention of precursors for the synthesis of macromolecules in the cell membrane. It is used externally for the treatment and prevention of fungal infections of the skin, mucous membranes, nails, fungal vaginitis and vulvovaginitis.

The drug is applied to the affected nail 1-2 times a day, the duration of use depends on the severity of the lesion, but should not exceed 6 months.

Treatment of onychomycosis should be carried out under the strict supervision of a dermatologist. As a rule, a rational etiotropic complex therapy is used. Reduction or disappearance of clinical symptoms is usually observed a few days after taking antifungals. However, the course of treatment should be carried out completely to prevent recurrence of the disease. Against the background of clinical treatment, anti-relapse therapy is often used to prevent re-infection.