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Details

Stereochemistry ACHIRAL
Molecular Formula C6H9N3O3.ClH
Molecular Weight 207.615
Optical Activity NONE
Defined Stereocenters 0 / 0
E/Z Centers 0
Charge 0

SHOW SMILES / InChI
Structure of METRONIDAZOLE HYDROCHLORIDE

SMILES

Cl.CC1=NC=C(N1CCO)[N+]([O-])=O

InChI

InChIKey=FPTPAIQTXYFGJC-UHFFFAOYSA-N
InChI=1S/C6H9N3O3.ClH/c1-5-7-4-6(9(11)12)8(5)2-3-10;/h4,10H,2-3H2,1H3;1H

HIDE SMILES / InChI

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
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
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
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
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
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
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: ∞ants
sex:
food status:
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
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
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
unknown, oral
METRONIDAZOLE plasma
Homo sapiens
population: HEALTHY
age: ADULT
sex: UNKNOWN
food status: UNKNOWN
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
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
n = 1
Health Status: unhealthy
Condition: chronic depressive illness
Age Group: 58 years
Sex: F
Population Size: 1
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
n = 1
Health Status: unhealthy
Condition: extensive past medical history, including end-stage renal disease
Age Group: 62 years
Sex: M
Population Size: 1
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
n = 32
Health Status: unhealthy
Condition: advanced carcinoma of the colon or rectum
Age Group: adult
Sex: unknown
Population Size: 32
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 (mean)
Highest studied dose
Dose: 5.3 mg/m2, 3 times / week
Route: oral
Route: multiple
Dose: 5.3 mg/m2, 3 times / week
Co-administed with::
radiotherapy
Sources:
unhealthy, adult
n = 28
Health Status: unhealthy
Condition: malignant brain tumors
Age Group: adult
Sex: unknown
Population Size: 28
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
n = 1
Health Status: unhealthy
Condition: bloody stools and apnoea
Age Group: preterm newborn
Sex: F
Population Size: 1
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
n = 1
Health Status: unhealthy
Condition: chronic depressive illness
Age Group: 58 years
Sex: F
Population Size: 1
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
n = 32
Health Status: unhealthy
Condition: advanced carcinoma of the colon or rectum
Age Group: adult
Sex: unknown
Population Size: 32
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
n = 32
Health Status: unhealthy
Condition: advanced carcinoma of the colon or rectum
Age Group: adult
Sex: unknown
Population Size: 32
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
n = 32
Health Status: unhealthy
Condition: advanced carcinoma of the colon or rectum
Age Group: adult
Sex: unknown
Population Size: 32
Sources:
Central nervous system toxicity 13.7%
DLT
5.3 mg/m2 3 times / week multiple, oral (mean)
Highest studied dose
Dose: 5.3 mg/m2, 3 times / week
Route: oral
Route: multiple
Dose: 5.3 mg/m2, 3 times / week
Co-administed with::
radiotherapy
Sources:
unhealthy, adult
n = 28
Health Status: unhealthy
Condition: malignant brain tumors
Age Group: adult
Sex: unknown
Population Size: 28
Sources:
Gastrointestinal toxicity 14.5%
DLT
5.3 mg/m2 3 times / week multiple, oral (mean)
Highest studied dose
Dose: 5.3 mg/m2, 3 times / week
Route: oral
Route: multiple
Dose: 5.3 mg/m2, 3 times / week
Co-administed with::
radiotherapy
Sources:
unhealthy, adult
n = 28
Health Status: unhealthy
Condition: malignant brain tumors
Age Group: adult
Sex: unknown
Population Size: 28
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
Treatment of experimental pneumocystosis: review of 7 years of experience and development of a new system for classifying antimicrobial drugs.
1992 Sep
Acute encephalopathy associated with metronidazole therapy.
1997 Mar-Jun
Do ethanol and metronidazole interact to produce a disulfiram-like reaction?
2000 Feb
A small-molecule nitroimidazopyran drug candidate for the treatment of tuberculosis.
2000 Jun 22
Mesalamine-induced chest pain: a case report.
2000 May
A simple, efficient and inexpensive program for preventing prematurity.
2001
[Pneumatosis cystoides intestinalis: the first case in Congo].
2001 Apr-Jun
Technology evaluation: CEA-TRICOM, Therion Biologics Corp.
2001 Aug
Azole-antifungal binding to a novel cytochrome P450 from Mycobacterium tuberculosis: implications for treatment of tuberculosis.
2001 Jun 15
Metronidazole-induced encephalopathy in a uremic patient: a case report.
2001 Sep
Validation of a method for the detection and confirmation of nitroimidazoles and corresponding hydroxy metabolites in turkey and swine muscle by means of gas chromatography-negative ion chemical ionization mass spectrometry.
2001 Sep 15
[The efficacy of the Helicobacter pylori eradication in people of an advanced age].
2002
Role of P53 functionality in the genotoxicity of metronidazole and its hydroxy metabolite.
2002 Apr 25
Vaccine-based therapy directed against carcinoembryonic antigen demonstrates antitumor activity on spontaneous intestinal tumors in the absence of autoimmunity.
2002 Dec 1
[Fever and weight loss as leading symptoms of infection with giardia lamblia].
2002 Feb
Antimicrobial-induced mania (antibiomania): a review of spontaneous reports.
2002 Feb
Metronidazol as a probable cause of severe liver injury.
2002 Jan-Feb
Local antimicrobial therapy after initial periodontal treatment.
2002 Jun
Lack of disulfiram-like reaction with metronidazole and ethanol.
2002 Jun
Effectiveness of metronidazole gel on cyclosporine-induced gingival overgrowth in heart transplant patients.
2002 Mar
[Antiamebic effect of metronidazole proved in a study conducted in Cienfuegos province].
2002 May-Aug
Complete remission of Crohn's disease after high-dose cyclophosphamide and autologous stem cell transplantation.
2003 Aug
Renal papillary necrosis induced by naproxen.
2003 Aug
Metronidazole-induced encephalopathy and inferior olivary hypertrophy: lesion analysis with diffusion-weighted imaging and apparent diffusion coefficient maps.
2003 Dec
Molecular mechanisms and biological significance of CTL avidity.
2003 Jul
[Evaluation on monkeys of reactogenicity and effectiveness of the complex immunoglobulin preparation formulation].
2003 May-Jun
Diazepam as a treatment for metronidazole toxicosis in dogs: a retrospective study of 21 cases.
2003 May-Jun
Bone defects of the facial skeleton - replacement with biomaterials.
2003 Nov
Bronchospasm and laryngeal stridor as an adverse effect of oxytocin treatment.
2003 Oct
Cardiac diphtheria in a previously immunized individual.
2003 Sep
[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
Perforated appendicitis: is laparoscopy safe?
2004 Apr-Jun
TRICOM: enhanced vaccines as anticancer therapy.
2004 Aug
Nitazoxanide: a new broad spectrum antiparasitic agent.
2004 Feb
A case of clarithromycin-induced manic episode (antibiomania).
2004 Mar
Thoracic spondylitis from a mycotic (Streptococcus pneumoniae) aortic aneurysm: a case report.
2004 Sep 1
Analyses of recombinant vaccinia and fowlpox vaccine vectors expressing transgenes for two human tumor antigens and three human costimulatory molecules.
2005 Feb 15
Is operative management effective in treatment of perforated typhoid?
2005 Mar
Can antibiotics prevent preterm birth--the pro and con debate.
2005 Mar
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.
Name Type Language
METRONIDAZOLE HYDROCHLORIDE
MART.   MI   ORANGE BOOK   USAN   VANDF   WHO-DD  
USAN  
Official Name English
METRONIDAZOLE HYDROCHLORIDE [MI]
Common Name English
Metronidazole hydrochloride [WHO-DD]
Common Name English
2-Methyl-5-nitroimidazole-1-ethanol monohydrochloride
Systematic Name English
SC-32642
Code English
METRONIDAZOLE HYDROCHLORIDE [ORANGE BOOK]
Common Name English
FLAGYL I.V.
Brand Name English
METRONIDAZOLE HCL
Common Name English
1H-IMIDAZOLE-1-ETHANOL, 2-METHYL-5-NITRO-, HYDROCHLORIDE
Systematic Name English
METRONIDAZOLE HYDROCHLORIDE [USAN]
Common Name English
METRONIDAZOLE HYDROCHLORIDE [VANDF]
Common Name English
METRONIDAZOLE HYDROCHLORIDE [MART.]
Common Name English
Classification Tree Code System Code
NCI_THESAURUS C279
Created by admin on Fri Dec 15 15:19:15 GMT 2023 , Edited by admin on Fri Dec 15 15:19:15 GMT 2023
NCI_THESAURUS C784
Created by admin on Fri Dec 15 15:19:15 GMT 2023 , Edited by admin on Fri Dec 15 15:19:15 GMT 2023
Code System Code Type Description
CAS
69198-10-3
Created by admin on Fri Dec 15 15:19:14 GMT 2023 , Edited by admin on Fri Dec 15 15:19:14 GMT 2023
PRIMARY
EVMPD
SUB14570MIG
Created by admin on Fri Dec 15 15:19:14 GMT 2023 , Edited by admin on Fri Dec 15 15:19:14 GMT 2023
PRIMARY
EPA CompTox
DTXSID70219228
Created by admin on Fri Dec 15 15:19:15 GMT 2023 , Edited by admin on Fri Dec 15 15:19:15 GMT 2023
PRIMARY
NCI_THESAURUS
C48005
Created by admin on Fri Dec 15 15:19:15 GMT 2023 , Edited by admin on Fri Dec 15 15:19:15 GMT 2023
PRIMARY
RXCUI
82047
Created by admin on Fri Dec 15 15:19:15 GMT 2023 , Edited by admin on Fri Dec 15 15:19:15 GMT 2023
PRIMARY RxNorm
CHEBI
50687
Created by admin on Fri Dec 15 15:19:15 GMT 2023 , Edited by admin on Fri Dec 15 15:19:15 GMT 2023
PRIMARY
ChEMBL
CHEMBL137
Created by admin on Fri Dec 15 15:19:15 GMT 2023 , Edited by admin on Fri Dec 15 15:19:15 GMT 2023
PRIMARY
SMS_ID
100000076224
Created by admin on Fri Dec 15 15:19:15 GMT 2023 , Edited by admin on Fri Dec 15 15:19:15 GMT 2023
PRIMARY
PUBCHEM
68592
Created by admin on Fri Dec 15 15:19:15 GMT 2023 , Edited by admin on Fri Dec 15 15:19:15 GMT 2023
PRIMARY
DRUG BANK
DBSALT000362
Created by admin on Fri Dec 15 15:19:15 GMT 2023 , Edited by admin on Fri Dec 15 15:19:15 GMT 2023
PRIMARY
FDA UNII
76JC1633UF
Created by admin on Fri Dec 15 15:19:15 GMT 2023 , Edited by admin on Fri Dec 15 15:19:15 GMT 2023
PRIMARY
MERCK INDEX
m7506
Created by admin on Fri Dec 15 15:19:15 GMT 2023 , Edited by admin on Fri Dec 15 15:19:15 GMT 2023
PRIMARY Merck Index