METHIMAZOLE

Details

Stereochemistry	ACHIRAL
Molecular Formula	C4H6N2S
Molecular Weight	114.169
Optical Activity	NONE
Defined Stereocenters	0 / 0
E/Z Centers	0
Charge	0

SHOW SMILES / InChI

Structure Search

SMILES

CN1C=CNC1=S

InChI

InChIKey=PMRYVIKBURPHAH-UHFFFAOYSA-N

InChI=1S/C4H6N2S/c1-6-3-2-5-4(6)7/h2-3H,1H3,(H,5,7)

HIDE SMILES / InChI

Molecular Formula	C4H6N2S
Molecular Weight	114.169
Charge	0
Count

Stereochemistry	ACHIRAL
Additional Stereochemistry	No
Defined Stereocenters	0 / 0
E/Z Centers	0
Optical Activity	NONE

Description
Sources: http://www.drugbank.ca/drugs/DB00763
Curator's Comment: Description was created based on several sources, including https://www.drugs.com/cdi/methimazole.html

Methimazole (also known as Tapazole or Thiamazole or MMI) is an antithyroid drug. Methimazole binds to thyroid peroxidase and thereby inhibits the conversion of iodide to iodine. Thyroid peroxidase normally converts iodide to iodine (via hydrogen peroxide as a cofactor) and also catalyzes the incorporation of the resulting iodide molecule onto both the 3 and/or 5 positions of the phenol rings of tyrosines found in thyroglobulin. Thyroglobulin is degraded to produce thyroxine (T4) and tri-iodothyronine (T3), which are the main hormones produced by the thyroid gland. So methimazole effectively inhibits the production of new thyroid hormones. Methimazole is used for the treatment of hyperthyroidism, goiter, Graves disease and psoriasis.

Originator

Approval Year

Targets

Primary Target	Pharmacology	Condition	Potency
Thyroid peroxidase 11 Target ID: CHEMBL1839 Sources: http://www.drugbank.ca/drugs/DB00763	Inhibitor 8504

Conditions

Condition	Modality	Targets	Highest Phase	Product
Hyperthyroidism 13 Sources: http://www.accessdata.fda.gov/drugsatfda_docs/label/2012/040320s005lbl.pdf	Primary		Approved 8583	Tapazole Approved Use TAPAZOLE is indicated: In patients with Graves’ disease with hyperthyroidism or toxic multinodular goiter for whom surgery or radioactive iodine therapy is not an appropriate treatment option. To ameliorate symptoms of hyperthyroidism in preparation for thyroidectomy or radioactive iodine therapy. Launch Date 1950

C_max

Value	Dose	Analyte	Population
248 ng/mL EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/4042519/	10 mg single, oral dose: 10 mg route of administration: Oral experiment type: SINGLE co-administered:	METHIMAZOLE plasma	Homo sapiens population: HEALTHY age: ADULT sex: FEMALE / MALE food status: FASTED
213 ng/mL EXPERIMENT https://www.jstage.jst.go.jp/article/endocrj1954/33/5/33_5_605/_pdf	0.17 mg/kg bw single, oral dose: 0.17 mg/kg bw route of administration: Oral experiment type: SINGLE co-administered:	METHIMAZOLE serum	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: FED
299 ng/mL EXPERIMENT https://www.jstage.jst.go.jp/article/endocrj1954/33/5/33_5_605/_pdf	0.21 mg/kg bw single, oral dose: 0.21 mg/kg bw route of administration: Oral experiment type: SINGLE co-administered:	METHIMAZOLE serum	Homo sapiens population: UNHEALTHY age: ADULT sex: FEMALE / MALE food status: FED
380 ng/mL EXPERIMENT https://www.jstage.jst.go.jp/article/endocrj1954/33/5/33_5_605/_pdf	0.3 mg/kg bw single, oral dose: 0.3 mg/kg bw route of administration: Oral experiment type: SINGLE co-administered:	METHIMAZOLE serum	Homo sapiens population: UNHEALTHY age: ADULT sex: FEMALE / MALE food status: FED
803 ng/mL EXPERIMENT https://www.jstage.jst.go.jp/article/endocrj1954/33/5/33_5_605/_pdf	0.57 mg/kg bw single, oral dose: 0.57 mg/kg bw route of administration: Oral experiment type: SINGLE co-administered:	METHIMAZOLE serum	Homo sapiens population: UNHEALTHY age: ADULT sex: FEMALE / MALE food status: FED

AUC

Value	Dose	Analyte	Population
1833 μg × h/L EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/4042519/	10 mg single, intravenous dose: 10 mg route of administration: Intravenous experiment type: SINGLE co-administered:	METHIMAZOLE plasma	Homo sapiens population: HEALTHY age: ADULT sex: FEMALE / MALE food status: FASTED
1661 μg × h/L EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/4042519/	10 mg single, oral dose: 10 mg route of administration: Oral experiment type: SINGLE co-administered:	METHIMAZOLE plasma	Homo sapiens population: HEALTHY age: ADULT sex: FEMALE / MALE food status: FASTED
2450 ng × h/mL EXPERIMENT https://www.jstage.jst.go.jp/article/endocrj1954/33/5/33_5_605/_pdf	0.16 mg/kg bw single, intravenous dose: 0.16 mg/kg bw route of administration: Intravenous experiment type: SINGLE co-administered:	METHIMAZOLE serum	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: FED
2922 ng × h/mL EXPERIMENT https://www.jstage.jst.go.jp/article/endocrj1954/33/5/33_5_605/_pdf	0.21 mg/kg bw single, intravenous dose: 0.21 mg/kg bw route of administration: Intravenous experiment type: SINGLE co-administered:	METHIMAZOLE serum	Homo sapiens population: UNHEALTHY age: ADULT sex: FEMALE / MALE food status: FED
2657 ng × h/mL EXPERIMENT https://www.jstage.jst.go.jp/article/endocrj1954/33/5/33_5_605/_pdf	0.17 mg/kg bw single, oral dose: 0.17 mg/kg bw route of administration: Oral experiment type: SINGLE co-administered:	METHIMAZOLE serum	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: FED
3228 ng × h/mL EXPERIMENT https://www.jstage.jst.go.jp/article/endocrj1954/33/5/33_5_605/_pdf	0.21 mg/kg bw single, oral dose: 0.21 mg/kg bw route of administration: Oral experiment type: SINGLE co-administered:	METHIMAZOLE serum	Homo sapiens population: UNHEALTHY age: ADULT sex: FEMALE / MALE food status: FED
4773 ng × h/mL EXPERIMENT https://www.jstage.jst.go.jp/article/endocrj1954/33/5/33_5_605/_pdf	0.3 mg/kg bw single, oral dose: 0.3 mg/kg bw route of administration: Oral experiment type: SINGLE co-administered:	METHIMAZOLE serum	Homo sapiens population: UNHEALTHY age: ADULT sex: FEMALE / MALE food status: FED
7136 ng × h/mL EXPERIMENT https://www.jstage.jst.go.jp/article/endocrj1954/33/5/33_5_605/_pdf	0.57 mg/kg bw single, oral dose: 0.57 mg/kg bw route of administration: Oral experiment type: SINGLE co-administered:	METHIMAZOLE serum	Homo sapiens population: UNHEALTHY age: ADULT sex: FEMALE / MALE food status: FED

T_1/2

Value	Dose	Analyte	Population
5.3 h EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/4042519/	10 mg single, intravenous dose: 10 mg route of administration: Intravenous experiment type: SINGLE co-administered:	METHIMAZOLE plasma	Homo sapiens population: HEALTHY age: ADULT sex: FEMALE / MALE food status: FASTED
5.3 h EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/4042519/	10 mg single, oral dose: 10 mg route of administration: Oral experiment type: SINGLE co-administered:	METHIMAZOLE plasma	Homo sapiens population: HEALTHY age: ADULT sex: FEMALE / MALE food status: FASTED
20.7 h EXPERIMENT https://www.jstage.jst.go.jp/article/endocrj1954/33/5/33_5_605/_pdf	0.16 mg/kg bw single, intravenous dose: 0.16 mg/kg bw route of administration: Intravenous experiment type: SINGLE co-administered:	METHIMAZOLE serum	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: FED
18.5 h EXPERIMENT https://www.jstage.jst.go.jp/article/endocrj1954/33/5/33_5_605/_pdf	0.21 mg/kg bw single, intravenous dose: 0.21 mg/kg bw route of administration: Intravenous experiment type: SINGLE co-administered:	METHIMAZOLE serum	Homo sapiens population: UNHEALTHY age: ADULT sex: FEMALE / MALE food status: FED
14 h EXPERIMENT https://www.jstage.jst.go.jp/article/endocrj1954/33/5/33_5_605/_pdf	0.17 mg/kg bw single, oral dose: 0.17 mg/kg bw route of administration: Oral experiment type: SINGLE co-administered:	METHIMAZOLE serum	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: FED
14 h EXPERIMENT https://www.jstage.jst.go.jp/article/endocrj1954/33/5/33_5_605/_pdf	0.21 mg/kg bw single, oral dose: 0.21 mg/kg bw route of administration: Oral experiment type: SINGLE co-administered:	METHIMAZOLE serum	Homo sapiens population: UNHEALTHY age: ADULT sex: FEMALE / MALE food status: FED
20.1 h EXPERIMENT https://www.jstage.jst.go.jp/article/endocrj1954/33/5/33_5_605/_pdf	0.3 mg/kg bw single, oral dose: 0.3 mg/kg bw route of administration: Oral experiment type: SINGLE co-administered:	METHIMAZOLE serum	Homo sapiens population: UNHEALTHY age: ADULT sex: FEMALE / MALE food status: FED
15 h EXPERIMENT https://www.jstage.jst.go.jp/article/endocrj1954/33/5/33_5_605/_pdf	0.57 mg/kg bw single, oral dose: 0.57 mg/kg bw route of administration: Oral experiment type: SINGLE co-administered:	METHIMAZOLE serum	Homo sapiens population: UNHEALTHY age: ADULT sex: FEMALE / MALE food status: FED

Overview

CYP3A4	CYP2C9	CYP2D6	hERG
inhibitor 2252	inhibitor 2438	inhibitor 2507

OverviewOther

Other Inhibitor	Other Substrate	Other Inducer
OCTN1 32 CYP2E1 1060 CYP1A2 2153 CYP2C19 2057 CYP2A6 879 CYP2B6 926

Drug as perpetrator

Target	Modality	Activity
CYP3A4 2633	inhibitor 4027 Sources: https://bioinformatics.charite.de/transformer/index.php?site=fullinfo&cname=000060560	major [IC50 14 uM]
CYP2A6 911	inhibitor 4027 Sources: https://bioinformatics.charite.de/transformer/index.php?site=fullinfo&cname=000060560	no [IC50 >/=1000 uM]
CYP2C19 2141	inhibitor 4027 Sources: https://bioinformatics.charite.de/transformer/index.php?site=fullinfo&cname=000060560	no [IC50 >/=1000 uM]
CYP2D6 2546	inhibitor 4027 Sources: https://bioinformatics.charite.de/transformer/index.php?site=fullinfo&cname=000060560	no [IC50 >/=1000 uM]
CYP2E1 1146	inhibitor 4027 Sources: https://bioinformatics.charite.de/transformer/index.php?site=fullinfo&cname=000060560	no [IC50 >/=1000 uM]
CYP2B6 1160	inhibitor 4027 Sources: https://bioinformatics.charite.de/transformer/index.php?site=fullinfo&cname=000060560	weak [IC50 100 uM]
CYP2C9 2497	inhibitor 4027 Sources: https://bioinformatics.charite.de/transformer/index.php?site=fullinfo&cname=000060560	weak [IC50 100 uM]
CYP1A2 2333	inhibitor 4027 Sources: https://bioinformatics.charite.de/transformer/index.php?site=fullinfo&cname=000060560	weak [Inhibition 50 uM]
OCTN1 32	inhibitor 4027 Sources: http://transportal.compbio.ucsf.edu/compounds/methimazole/	weak [Ki 7500 uM]

Sourcing

Vendor/Aggregator	ID	URL
ChEBI	CHEBI:50673	https://www.ebi.ac.uk/chebi/searchId.do?chebiId=CHEBI:50673
ChemicalBook	CB9220870	https://www.chemicalbook.com/ChemicalProductProperty_EN_CB9220870
eMolecules	1971965	https://www.emolecules.com/cgi-bin/more?vid=1971965
eMolecules	496094	https://www.emolecules.com/cgi-bin/more?vid=496094
MolPort	MolPort-000-563-838	https://www.molport.com/shop/molecule-link/MolPort-000-563-838
MolPort	MolPort-002-508-019	https://www.molport.com/shop/molecule-link/MolPort-002-508-019
Selleck Chemicals	Methimazole(Tapazole)	http://www.selleckchem.com/products/Methimazole(Tapazole).html
ZINC	ZINC000001187543	http://zinc15.docking.org/substances/ZINC000001187543

PubMed

Title	Date	PubMed
Severe embryopathy and exposure to methimazole in early pregnancy.	2002-02	11836348
Cell necrosis and apoptosis are differentially regulated during goitre development and iodine-induced involution.	2002-02	11834455
Influence of hypothyroidism on circulating concentrations and liver expression of IGF-binding proteins mRNA from neonatal and adult rats.	2002-02	11834454
Clinical features and outcomes in children with antineutrophil cytoplasmic autoantibody-positive glomerulonephritis associated with propylthiouracil treatment.	2002-02	11805173
Streptozotocin diabetes protects against arrhythmias in rat isolated hearts: role of hypothyroidism.	2002-01-25	11821037
Polarization IR spectra of model crystals containing cyclic N-H...S bonded dimers: 2-mercaptothiazoline and 2-mercapto-1-methylimidazole.	2002-01-15	11808728
Subclinical hyperthyroidism.	2002-01-03	11778009
Depigmentation of brown Guinea pig skin by topical application of methimazole.	2002-01	11851896
Severe and mild neonatal hypothyroidism mediate opposite effects on Leydig cells of rats.	2002-01	11838725
Teratogen update: antithyroid drugs-methimazole, carbimazole, and propylthiouracil.	2002-01	11835230
Methimazole-induced asthma?	2002-01	11796476
Identification of active flavin-containing monooxygenase isoform 2 in human lung and characterization of expressed protein.	2002-01	11744609
Impact of hyperthyroidism and its correction on vascular reactivity in humans.	2001-12-18	11748103
Protracted expression of serotonin transporter and altered thalamocortical projections in the barrelfield of hypothyroid rats.	2001-12	11860492
Hypothyroidism induces type I iodothyronine deiodinase expression in tilapia liver.	2001-12	11742517
Effects of neonatal hypothyroidism on the expressions of growth cone proteins and axon guidance molecules related genes in the hippocampus.	2001-11-26	11694350
Apoptosis, necrosis, and cell proliferation induced by S-(1,2-dichlorovinyl)-L-cysteine in primary cultures of human proximal tubular cells.	2001-11-15	11708895
[Graves-Basedow disease associated with unusual variation of thyroid papillary carcinoma: a clinical case].	2001-11-02	11688359
Methimazole-induced pulmonary hemorrhage associated with antimyeloperoxidase-antineutrophil cytoplasmic antibody: a case report.	2001-11	11802538
Hyperemesis gravidarum associated with thyrotoxicosis and a past history of an eating disorder.	2001-11	11789755
Influence of nicotinamide on the radiosensitivity of normal and goitrous thyroid in the rat.	2001-11	11762708
Adverse effects of prenatal methimazole exposure.	2001-11	11745832
Effect of eicosapentaenoic acid ethyl ester on hypothyroid function.	2001-11	11691645
Methimazole as an antioxidant and immunomodulator in thyroid cells: mechanisms involving interferon-gamma signaling and H(2)O(2) scavenging.	2001-11	11641425
Radioiodine and Graves' ophthalmopathy reconsidered.	2001-11	11606880
Different role of insulin in GLUT-1 and -4 regulation in heart and skeletal muscle during perinatal hypothyroidism.	2001-11	11595665
The effect of methimazole on thyroid uptake of pertechnetate and radioiodine in normal cats.	2001-10-27	11678569
Thyroid hormones modify susceptibility to lidocaine-kindling in rats.	2001-10-19	11712661
Selective effect of hypothyroidism on expression of myelin markers during development.	2001-10-15	11592121
Neonatal hyperthyroidism in infants of mothers previously thyroidectomized due to Graves' disease.	2001-10-11	11592578
Dermatomyositis and Graves' disease.	2001-10-03	11579725
Severe myocardial ischemia following hormone replacement in two cases of hypothyroidism with normal coronary arteriogram.	2001-10	11789561
Risk of torsades de pointes from oral erythromycin with concomitant carbimazole (methimazole) administration.	2001-10	11707056
Suppression of serum TSH by Graves' Ig: evidence for a functional pituitary TSH receptor.	2001-10	11600546
Use of oral cholecystographic agents in the treatment of amiodarone-induced hyperthyroidism.	2001-10	11600529
Antithyroid drugs as a factor influencing the outcome of radioiodine therapy in Graves' disease and toxic nodular goitre?	2001-09	11585295
Effect of losartan on sodium appetite of hypothyroid rats subjected to water and sodium depletion and water, sodium and food deprivation.	2001-09	11571491
Thyroid hormone regulates oxidative phosphorylation in the cerebral cortex and striatum of neonatal rats.	2001-09	11553679
Ca(2+)/nicotinamide adenine dinucleotide phosphate-dependent H(2)O(2) generation is inhibited by iodide in human thyroids.	2001-09	11549671
Clinical practice. Subclinical hyperthyroidism.	2001-08-16	11519506
[Long-term results of ultrasound-guided ethanol injections in patients with autonomous thyroid nodules and hyperthyroidism].	2001-08-15	11560045
Estimation of antithyroid drug dose in Graves' disease: value of quantification of thyroid blood flow with color duplex sonography.	2001-08	11527601
A case of thyrotoxicosis with pancytopenia.	2001-06	11523911
[Effect of thyroxine upon prevention of recurrence of Graves' disease treated with antithyroid drugs].	2001-03-10	11798886
Sequencing, expression, and characterization of cDNA expressed flavin-containing monooxygenase 2 from mouse.	2001	11835629
Body, heart, thyroid gland and skeletal muscle weight changes in rats with altered thyroid status.	2001	11829324
Drug-induced congenital defects: strategies to reduce the incidence.	2001	11735646
Role of thyroid hormones in the maturation and organisation of rat barrel cortex.	2001	11718994
[Ablative therapy for immune hyperthyroidism in patients with ophthalmopathy].	2001	11593892
The activity of antioxidant enzymes and the content of uncoupling protein-1 in the brown adipose tissue of hypothyroid rats: comparison with effects of iopanoic acid.	2001	11521740

Patents

Sample Use Guides

In Vivo Use Guide

Usual Adult Dose for Hyperthyroidism Initial: Mild hyperthyroidism: 5 mg orally every 8 hours. Moderately severe hyperthyroidism: 10 mg orally every 8 hours (up to 40 mg per day). Severe hyperthyroidism: 20 mg orally every 8 hours. Maintenance: 5 to 15 mg orally daily.

Route of Administration: Oral

In Vitro Use Guide

Methimazole had the strongest antioxidative properties in human erythrocytes at the concentration level of 0.5 mM

Substance Class	Chemical Created by `admin` on `Mon Mar 31 17:45:00 GMT 2025` Edited by `admin` on `Mon Mar 31 17:45:00 GMT 2025`
Record UNII	554Z48XN5E
Record Status	`Validated (UNII)`
Record Version

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Name

Type

Language

THIAMAZOLE

Preferred Name

English

METHIMAZOLE

Common Name

English

1-Methylimidazole-2-thiol

Systematic Name

English

METHIMAZOLE [MI]

Common Name

English

METHIMAZOLE [VANDF]

Common Name

English

METHIMAZOLE [ORANGE BOOK]

Common Name

English

METHIMAZOLE [USP-RS]

Common Name

English

NSC-38608

Code

English

2H-IMIDAZOLE-2-THIONE, 1,3-DIHYDRO-1-METHYL-

Systematic Name

English

TAPAZOLE

Brand Name

English

THIAMAZOLE [MART.]

Common Name

English

THIAMAZOLE [EP MONOGRAPH]

Common Name

English

Thiamazole [WHO-DD]

Common Name

English

thiamazole [INN]

Common Name

English

MERCAPTIZOLE

Brand Name

English

METHIMAZOLE [USP MONOGRAPH]

Common Name

English

METHIMAZOLE [HSDB]

Common Name

English

METHIMAZOLE [IARC]

Common Name

English

THIAMAZOLE [JAN]

Common Name

English

Classification Tree Code System Code

IARC

Methimazole

LIVERTOX

NBK548406