443-48-1

Raw materials And Preparation Products

Hazard Information

Material Safety Data Sheet(MSDS)

Questions And Answer

• Antibacterial Spectrum

  In addition to being used for anti-trichomoniasis and anti-ameba, in recent years, metronidazole has been widely used in anti-anaerobic infection. The nitro group of this product is reduced to amino group in an anaerobic environment and shows the effect of anti-anaerobic bacteria, but it is ineffective against aerobic bacteria or facultative aerobic bacteria. It has good antibacterial effect on the following anaerobic bacteria: ① Bacteroides, including Bacteroides fragilis; ② Clostridium; ③ Clostridium, including Tetanus; ④ Partial Eubacterium; ⑤ Peptococcus and Digestive Streptococcus etc.;

• Brand Name(s)

  Flagyl and generic ;

• Indications and Usage

  Metronidazole is a nitroimidazole antibiotic, also known as metronidazol and novonidazol. It was initially used to treat vaginal trichomaniasis, with very significant clinical effects. It is broadly used to prevent and treat oral anaerobic infections. In hospitals, it has been used frequently to prevent and treat respiratory, gastrointestinal, peritoneal, pelvic, skin, soft tissue, joint, and brain infections, cardiomyitis, and septicemia caused by anaerobic bacteria. The effectiveness of Metronidazole towards treating body tissue and intestinal amoebiasis is significant, and it the preferred drug to treat parasitosis. ;

• Mechanisms of Action

  Metronidazole kills anaerobic microorganisms, and its metabolites in the body during reduction also inhibit them by inhibiting DNA synthesis, thus interfering with bacterial growth and propagation, eventually killing them. Anaerobic bacteria affected include: Bacteroides fragilis, Fusobacterium (so named because of its sharp fusiform shape at both ends,) Clostridium tetani, Peptostreptococcus, and Giardia lamblia. Its mechanism of action in the treatment of parasites is to disrupt protozoans’ nitrogen chains by inhibiting their redox reactions. In vitro experiments have shown that at concentrations of 1-2 mg/L, morphological changes occurred in dissolved amoeba starting at 6-20 hours, killing them all within 24 hours. At a concentration of 0.2 mg/L, dissolved bacteria were killed within 72 hours. ;

• Warnings and Precautions

  Interactions with nitroimidazole antibiotics, ethanol, and nicotine interfere with the oxidation of ethanol and can cause disulfiram reactions, causing symptoms like faster heart rate and decreased blood pressure, so patients should avoid contact with alcohol and smoke less during treatment in order to prevent the occurrence of adverse reactions. ;

• Methods of production

  It is synthetized by 2-methyl-5-nitro imidazole (see 25010) and ethylene oxide addition. 2-methyl-5-nitro imidazole dissolved in formic acid and at 30-40℃ successive adding epoxy ethane, and sulfuric acid in the middle of adding feeding. and reaction for 1 h, after that. Decompression to recycle formic acid, water solution is cooled to 10 ℃, filter. The filtrate with sodium hydroxide solution to adjust pH = 10. Set aside to cool, filtering, washing to nearly alterations into neutral, recrystallization in water. Activated carbon decolorization to get metronidazole. ;

• Pharmacology and mechanism of action

  Metronidazole is a 5-nitroimidazole derivative which was originally introduced against Trichomonas vaginalis in 1960. Soon it was shown to possess a broad spectrum of activity against other protozoal infections such as amoebiasis and giardiasis, and more recently against infections due to anaerobic bacteria ^[1]. The mechanism of action of metronidazole is not well understood. In the parasite, the 5-nitro group of the drug undergoes reductive transformation to a cytotoxic intermediate which binds to the helical structure of the DNA leading to strand breakage and eventual cell death ^[2]. ;

• Indications

  Against infections caused by Trichomonas vaginalis, Entamoeba histolytica (acute intestinal type and liver abscesses), Giardia lamblia and Dracunculus medinensis. During treatment of trichomoniasis it is wise to treat the male partner as well. In amoebiasis, a luminal amoebicide is added to eliminate surviving organisms in the colon. Metronidazole is also used for the treatment of infections due to anaerobic bacteria. ;

• Side effects

  Side effects with doses used to treat protozoal infections are usually mild, reversible and self-limiting and may affect 4% to 5% of treated patients. The most common are gastrointestinal disturbances (nausea, vomiting, epigastric pain, metallic taste, furring of the tongue), intolerance to alcohol (disulfiram-like effect) and central nervous system effects (headache, dizziness and sleepiness) ^[3]. Other side effects reported include urticaria, darkening of the urine with a reddish-brown discoloration and transient neutropenia ^[4]. During prolonged high doses, the drug may cause severe neurotoxic side effects such as peripheral neuropathy, paraesthesia and epileptiform seizures ^[3,4]. Few case reports of bone marrow depression ^[5], gynecomastia ^[6] and acute pancreatitis ^[7] have been reported. Although metronidazole is mutagenic in bacteria and carcinogenic in rodents, no association with human cancer has been proven . ;

• Contraindications and precautions

  Dosage reductions should be made in patients with severe hepatic failure. Because of its potential neurotoxicity and neutropenia the drug should be given with caution to patients with diseases of the CNS or with a history of blood dyscrasia. Patients should be warned of a disulfiram-like reaction if the drug is taken together with alcohol. Metronidazole should be used with extra caution in patients being treated with warfarin (see interactions). ;

• Interactions

  Metronidazole is a weak inhibitor of alcohol dehydrogenase. Simultaneous administration of metronidazole and disulfiram has been reported to cause an acute psychosis or mental confusion. This effect was observed in 6 of 29 chronic alcoholic men given both drugs, but in none of those given placebo plus disulfiram ^[8]. Metronidazole inhibits the ring oxidation of S (+) warfarin and significant bleeding can occur if the two drugs are taken together ^[9]. Significant increase of hepatic clearance of metronidazole has been reported when the drug was taken together with phenobarbital ^{[10, 11]} or prednisone ^[11]. ;

• Preparations

  Many preparations are available apart from those mentioned below. Available as metronidazole
  • Elyzol® (Dumex). Solution for infusion 5 mg/ml. Tablets 250 mg, 500 mg. Suppositories 500 mg, 1000 mg.
  • Flagyl® (Rhône-Poulenc Rorer). Solution for infusion 5 mg/ml. Tablets 200 mg, 400 mg. Suppositories 500 mg, 1000 mg.
  • Servizol® (Servipharm). Tablets 200 mg, 250 mg.
  Available as metronidazole benzoate: 10 mg metronidazole benzoate is equivalent to 6.2 mg metronidazole.
  • Elyzol (Dumex)® Oral solution 25 mg metronidazole base/ml.
  • Flagyl® (Rhône-Poulenc Rorer). Oral solution 40 mg metronidazole base/ml. ;

• References

  1. Scully BE (1988). Metronidazole. Med Clin North Amer, 72, 613–621.
  2. Muller M (1983). Mode of action of metronidazole on anaerobic bacteria and protozoa. Surgery, 93, 165–171.
  3. Lau AH, Lam NP, Piscitelli SS (1992). Clinical pharmacokinetics of metronidazole and other nitroimidazole anti-infectives. Clin Pharmacokinet, 23, 328–364.
  4. Roe FJC (1985). Safety of nitroimidazoles. Scand J Infect Dis, 46, 72–81.
  5. Heisterberg L, Branebjerg PE (1983). Blood and milk concentrations of metronidazole in mothers and infants. J Perinat Med, 11, 114–120.
  6. Fagan TC, Johnson DG, Grosso DS (1985). Metronidazole-induced gynecomastia. J Am Med Ass, 254, 3217.
  7. Poltkin BH, Cohen I, Tsang T, Cullinane T (1985). Metronidazole-induced pancreatitis. Ann Intern Med, 103, 891–892.
  8. Rothstein E, Clancy DD (1969). Toxicity of disulfiram combined with metronidazole. N Engl J Med, 280, 1006–1007.
  9. O’Reilly RA (1976). The stereoselective interaction of warfarin and metronidazole in man. N Engl J Med, 295, 354–357.
  10. Gupte S (1983). Phenobarbital and metabolism of metronidazole. N Engl J Med, 308, 529. 11. Eradiri D, Jamali R, Thomson ABR (1988). Interaction of metronidazole with phenobarbital, cimetidine, prednisone, and sulphasalzine in Crohn’s disease. Biopharmaceut Drug Disp, 9, 219– 227. ;

Spectrum Detail

Supplier

Related Products