| Item |
Information |
|
Drug Groups
|
approved |
|
Description
|
A nitroimidazole used to treat amebiasis; vaginitis; trichomonas infections; giardiasis; anaerobic bacteria; and treponemal infections. It has also been proposed as a radiation sensitizer for hypoxic cells. According to the Fourth Annual Report on Carcinogens (NTP 85-002, 1985, p133), this substance may reasonably be anticipated to be a carcinogen (Merck, 11th ed). |
| Indication |
For the treatment of anaerobic infections and mixed infections, surgical prophylaxis requiring anaerobic coverage, Clostridium difficile-associated diarrhea and colitis, Helicobacter pylori infection and duodenal ulcer disease, bacterial vaginosis, Giardia lamblia gastro-enteritis, amebiasis caused by Entamoeba histolytica, acne rosacea (topical treatment), and Trichomonas infections. |
| Pharmacology |
Metronidazole, a synthetic antibacterial and antiprotozoal agent of the nitroimidazole class, is used against protozoa such as Trichomonas vaginalis, amebiasis, and giardiasis. Metronidazole is extremely effective against anaerobic bacterial infections and is also used to treat Crohn's disease, antibiotic-associated diarrhea, and rosacea. |
| Toxicity |
LD50=500 mg/kg/day (orally in rat). Adverse effects include reversible peripheral neuropathy with prolonged therapy, CNS toxicity, disulfiram effect with alcohol, dark red-brown urine, metallic taste, nausea, epigastric distress, dizziness, vertigo and paresthesias associated with high doses, and neutropenia (reversible and mild). |
| Affected Organisms |
|
| Biotransformation |
Hepatic metabolism by hydroxylation, oxidation, and glucuronidation. |
| Absorption |
Well absorbed (at least 80%) with peak plasma concentrations achieved in 1-3 hours following oral administration of therapeutic doses of immediate release formulation. |
| Half Life |
6-8 hours |
| Protein Binding |
Less than 20% bound to plasma proteins. |
| References |
| • |
Shennan A, Crawshaw S, Briley A, Hawken J, Seed P, Jones G, Poston L: A randomised controlled trial of metronidazole for the prevention of preterm birth in women positive for cervicovaginal fetal fibronectin: the PREMET Study. BJOG. 2006 Jan;113(1):65-74.
[Pubmed]
|
| • |
Lamont RF: Can antibiotics prevent preterm birth--the pro and con debate. BJOG. 2005 Mar;112 Suppl 1:67-73.
[Pubmed]
|
| • |
Williams CS, Woodcock KR: Do ethanol and metronidazole interact to produce a disulfiram-like reaction? Ann Pharmacother. 2000 Feb;34(2):255-7.
[Pubmed]
|
| • |
Visapaa JP, Tillonen JS, Kaihovaara PS, Salaspuro MP: Lack of disulfiram-like reaction with metronidazole and ethanol. Ann Pharmacother. 2002 Jun;36(6):971-4.
[Pubmed]
|
|
| External Links |
|
|