Metronidazole

Metronidazole

Clinical data
Pronunciation	/mɛtrəˈnaɪdəzoʊl/
Trade names	Flagyl, Metro, others
AHFS/Drugs.com	Monograph
License data	US FDA: Metronidazole
Pregnancy category	AU: B2 US: B (No risk in non-human studies)
Routes of administration	by mouth, topical, rectal, IV, vaginal
ATC code	A01AB17 (WHO) , D06BX01 (WHO), G01AF01 (WHO), J01XD01 (WHO), P01AB01 (WHO), QP51AA01 (WHO)
Legal status
Legal status	AU: S4 (Prescription only) CA: ℞-only UK: POM (Prescription only) US: ℞-only
Pharmacokinetic data
Bioavailability	80% (oral), 60–80% (rectal), 20–25% (vaginal)
Protein binding	20%
Metabolism	Hepatic
Biological half-life	8 hours
Excretion	Urine (77%), faeces (14%)
Identifiers
IUPAC name 2-(2-methyl-5-nitro-1H-imidazol-1-yl)ethanol
CAS Number	443-48-1 Y
PubChem CID	4173
DrugBank	DB00916 Y
ChemSpider	4029 Y
UNII	140QMO216E
KEGG	D00409 Y
ChEBI	CHEBI:6909 Y
ChEMBL	CHEMBL137 Y
NIAID ChemDB	007953
PDB ligand	2MN (PDBe, RCSB PDB)
ECHA InfoCard	100.006.489
Chemical and physical data
Formula	C6H9N3O3
Molar mass	171.15 g/mol
3D model (Jmol)	Interactive image
Melting point	159 to 163 °C (318 to 325 °F)
SMILES OCCn1c(C)ncc1[N+](=O)[O-]
InChI InChI=1S/C6H9N3O3/c1-5-7-4-6(9(11)12)8(5)2-3-10/h4,10H,2-3H2,1H3 Y Key:VAOCPAMSLUNLGC-UHFFFAOYSA-N Y

Metronidazole (MNZ), marketed under the brand name Flagyl among others, is an antibiotic and antiprotozoal medication. It is used either alone or with other antibiotics to treat pelvic inflammatory disease, endocarditis, and bacterial vaginosis. It is effective for dracunculiasis, giardiasis, trichomoniasis, and amebiasis. It is the drug of choice for a first episode of mild-to-moderate Clostridium difficile colitis. Metronidazole is available by mouth, as a cream, and intravenously.

Common side effects include nausea, a metallic taste, loss of appetite, and headaches. Occasionally seizures or allergies to the medication may occur. Some state that metronidazole should not be used in early pregnancy while others state doses for trichomoniasis are okay. It should not be used when breastfeeding.

Metronidazole began to be commercially used in 1960 in France. It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system. It is available in most areas of the world. The pills are relatively inexpensive, costing between 0.01 and 0.10 USD each. In the United States it is about 26 USD for ten days of treatment.

Metronidazole is primarily used to treat: bacterial vaginosis, pelvic inflammatory disease (along with other antibacterials like ceftriaxone), pseudomembranous colitis, aspiration pneumonia, rosacea (topical), fungating wounds (topical), intra-abdominal infections, lung abscess, periodontitis, amoebiasis, oral infections, giardiasis, trichomoniasis, and infections caused by susceptible anaerobic organisms such as Bacteroides, Fusobacterium, Clostridium, , and Prevotella species. It is also often used to eradicate Helicobacter pylori along with other drugs and to prevent infection in people recovering from surgery.