drugs

Metronidazole

Generality

Metronidazole is a nitroimidazolic antibiotic, used particularly against anaerobic bacteria. Developed in the 1960s, metronidazole has also proved effective in treating dermatological diseases, such as rosacea, and vegetating tumors. Metronidazole can be considered the antibiotic of choice against Clostridum difficile infection in the early stages of the disease.

In Europe and other countries, metronidazole is mainly marketed by the pharmaceutical company Sanofi-Aventis under the name Flagyl ®; in the United States of America it is marketed under the same name by Pfizer, while in Pakistan and Bangladesh is available under the name of Nidagyl ®, produced and marketed by the pharmaceutical company Star Laboratories; finally, in Thailand the drug is commercially found under the name of Mepagyl ®. Other names used are Rozex ®, MetroGel ® and Anabact ®; the latter are names of pharmaceutical preparations for cutaneous use, such as gels or creams. Metronidazole is often found on the market even under the name of the molecule itself, especially when it comes to injectable solutions.

What is it used for?

Frequent use of metronidazole, along with other antibiotics and proton pump inhibitors, is in triple therapy for the eradication of Helicobacter pylori.

Metronidazole is indicated in the treatment of asymptomatic trichomoniasis in females, and in the treatment of symptomatic trichomoniasis in males and in fair sex after the disease has been confirmed by specific laboratory procedures, such as crops.

Infection with Trichomonas vaginalis is a venereal disease; in this regard it is very important to treat the patient's or patient's sexual partner simultaneously, even when there are no symptoms. Metronidazole is also indicated for this type of treatment. In certain cases, when the partner is asymptomatic and laboratory tests are negative, it is the doctor's duty to strongly recommend the partner to undergo this treatment anyway, since in asymptomatic males it is often difficult to isolate the micro-organism; for this reason, in the absence of proper male therapy, there is the risk of a re-infection of the partner, ie of a relapse of the disease.

Metronidazole is indicated in the treatment of various infections caused by anaerobic bacteria, even in association with surgical procedures to treat these diseases. Among the most common infections caused by anaerobic bacteria, we can name intra-abdominal infections - which include peritonitis, liver abscesses and intra-abdominal abscesses - skin infections, gynecological infections - which include endometritis, lymphoma abscess of the ovarian tube and post-intervention vaginal infections - bacterial septicemia, meningitis and endocarditis.

It is advised that metronidazole treatment of serious infections caused by anaerobic bacteria begins with the administration of metronidazole intravenously, and then continues with an appropriate oral therapy. To avoid the appearance of resistant bacterial strains, it is recommended to use metronidazole only after confirmation - by bacterial culture and antibiogram - that microorganisms sensitive to the drug are involved; this is the only way to ensure that the infection will be eradicated.

Posology and method of use

The recommended dose of metronidazole to be used in triple therapy for the eradication of Helicobacter pylori ranges from 1000 mg / day to 1500 mg / day, depending on the other antibiotic with which it is associated. The minimum recommended duration of treatment is 14 days.

In the treatment of amebiasis in adults the recommended dose is 1500 mg of metronidazole per day, divided into three daily administrations for a period that can vary from 5 to 10 days depending on the individual pharmacological response. In children, instead, it is recommended to use 35 to 50 mg / kg / day, divided into three daily administrations for a period of 10 days.

In the treatment of pseudomembranous colitis in adults it is recommended to use 750 to 1500 mg / day of metronidazole, depending on the need, divided into 3 daily administrations. The duration of treatment can vary from 10 to 14 days. In children it is recommended to use 20 mg / kg / day (never exceeding 2000 mg / day), divided into 4 administrations, one every 6 hours, for a period of 10 days.

The recommended doses of metronidazole in surgical prophylaxis - especially in colon procedures - to avoid the appearance of contamination infections are: for preoperative treatment it is recommended to use 15 mg / kg of metronidazole for intravenous infusion for 30-60 minutes, a now before the intervention; for post-operative treatment it is instead recommended to use 7.5 mg / kg for intravenous infusion for 30-60 minutes, twice: the first after 6 hours from the preoperative dose and the second 12 hours after the preoperative dose.

In trichomoniasis treatment in adults, the recommended dose of metronidazole is 1000 mg / day, divided into two daily administrations over a 7-day period. Alternatively, 2000 mg / day can be administered once a day, for a period of 7 days. In children it is recommended to use 15-30 mg / kg / day of metronidazole, divided into three daily administrations for 7 days.

Metronidazole is also used to treat Crohn's disease ; in this case the recommended dose is 1000 mg / day, divided into 4 daily administrations, one every 6 hours. Initially it is advised to continue treatment with metronidazole for four to eight weeks. If a positive response is not obtained it is recommended to stop the treatment and to evaluate an alternative therapy; if instead a positive response to metronidazole is obtained, then the treatment can be prolonged up to 3 months; due to the dose-dependent side effects that can occur in long-term therapies, it is not recommended to continue with the treatment beyond 3 months.

In the treatment of giardiasis in adults it is recommended to use 750 mg / day of metronidazole, divided into three daily administrations, one every 8 hours; the recommended duration of the treatment is 7 days, but can be varied based on the severity of the infection. In children, however, it is recommended to use 15 mg / kg / day, divided into three daily administrations, one every 8 hours, for a period that can vary from 5 to 10 days.

In the treatment of pelvic inflammatory disease, the recommended dose of metronidazole is 1000 mg / day, divided into two daily administrations, one every 12 hours. Metronidazole is recommended by doctors in combination with doxycycline for ambulatory treatment of patients with pelvic inflammatory disease. Both antibiotics were used for two weeks. Other experts recommend instead that patients in the acute phase should be hospitalized and treated with antimicrobials for parenteral use.

Metronidazole is also used in the treatment of bacterial vaginosis . The recommended doses vary depending on the severity of the infection and the individual response to the treatment; the most common dose is 1000 mg / day, divided into two daily administrations, one every 12 hours for 7 days. Alternatively, 750 mg / day can be used, divided into three daily administrations, one every 8 hours for 7 days, or one 750 mg metronidazole prolonged-release tablet can be taken once a day, for 7 days. In some cases we also use 2000 mg / day taken in a single administration, always for 7 days. In children under 44 kilograms it is recommended instead to use 15 mg / kg / day divided into two daily administrations, for a week.

In the treatment of pneumonia ab ingestis the recommended dose of metronidazole is 7.5 mg / kg intravenously every six hours. It is advised to continue intravenous treatment until the clinical condition is stabilized and the fever is reduced, after which the oral metronidazole treatment can be started, for which the recommended doses are the same as for intravenous treatment.

In the treatment of bacteremia the recommended dose of metronidazole is 7.5 mg / kg every 6 hours intravenously; the recommended duration of treatment should be approximately two weeks, depending on the severity, nature of the infection and individual response to treatment. The same dose and the same treatment modalities are also used in the therapy of meningitis, against intra-abdominal infections, against peritonitis and against diverticulitis .

In the treatment of endocarditis, the recommended dose of metronidazole is 7.5 mg / kg, every 6 hours intravenously, while the duration of treatment can vary from 4 to 6 weeks, depending on the individual response and severity of the infection.

The recommended dose of metronidazole in the treatment of osteomyelitis is 7.5 mg / kg, every 6 hours, intravenously. Usually the duration of treatment is 4-6 weeks, depending on the severity of the infection: sometimes, especially when it comes to chronic osteomyelitis, an additional antibiotic treatment of one or two months may be necessary.

Metronidazole: contraindications and side effects »