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Details

Stereochemistry RACEMIC
Molecular Formula C12H15N3O9
Molecular Weight 345.2622
Optical Activity ( + / - )
Defined Stereocenters 0 / 1
E/Z Centers 0
Charge 0

SHOW SMILES / InChI
Structure of metronidazole citrate

SMILES

CC1=NC=C(N1CCOC(=O)CC(O)(CC(O)=O)C(O)=O)[N+]([O-])=O

InChI

InChIKey=BSDGJHSABQWHHI-UHFFFAOYSA-N
InChI=1S/C12H15N3O9/c1-7-13-6-8(15(22)23)14(7)2-3-24-10(18)5-12(21,11(19)20)4-9(16)17/h6,21H,2-5H2,1H3,(H,16,17)(H,19,20)

HIDE SMILES / InChI

Molecular Formula C12H15N3O9
Molecular Weight 345.2622
Charge 0
Count
Stereochemistry RACEMIC
Additional Stereochemistry No
Defined Stereocenters 0 / 1
E/Z Centers 0
Optical Activity ( + / - )

Description
Curator's Comment: description was created based on several sources, including http://www.emedexpert.com/facts/metronidazole-facts.shtml

Metronidazole was synthesized by France's Rhone-Poulenc laboratories and introduced in the mid-1950s under the brand name Flagel in the US, while Sanofi-Aventis markets metronidazole globally under the same trade name, Flagyl, and also by various generic manufacturers. Metronidazole is one of the rare examples of a drug developed as ant parasitic, which has since gained broad use as an antibacterial agent. Metronidazole, a nitroimidazole, exerts antibacterial effects in an anaerobic environment against most obligate anaerobes. Metronidazole is indicated for the treatment of the following infections due to susceptible strains of sensitive organisms: Trichomoniasis: symptomatic, asymptomatic, asymptomatic consorts; Amebiasis: acute intestinal amebiasis (amebic dysentery) and amebic liver abscess; Anaerobic bacterial infections; Intra-abdominal infections, including peritonitis, intra-abdominal abscess, and liver abscess; Skin and skin structure infections; Gynecologic infections, including endometritis, endomyometritis, tubo-ovarian abscess, and postsurgical vaginal cuff infection; Bacterial septicemia; Bone and joint infections, as adjunctive therapy; Central Nervous System infections, including meningitis and brain abscess; Lower Respiratory Tract infections, including pneumonia, empyema, and lung abscess; Endocarditis. Metronidazole is NOT effective for infections caused by aerobic bacteria that can survive in the presence of oxygen. Metronidazole is only effective against anaerobic bacterial infections because the presence of oxygen will inhibit the nitrogen-reduction process that is crucial to the drug's mechanism of action. Once metronidazole enters the organism by passive diffusion and activated in the cytoplasm of susceptible anaerobic bacteria, it is reduced; this process includes intracellular electron transport proteins such as ferredoxin, transfer of an electron to the nitro group of the metronidazole, and formation of a short-lived nitroso free radical. Because of this alteration of the metronidazole molecule, a concentration gradient is created and maintained which promotes the drug’s intracellular transport. The reduced form of metronidazole and free radicals can interact with DNA leading to inhibition of DNA synthesis and DNA degradation leading to death of the bacteria. The precise mechanism of action of metronidazole is unknown. Metronidazole has a limited spectrum of activity that encompasses various protozoans and most Gram-negative and Gram-positive anaerobic bacteria. Metronidazole has activity against protozoans like Entamoeba histolytica, Giardia lamblia and Trichomonas vaginalis, for which the drug was first approved as an effective treatment.

CNS Activity

Curator's Comment: In animal studies, metronidazole readily penetrated the blood-CSF/blood-brain barrier, and data regarding the entry into human CSF and brain abscess confirmed this finding

Originator

Curator's Comment: was synthesized by France's Rhone-Poulenc laboratories and introduced in the mid-1950s under the brand name Flagyl

Approval Year

Targets

Targets

Primary TargetPharmacologyConditionPotency
Conditions

Conditions

ConditionModalityTargetsHighest PhaseProduct
Curative
FLAGYL

Approved Use

INDICATIONS & USAGE Metronidazole vaginal gel USP, 0.75% is indicated in the treatment of bacterial vaginosis (formerly referred to as Haemophilus vaginitis, Gardnerella vaginitis, nonspecific vaginitis, Corynebacterium vaginitis, or anaerobic vaginosis). NOTE: For purposes of this indication, a clinical diagnosis of bacterial vaginosis is usually defined by the presence of a homogeneous vaginal discharge that (a) has a pH of greater than 4.5, (b) emits a “fishy” amine odor when mixed with a 10% KOH solution, and (c) contains clue cells on microscopic examination. Gram’s stain results consistent with a diagnosis of bacterial vaginosis include (a) markedly reduced or absent Lactobacillus morphology, (b) predominance of Gardnerella morphotype, and (c) absent or few white blood cells. Other pathogens commonly associated with vulvovaginitis, e.g., Trichomonas vaginalis, Chlamydia trachomatis, N. gonorrhoeae, Candida albicans, and Herpes simplex virus should be ruled out.

Launch Date

1963
Curative
FLAGYL

Approved Use

INDICATIONS & USAGE Metronidazole vaginal gel USP, 0.75% is indicated in the treatment of bacterial vaginosis (formerly referred to as Haemophilus vaginitis, Gardnerella vaginitis, nonspecific vaginitis, Corynebacterium vaginitis, or anaerobic vaginosis). NOTE: For purposes of this indication, a clinical diagnosis of bacterial vaginosis is usually defined by the presence of a homogeneous vaginal discharge that (a) has a pH of greater than 4.5, (b) emits a “fishy” amine odor when mixed with a 10% KOH solution, and (c) contains clue cells on microscopic examination. Gram’s stain results consistent with a diagnosis of bacterial vaginosis include (a) markedly reduced or absent Lactobacillus morphology, (b) predominance of Gardnerella morphotype, and (c) absent or few white blood cells. Other pathogens commonly associated with vulvovaginitis, e.g., Trichomonas vaginalis, Chlamydia trachomatis, N. gonorrhoeae, Candida albicans, and Herpes simplex virus should be ruled out.

Launch Date

1963
Curative
FLAGYL

Approved Use

INDICATIONS & USAGE Metronidazole vaginal gel USP, 0.75% is indicated in the treatment of bacterial vaginosis (formerly referred to as Haemophilus vaginitis, Gardnerella vaginitis, nonspecific vaginitis, Corynebacterium vaginitis, or anaerobic vaginosis). NOTE: For purposes of this indication, a clinical diagnosis of bacterial vaginosis is usually defined by the presence of a homogeneous vaginal discharge that (a) has a pH of greater than 4.5, (b) emits a “fishy” amine odor when mixed with a 10% KOH solution, and (c) contains clue cells on microscopic examination. Gram’s stain results consistent with a diagnosis of bacterial vaginosis include (a) markedly reduced or absent Lactobacillus morphology, (b) predominance of Gardnerella morphotype, and (c) absent or few white blood cells. Other pathogens commonly associated with vulvovaginitis, e.g., Trichomonas vaginalis, Chlamydia trachomatis, N. gonorrhoeae, Candida albicans, and Herpes simplex virus should be ruled out.

Launch Date

1963
Cmax

Cmax

ValueDoseCo-administeredAnalytePopulation
16.54 mg/L
15 mg/kg single, intravenous
dose: 15 mg/kg
route of administration: intravenous
experiment type: single
co-administered:
METRONIDAZOLE plasma
Homo sapiens
population: unhealthy
age: CHILD
sex: UNKNOWN
food status: UNKNOWN
6.77 μg/mL
250 mg single, oral
dose: 250 mg
route of administration: Oral
experiment type: SINGLE
co-administered:
METRONIDAZOLE plasma
Homo sapiens
population: HEALTHY
age: ADULT
sex: FEMALE / MALE
food status: FASTED
6 μg/mL
250 mg single, oral
dose: 250 mg
route of administration: Oral
experiment type: SINGLE
co-administered:
METRONIDAZOLE plasma
Homo sapiens
population: UNKNOWN
age: ADULT
sex: UNKNOWN
food status: UNKNOWN
12 μg/mL
500 mg single, oral
dose: 500 mg
route of administration: Oral
experiment type: SINGLE
co-administered:
METRONIDAZOLE plasma
Homo sapiens
population: UNKNOWN
age: ADULT
sex: UNKNOWN
food status: UNKNOWN
40 μg/mL
2000 mg single, oral
dose: 2000 mg
route of administration: Oral
experiment type: SINGLE
co-administered:
METRONIDAZOLE plasma
Homo sapiens
population: UNKNOWN
age: ADULT
sex: UNKNOWN
food status: UNKNOWN
25 μg/mL
7.5 mg/kg 4 times / day steady-state, intravenous
dose: 7.5 mg/kg
route of administration: Intravenous
experiment type: STEADY-STATE
co-administered:
METRONIDAZOLE plasma
Homo sapiens
population: UNHEALTHY
age: ADULT
sex: UNKNOWN
food status: UNKNOWN
AUC

AUC

ValueDoseCo-administeredAnalytePopulation
75.23 μg × h/mL
250 mg single, oral
dose: 250 mg
route of administration: Oral
experiment type: SINGLE
co-administered:
METRONIDAZOLE plasma
Homo sapiens
population: HEALTHY
age: ADULT
sex: FEMALE / MALE
food status: FASTED
T1/2

T1/2

ValueDoseCo-administeredAnalytePopulation
7.76 h
250 mg single, oral
dose: 250 mg
route of administration: Oral
experiment type: SINGLE
co-administered:
METRONIDAZOLE plasma
Homo sapiens
population: HEALTHY
age: ADULT
sex: FEMALE / MALE
food status: FASTED
8 h
250 mg single, oral
dose: 250 mg
route of administration: Oral
experiment type: SINGLE
co-administered:
METRONIDAZOLE plasma
Homo sapiens
population: UNKNOWN
age: ADULT
sex: UNKNOWN
food status: UNKNOWN
8 h
500 mg single, oral
dose: 500 mg
route of administration: Oral
experiment type: SINGLE
co-administered:
METRONIDAZOLE plasma
Homo sapiens
population: UNKNOWN
age: ADULT
sex: UNKNOWN
food status: UNKNOWN
8 h
2000 mg single, oral
dose: 2000 mg
route of administration: Oral
experiment type: SINGLE
co-administered:
METRONIDAZOLE plasma
Homo sapiens
population: UNKNOWN
age: ADULT
sex: UNKNOWN
food status: UNKNOWN
8 h
unknown, oral
METRONIDAZOLE plasma
Homo sapiens
population: HEALTHY
age: ADULT
sex: UNKNOWN
food status: UNKNOWN
Funbound

Funbound

ValueDoseCo-administeredAnalytePopulation
80%
unknown, oral
METRONIDAZOLE plasma
Homo sapiens
population: HEALTHY
age: ADULT
sex: UNKNOWN
food status: UNKNOWN
Doses

Doses

DosePopulationAdverse events​
12.5 g single, oral
Overdose
Dose: 12.5 g
Route: oral
Route: single
Dose: 12.5 g
Sources:
unhealthy, 58 years
Health Status: unhealthy
Age Group: 58 years
Sex: F
Sources:
Disc. AE: Hepatotoxicity...
AEs leading to
discontinuation/dose reduction:
Hepatotoxicity (9.6%)
Sources:
8.5 g single, oral
Overdose
Dose: 8.5 g
Route: oral
Route: single
Dose: 8.5 g
Sources:
unhealthy, 62 years
Health Status: unhealthy
Age Group: 62 years
Sex: M
Sources:
1000 mg/m2 3 times / day steady, oral
Highest studied dose
Dose: 1000 mg/m2, 3 times / day
Route: oral
Route: steady
Dose: 1000 mg/m2, 3 times / day
Sources:
unhealthy, adult
Health Status: unhealthy
Age Group: adult
Sex: unknown
Sources:
DLT: Nausea and vomiting, Generalised onset motor seizure...
Dose limiting toxicities:
Nausea and vomiting (13.5%)
Generalised onset motor seizure (12.8%)
Neurotoxicity NOS (10.9%)
Sources:
5.3 mg/m2 3 times / week multiple, oral
Highest studied dose
Dose: 5.3 mg/m2, 3 times / week
Route: oral
Route: multiple
Dose: 5.3 mg/m2, 3 times / week
Sources:
unhealthy, adult
Health Status: unhealthy
Age Group: adult
Sex: unknown
Sources:
DLT: Gastrointestinal toxicity, Central nervous system toxicity...
Dose limiting toxicities:
Gastrointestinal toxicity (14.5%)
Central nervous system toxicity (13.7%)
Sources:
1350 mg 3 times / day steady, oral
Overdose
Dose: 1350 mg, 3 times / day
Route: oral
Route: steady
Dose: 1350 mg, 3 times / day
Sources:
unhealthy, preterm newborn
Health Status: unhealthy
Age Group: preterm newborn
Sex: F
Sources:
AEs

AEs

AESignificanceDosePopulation
Hepatotoxicity 9.6%
Disc. AE
12.5 g single, oral
Overdose
Dose: 12.5 g
Route: oral
Route: single
Dose: 12.5 g
Sources:
unhealthy, 58 years
Health Status: unhealthy
Age Group: 58 years
Sex: F
Sources:
Neurotoxicity NOS 10.9%
DLT
1000 mg/m2 3 times / day steady, oral
Highest studied dose
Dose: 1000 mg/m2, 3 times / day
Route: oral
Route: steady
Dose: 1000 mg/m2, 3 times / day
Sources:
unhealthy, adult
Health Status: unhealthy
Age Group: adult
Sex: unknown
Sources:
Generalised onset motor seizure 12.8%
DLT
1000 mg/m2 3 times / day steady, oral
Highest studied dose
Dose: 1000 mg/m2, 3 times / day
Route: oral
Route: steady
Dose: 1000 mg/m2, 3 times / day
Sources:
unhealthy, adult
Health Status: unhealthy
Age Group: adult
Sex: unknown
Sources:
Nausea and vomiting 13.5%
DLT
1000 mg/m2 3 times / day steady, oral
Highest studied dose
Dose: 1000 mg/m2, 3 times / day
Route: oral
Route: steady
Dose: 1000 mg/m2, 3 times / day
Sources:
unhealthy, adult
Health Status: unhealthy
Age Group: adult
Sex: unknown
Sources:
Central nervous system toxicity 13.7%
DLT
5.3 mg/m2 3 times / week multiple, oral
Highest studied dose
Dose: 5.3 mg/m2, 3 times / week
Route: oral
Route: multiple
Dose: 5.3 mg/m2, 3 times / week
Sources:
unhealthy, adult
Health Status: unhealthy
Age Group: adult
Sex: unknown
Sources:
Gastrointestinal toxicity 14.5%
DLT
5.3 mg/m2 3 times / week multiple, oral
Highest studied dose
Dose: 5.3 mg/m2, 3 times / week
Route: oral
Route: multiple
Dose: 5.3 mg/m2, 3 times / week
Sources:
unhealthy, adult
Health Status: unhealthy
Age Group: adult
Sex: unknown
Sources:
OverviewDrug as perpetrator​

Drug as perpetrator​

TargetModalityActivityMetaboliteClinical evidence
no
no
no
no
no
no
no
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
PubMed

PubMed

TitleDatePubMed
[Antiamebic effect of metronidazole proved in a study conducted in Cienfuegos province].
2005-04-27
[Efficacy of two Helicobacter pylori eradication treatments in children with recurrent abdominal pain].
2005-03-11
Is operative management effective in treatment of perforated typhoid?
2005-03
[Two cases of metronidazole-induced encephalopathy].
2005-03
Abnormal enhancing lesion of dentate nuclei causing neurologic symptoms induced by metronidazole toxicity.
2005-03
Can antibiotics prevent preterm birth--the pro and con debate.
2005-03
Analyses of recombinant vaccinia and fowlpox vaccine vectors expressing transgenes for two human tumor antigens and three human costimulatory molecules.
2005-02-15
Phase I study of sequential vaccinations with fowlpox-CEA(6D)-TRICOM alone and sequentially with vaccinia-CEA(6D)-TRICOM, with and without granulocyte-macrophage colony-stimulating factor, in patients with carcinoembryonic antigen-expressing carcinomas.
2005-02-01
Reversible cerebellar lesions induced by metronidazole therapy for helicobacter pylori.
2004-10
Metronidazole-induced encephalopathy.
2004-09-15
Thoracic spondylitis from a mycotic (Streptococcus pneumoniae) aortic aneurysm: a case report.
2004-09-01
TRICOM: enhanced vaccines as anticancer therapy.
2004-08
[Tetanus in cats: 3 case descriptions].
2004-06
Perforated appendicitis: is laparoscopy safe?
2004-05-04
Reproductive and cytogenetic toxicity of metronidazole in male mice.
2004-05
Experience with routine intraabdominal cultures during laparoscopic gastric bypass with implications for antibiotic prophylaxis.
2004-05
A case of clarithromycin-induced manic episode (antibiomania).
2004-03
Nitazoxanide: a new broad spectrum antiparasitic agent.
2004-02
Lemierre's syndrome: the forgotten disease. An unusual presentation of sepsis.
2004-02
Reduced stem cell mobilization in mice receiving antibiotic modulation of the intestinal flora: involvement of endotoxins as cofactors in mobilization.
2004-01-01
Crohn's disease--when to operate?
2004
[Clinical analysis of unsuccessful Helicobacter pylori eradication].
2004
[Use of arilin (Dr.Wolff) in the treatment of bacterial vaginosis and trichomoniasis during the period of 01.10.2003-31.12.2003].
2004
Solvent effects in permeation assessed in vivo by skin surface biopsy.
2003-12-18
Metronidazole-induced encephalopathy and inferior olivary hypertrophy: lesion analysis with diffusion-weighted imaging and apparent diffusion coefficient maps.
2003-12
Ruthenium(II) sulfoxide-maltolato and -nitroimidazole complexes: synthesis and MTT assay.
2003-11-17
Modified vaccinia virus ankara recombinants are as potent as vaccinia recombinants in diversified prime and boost vaccine regimens to elicit therapeutic antitumor responses.
2003-11-15
Bone defects of the facial skeleton - replacement with biomaterials.
2003-11
A comparison of 15% azelaic acid gel and 0.75% metronidazole gel in the topical treatment of papulopustular rosacea: results of a randomized trial.
2003-11
Bronchospasm and laryngeal stridor as an adverse effect of oxytocin treatment.
2003-10
Cardiac diphtheria in a previously immunized individual.
2003-09
MR imaging and diffusion-weighted imaging changes in metronidazole (Flagyl)-induced cerebellar toxicity.
2003-09
Analysis of antimicrobial susceptibility and virulence factors in Helicobacter pylori clinical isolates.
2003-08-11
An open label crossover trial of effects of metronidazol on hyperlipidaemia.
2003-08
Complete remission of Crohn's disease after high-dose cyclophosphamide and autologous stem cell transplantation.
2003-08
Renal papillary necrosis induced by naproxen.
2003-08
[Evaluation on monkeys of reactogenicity and effectiveness of the complex immunoglobulin preparation formulation].
2003-07-31
Superior mesenteric vein thrombosis following laparoscopic Nissen fundoplication.
2003-07-15
Molecular mechanisms and biological significance of CTL avidity.
2003-07
Diazepam as a treatment for metronidazole toxicosis in dogs: a retrospective study of 21 cases.
2003-05-31
A triad of costimulatory molecules synergize to amplify T-cell activation in both vector-based and vector-infected dendritic cell vaccines.
2003-05
[Vulvar amebiasis. Report of a case and review of the literature].
2003-02
The importance of Bi-Digital O-Ring Test in the treatment of multiple hepatic abscesses: a case history.
2003
[Microbiologic characteristics of wound infectious process in use of ion-exchange sorbents].
2003
[Anaerobic bacteria in bronchoalveolar lavage fluid (BAL) after thoracic surgery].
2003
[Comparative clinical and epidemiological evaluation of beta-lactam antibiotics in the treatment of intraabdominal infections].
2003
An unexpected and severe neurological disorder with permanent disability acquired during short-course treatment with metronidazole.
2003
The effect of therapeutic drugs used in inflammatory bowel disease on the incidence and growth of colonic cancer in the dimethylhydrazine rat model.
1992-11
Treatment of experimental pneumocystosis: review of 7 years of experience and development of a new system for classifying antimicrobial drugs.
1992-09
Endpoints of spermatotoxicity in the rat after short duration exposures to fourteen reproductive toxicants.
1992
Patents

Sample Use Guides

Trichomoniasis: In the Female: One-day treatment − two grams of FLAGYL, given ither as a single dose or in two divided doses of one gram each, given in the same day. Anaerobic Bacterial Infections: In the treatment of most serious anaerobic infections, intravenous metronidazole is usually administered initially. The usual adult oral dosage is 7.5 mg/kg every six hours (approx. 500 mg for a 70-kg adult). A maximum of 4 g should not be exceeded during a 24-hour period. Amebiasis: Adults: For acute intestinal amebiasis (acute amebic dysentery): 750 mg orally three times daily for 5 to 10 days. For amebic liver abscess: 500 mg or 750 mg orally three times daily for 5 to 10 days. Pediatric patients: 35 to 50 mg/kg/24 hours, divided into three doses, orally for 10 days.
Route of Administration: Other
Cells incubated with lethal drug (Metronidazole (MTZ)) concentration exhibit unchanged DNA profile, only about 50% of cells are positive for γH2A and lose an ability to attach to a surface after few hours of incubation. It is likely that the early reaction of cells to lethal concentration of MTZ is not primarily initiated by the reaction to DNA damage but rather by the immediate interaction of MTZ with biomolecules where activated MTZ is generated.
Substance Class Chemical
Created
by admin
on Wed Apr 02 12:06:00 GMT 2025
Edited
by admin
on Wed Apr 02 12:06:00 GMT 2025
Record UNII
8Y356BW999
Record Status Validated (UNII)
Record Version
  • Download
Name Type Language
2-hydroxy-2-[2-[2-(2-methyl-5-nitro-imidazol-1-yl)ethoxy]-2-oxo-ethyl]butanedioic acid
Preferred Name English
metronidazole citrate
Common Name English
Code System Code Type Description
FDA UNII
8Y356BW999
Created by admin on Wed Apr 02 12:06:00 GMT 2025 , Edited by admin on Wed Apr 02 12:06:00 GMT 2025
PRIMARY
PUBCHEM
165412102
Created by admin on Wed Apr 02 12:06:00 GMT 2025 , Edited by admin on Wed Apr 02 12:06:00 GMT 2025
PRIMARY
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