Metronidazole, Miconazole

Pharmacological properties

Pharmacodynamics

Ginex Forte is a combined antimicrobial drug, the effect of which is due to the metronidazole and miconazole that make up its composition.

Miconazole nitrate is a local antifungal and antibacterial drug with a wide spectrum of action of the imidazole group. Miconazole inhibits ergosterol biosynthesis and alters the lipid composition of the membrane, causing the death of the fungal cell. It has a fungicidal effect on dermatophytes (Trichophyton rubrum, Trichophyton mentagrophytes, Epidermophyton floccosum, Microsporum canis), yeast and yeast-like fungi (Candida albicans, Candida glabrata and other Candida species, Malusillus penis, Malasse penza, Malasse ) Miconazole nitrate has an antibacterial effect, more pronounced against gram-positive bacteria.

Metronidazole, a derivative of 5-nitroimidazole, is an antibacterial and antiprotozoal agent. It is effective against infections caused by anaerobic bacteria and protozoa, including Trichomonas vaginalis, Gardnerella vaginalis and anaerobic streptococci.

Miconazole nitrate and metronidazole do not have synergistic and antagonistic effects.

Pharmacokinetics

Absorption. Miconazole nitrate. The absorption of miconazole nitrate through the walls of the vagina is negligible (about 1.4% of the dose). Miconazole nitrate is not detected in plasma with intravaginal administration.

Metronidazole. The bioavailability of metronidazole with intravaginal administration is 20% compared with its oral bioavailability. The equilibrium concentration of metronidazole in blood plasma is 1.6–7.2 μg / ml after intravaginal administration of a daily dose of the drug.

Distribution. Miconazole nitrate. Binding to plasma proteins is 90–93%. Its penetration into the CSF is low, but it is widely distributed in other tissues. The distribution volume is 1400 liters.

Metronidazole. It is widely distributed in tissues and body fluids, including bile, bone tissue, mammary glands, milk, brain abscesses, CSF, liver and liver abscesses, saliva, seminal fluid and vaginal secretion, and reaches concentrations similar to those observed in blood plasma. Metronidazole crosses the placental barrier and quickly enters the bloodstream of the fetus. Binding to plasma proteins - not more than 20%. The volume of distribution is 0.25–0.85 l / kg.

Metabolism. Miconazole nitrate. Metabolized in the liver. 2 inactive metabolites are determined (2,4-dichlorophenyl-1H-imidazole-ethanol and 2,4-dichloromindaleic acid).

Metronidazole. Metabolized in the liver by oxidation, hydroxymetabolite is active. The main metabolites of metronidazole - hydroxy derivatives and derivatives of acetic acid - are excreted in the urine. The activity of hydroxymetabolite is 30% of the biological activity of metronidazole.

Miconazole nitrate. T_½ is 24 hours. Less than 1% is excreted in urine. About 50%, mainly unchanged, is excreted in the feces.

Metronidazole. T_½ is 6–11 hours. Approximately 6–15% of the dose of metronidazole is excreted in the feces. About 60–80% of metronidazole is excreted unchanged in the urine and as metabolites. Approximately 20% of metronidazole is excreted unchanged in the urine.

Data from preclinical studies. The results of standard preclinical studies of toxicity with repeated use, genotoxicity, carcinogenicity and reproductive toxicity do not indicate the existence of a specific risk to the human body.

In an in vitro microbiological study, there was no synergistic or antagonistic interaction between the active substances that make up the drug, the actions against Candida albicans, Streptococcus (Streptococcus agalactiae according to Lancefield), Gardnerella vaginalis and Trichomonas vaginalis.

Indications

For the treatment of candida vulvovaginitis caused by candida albicans, bacterial vaginosis caused by anaerobic bacteria and gardnerella vaginalis, trichomonas vaginitis caused by trichomonas vaginalis, and mixed vaginal infections.

Application

In adults, apply intravaginally in the evening before bedtime, 1 suppository at night for 7 days.

For relapses of the disease or vaginitis resistant to other treatment, the drug should be used in the evening before bedtime, 1 suppository at night for 14 days.

It is not recommended to use Ginex Forte during menstruation due to a decrease in the effectiveness of the drug and the possibility of some complications during administration.

Vaginal suppositories should be administered in a supine position, deep in the vagina. If possible, do not take an upright position for at least half an hour after the introduction of the suppository. Do not use double doses to compensate for the missed dose.

Contraindications

• Hypersensitivity to any of the active ingredients of the drug or their derivatives; drinking alcohol during treatment or within 3 days after completion of treatment; taking disulfiram during treatment or within 2 weeks after completion of treatment; i trimester of pregnancy; porphyria; epilepsy; severe liver dysfunction.

Side effects

The incidence of systemic side effects is negligible due to the very low level of metronidazole in blood plasma with vaginal administration of the drug (2-12% of the level achieved with oral administration of metronidazole). another active substance of the drug, miconazole nitrate, can cause irritation in the vagina (burning, itching), like all other antifungal agents containing imidazole derivatives that are administered intravaginally (2-6%). with vaginitis, the use of the drug can cause inflammation of the vaginal mucosa. therefore, burning and itching in the vagina can be observed until the third day of therapy. the severity of these symptoms is significantly reduced during treatment. in case of severe irritation or other allergic reactions (rash, angioedema in the face, lips, tongue, larynx and bronchospasm), the use must be stopped.

Adverse reactions due to local action of the active ingredients of the Ginex Forte drug

Metronidazole: hypersensitivity reactions (including rash), abdominal pain, headache, itching, burning and irritation of the vagina.

Miconazole nitrate: vaginal irritation (burning, itching).

Adverse reactions due to the systemic effect of the active ingredients of the Ginex Forte drug

On the part of the blood and lymphatic system: agranulocytosis, neutropenia, thrombocytopenia, pancytopenia, leukopenia.

From the side of the immune system: hypersensitivity reactions, allergic reactions, angioedema, urticaria, fever, anaphylactic shock.

From the side of the psyche: depression, hallucinations, impaired consciousness.

From the nervous system: dizziness, headache, fatigue, weakness, ataxia, cramps, peripheral neuropathy, aseptic meningitis, encephalopathy * (for example, confusion, fever, increased sensitivity to light, torticollis, hallucinations, paralysis, visual impairment and movement), subacute cerebellar syndrome * (for example, ataxia, dysarthria, gait disturbance, nystagmus, tremor).

From the side of the organ of vision: temporary visual impairment, such as diplopia, myopia, blurry image, decreased visual acuity, a change in the perception of colors, optical neuropathy / neuritis.

Hepatobiliary disorders: increased levels of liver enzymes (AsAT, AlAT, ALP), cholestatic or mixed hepatitis and damage to liver cells (hepatocytes), sometimes with jaundice; reported cases of liver failure requiring liver transplantation in patients treated with metronidazole and other antibiotics.

On the part of the skin and subcutaneous tissue: a rash, including one that may be accompanied by fever, flushing, hyperemia, pruritus, polymorphic erythema, Stevens-Johnson syndrome, toxic epidermal necrolysis, contact dermatitis.

From the musculoskeletal system and connective tissue: myalgia, arthralgia.

From the kidneys and urination organs: dark urine (due to the metabolism of metronidazole).

From the gastrointestinal tract: anorexia, taste disturbance, inflammation of the oral mucosa, metallic taste in the mouth, coated tongue, stomatitis, glossitis, nausea, vomiting, constipation, epigastric pain, diarrhea, dry mouth, decreased appetite, abdominal pain and cramping.

General disorders and reactions at the injection site: vaginal discharge, vaginitis, vulvovaginal irritation, discomfort in the pelvic area, thirst, burning sensation in the vagina, itching, irritation, local irritation and sensitivity, hot flashes, fever.

* May disappear after discontinuation of the drug.

special instructions

Alcohol. the patient should be warned that alcohol should not be taken during therapy and for 3 days after completion of the course of treatment, since reactions from the central nervous system similar to disulfiram may occur (see interactions).

Long-term use. High doses of the drug and a long period of use can cause peripheral neuropathy and convulsions.

Simultaneous treatment of sexual partners. The sexual partners of patients with trichomonas vaginitis should also undergo treatment. Sexual partners who have Trichomonas vaginalis detected should undergo treatment at the same time as the patient.

Renal and liver failure. In renal failure, the dose of metronidazole must be reduced.

In severe liver failure, metronidazole clearance may be altered. Metronidazole may increase the symptoms of encephalopathy due to its elevated plasma level. Therefore, metronidazole should be used with caution in patients with hepatic encephalopathy. The daily dose for these patients should be reduced to ¹/₃.

Use in patients of different age groups. For elderly patients (from 65 years old) the recommendations are the same as for the rest of the patients.

The drug is not recommended for use in virgins and patients who have not reached puberty.

Concomitant use with oral anticoagulants. Metronidazole can increase plasma levels of bisulfan, which can lead to significant toxic effects of bisulfan. It is necessary to more often control the level of prothrombin and the international normalized ratio with the simultaneous use of oral anticoagulants during treatment with metronidazole and within 8 days after its cancellation.

Other application features. Do not swallow suppositories or use the drug in any other way.

The suppository base may undesirably interact with rubber or latex, from which contraceptive diaphragms and condoms are made, so their simultaneous use with suppositories is not recommended.

Means for intravaginal use (e.g. tampons, douching or spermicides) should not be used simultaneously with treatment.

In case of severe vaginal irritation (burning, itching), it is necessary to stop treatment with Ginex Forte (see ADVERSE EFFECTS).

Use during pregnancy and lactation

Pregnancy. Pregnancy - Category C.

Since there is insufficient data regarding the lack of negative effects on the fetus and the development of newborns with intravaginal use of suppositories containing metronidazole and miconazole nitrate, women of childbearing age should avoid pregnancy during the use of Ginex Forte.

The use of the drug Ginex Forte in the first trimester of pregnancy is contraindicated.

In the II and III trimester of pregnancy, the drug should only be used as prescribed by the doctor in cases where the expected benefit to the mother outweighs the potential risk to the fetus.

Lactation. During the use of the drug, breast-feeding should be discontinued, as metronidazole passes into breast milk. Breastfeeding can be resumed 1–2 days after the end of treatment.

Fertility. There is no evidence of adverse effects on fertility when metronidazole or miconazole nitrate is used alone.

Children. The drug is not recommended for use in children.

The ability to influence the reaction rate when driving vehicles or working with other mechanisms. Systemic use of metronidazole may affect the ability to drive vehicles or operate machinery. Compared with systemic use, with vaginal administration, the absorption of metronidazole is significantly lower. There is a possibility of dizziness, ataxia, psycho-emotional disorders. In the presence of such symptoms, it is not recommended to drive vehicles or work with mechanisms.

Interactions

Associated with metronidazole (due to absorption)

Alcohol: the interaction of metronidazole with alcohol can cause a reaction similar to that with disulfiram. Do not drink alcohol during therapy and for 3 days after completion of the course (see SPECIAL INSTRUCTIONS).

Amiodarone: increased risk of cardiotoxicity (prolongation of the Q – T interval, flutter and ventricular fibrillation, cardiac arrest).

Astemizole and terfenadine: metronidazole inhibits the metabolism of these drugs and increases their concentration in blood plasma.

Carbamazepine: increases the concentration of carbamazepine in the blood.

Cimetidine: increased levels of metronidazole in the blood and the risk of neurological side effects.

Cyclosporine: increased risk of cyclosporin toxicity.

Disulfiram: CNS effects (e.g. psychotic reactions).

Lithium: increased toxicity of lithium.

Phenytoin: the level of phenytoin in the blood rises, the level of metronidazole in the blood decreases.

Phenobarbital: the level of metronidazole in the blood decreases.

Fluorouracil: increased blood levels and toxicity of fluorouracil.

Oral anticoagulants: the effect of anticoagulants is enhanced, the risk of bleeding increases (see SPECIAL INSTRUCTIONS).

During treatment with the drug, its effect on the blood level of liver enzymes, glucose (hexokinase method), theophylline and procainamide was noted.

Associated with miconazole nitrate (due to the peculiarities of its absorption)

Acenocumarol, anisindione, dicumarol, phenidion, fenprocoumone, warfarin: increased risk of bleeding.

Astemizole, cisapride and terfenadine: miconazole inhibits the metabolism of these drugs and increases their concentration in blood plasma.

Carbamazepine: carbamazepine metabolism decreases.

Cyclosporine: increased risk of cyclosporin toxicity (renal dysfunction, cholestasis, paresthesia).

Fentanyl: the effect of opiates is increased or prolonged (CNS depression, depression, respiratory depression).

Phenytoin and phosphenytoin: the risk of phenytoin toxicity (ataxia, hyperlexia, nystagmus, tremor) increases.

Glimepiride: increased hypoglycemic effect.

Oxybutynin: increased plasma concentration or the action of oxybutynin (dry mouth, constipation, headache).

Oxycodone: the concentration of oxycodone in the blood plasma increases and its excretion decreases.

Pimozide: increased risk of cardiotoxicity (prolongation of the Q – T interval, flutter and ventricular fibrillation, cardiac arrest).

Tolterodine: the bioavailability of tolterodine in individuals with cytochrome P450 2D6 deficiency is increased.

Trimethrexate: increased toxicity of trimerexate (inhibition of bone marrow, impaired renal and hepatic function, and the formation of ulcers in the stomach and intestines).

Overdose

The drug is intended exclusively for vaginal use. there is no data on an overdose of metronidazole with vaginal administration. when introduced into the vagina, metronidazole can be absorbed in an amount sufficient to cause systemic effects. when applying an excessive amount of suppositories, systemic effects associated with metronidazole may occur, however, with intravaginal administration, metronidazole will not cause life-threatening symptoms.

If a large amount of the drug accidentally enters the digestive system, if necessary, use the appropriate gastric lavage method. Treatment should be carried out in cases where 12 g of metronidazole has entered the digestive system.

There is no specific antidote; symptomatic treatment is recommended. With an overdose of metronidazole, the following symptoms are noted: nausea, vomiting, abdominal pain, diarrhea, itching, metallic taste in the mouth, ataxia, vertigo, paresthesia, convulsions, leukopenia, darkening of the urine. With an overdose of miconazole nitrate, the following symptoms occur: nausea, vomiting, inflammation of the throat and oral cavity, anorexia, headache, diarrhea.

Metronidazole and its metabolites are well eliminated by hemodialysis.

Storage conditions

At a temperature not exceeding 25 ° C.