Metronidazole for thrush?

Why is there a question mark in the title? Because Metronidazole is not an antifungal (antimycotic) drug, but an antibiotic and antiprotozoal drug. And if someone recommended you to use Metronidazole or its synonyms for thrush in women - Metrovagin, Metroseptol, Flagyl or Trichopolum, then this "someone" was wrong.

Does Metronidazole help with thrush?

The nitroimidazole antibiotic Metronidazole has a detrimental effect on peptostreptococci, clostridia, fusobacteria, porphyromonas, a large group of bacteroids and, as it turned out, even on Helicobacter. But, first of all, the indications for the use of this drug include diseases caused by such simple microorganisms (protozoa) or microbes as:

• Trichomonas vaginalis – the cause of trichomoniasis, and in men – trichomonas urethritis; Gardnerella vaginalis, which causes bacterial vaginosis (or gardnerellosis);
• the culprit of giardiasis Giardia intestinalis;
• Entamoeba histolytica is the causative agent of amebiasis.

According to the Infectious Diseases Society of America (IDSA), Metronidazole and another antibiotic, Clindamycin (which belongs to the lincosamide group), are the drugs of choice for treating bacterial vulvovaginosis in women. Their route of administration and dosage depend on whether the woman is pregnant or not, but in either case, treatment takes no more than five to seven days.

Metronidazole is also used for skin infections, rosacea, oral infections, pelvic inflammatory disease, Clostridium difficile-associated colitis, and gastric ulcers with a positive Helicobacter pylori test.

But yeast-like fungi Candida (candida), which are the cause of thrush, that is, candidal vaginitis, are not included in the list of indications for Metronidazole, and all this can be found out by reading the instructions for its use.

So, Metronidazole for thrush in women and men - any form of release of this drug (injection solution, tablets, gel, suppositories) - will not help. And its prescription can be justified only in those cases when during the laboratory examination of a smear from the vagina, and in men - from the urethra, not only a fungal infection is detected, but also a bacterial one.

Then it is advisable to use combination drugs, for example, vaginal tablets Klion D, which contain metronidazole and the antifungal agent miconazole in equal proportions.

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Why doesn't Metronidazole help with thrush?

To make all of the above more convincing, it is necessary to explain in general terms how Metronidazole works, that is, what its pharmacodynamics are.

Essentially selective for anaerobic bacteria and protozoa, Metronidazole is a prodrug in the form of a non-ionized substance that becomes active upon contact with these microorganisms.

Metronidazole is activated only by anaerobic microorganisms that have a special enzyme, ferredoxin oxidoreductase (POR), which reduces the nitro group of the drug (NO ₂ ) to form a reactive metabolite that interacts with the DNA of microbes and protozoa.

As a result of this interaction, the biosynthesis of amino acids in the cells of microorganisms slows down, and without proteins their reproduction becomes impossible.

At the same time, Metronidazole does not affect most aerobic bacteria, as well as fungal infections (including Candida albicans), because they lack the POR enzyme and are not able to activate the active substance of this drug.

What helps with thrush?

All standard treatment regimens for uncomplicated vulvovaginal candidiasis work equally well, even if you take it orally once (at a dose of 150 mg) and then take Fluconazole for thrush again three days later (other commercial names are Flucostat Diflucan, Difluzol, Mikomaks, Fucis). Fluconazole capsules, a systemic antifungal agent of the azole group, are effective for both candidal vaginitis in women and thrush in men. Read also - Antifungal drugs for thrush in men.

You can carry out treatment for a week using another azole antifungal drug - Clotrimazole for thrush, in the form of suppositories of the same name or using their analogues - vaginal tablets Candibene or Gine-Lotrimin.

The results of clinical trials and positive feedback from practicing doctors became the basis for the approval of Fluconazole and Clotrimazole by the US FDA and the European Medicines Agency (EMEA). More information in the material - Effective treatment of candidiasis with tablets

For local treatment, it is customary to use a variety of suppositories for thrush, in particular:

• suppositories with polyene antifungal antibiotics - Levorin and Nystatin for thrush;
• globules with nystatin and nifuratel Macmiror;
• suppositories with the polyene antibiotic natamycin Pimafucin for thrush;
• Livarol suppositories (with ketoconazole);
• suppositories with miconazole Ginezol;
• Ekalin and Gino-Pevaryl with econazole.

Most often, their use during pregnancy is allowed only from the second trimester and according to strict indications of an obstetrician-gynecologist. More details –

Treatment of thrush during pregnancy

And the use for children is discussed in the publication - Candidal infection (candidiasis, thrush) in children

Can Metronidazole Cause Yeast Infections?

As is known, all antibiotics promote the development of fungal infections, including bronchopulmonary and gastrointestinal spread of Candida as a nosocomial infection, by the way, the most common of those acquired in the hospital.

As studies show, also after systemic antibacterial therapy, including the use of Metronidazole, increased colonization of the oropharyngeal tract and vagina by Candida is common - with the development of vulvovaginal candidiasis, that is, thrush.

Why can antibacterial drugs, including Metronidazole, cause thrush? Experts explain the prevalence of candidiasis among people taking antibiotics by the fact that antibiotics kill bacteria that normally live in the body, and in the absence of "competition" Candida begins to multiply unhindered.

Some forms of candidiasis, such as invasive candidiasis of the heart valves, spleen, kidneys, as well as candidemia (the entry of the fungus into the systemic bloodstream with the development of neutropenia) are very dangerous.

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