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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 of METHIMAZOLE

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

Description

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 TargetPharmacologyConditionPotency

Conditions

ConditionModalityTargetsHighest PhaseProduct
Primary
Tapazole

Cmax

ValueDoseCo-administeredAnalytePopulation
248 ng/mL
10 mg single, oral
METHIMAZOLE plasma
Homo sapiens
213 ng/mL
0.17 mg/kg bw single, oral
METHIMAZOLE serum
Homo sapiens
299 ng/mL
0.21 mg/kg bw single, oral
METHIMAZOLE serum
Homo sapiens
380 ng/mL
0.3 mg/kg bw single, oral
METHIMAZOLE serum
Homo sapiens
803 ng/mL
0.57 mg/kg bw single, oral
METHIMAZOLE serum
Homo sapiens

AUC

ValueDoseCo-administeredAnalytePopulation
1661 μg × h/L
10 mg single, oral
METHIMAZOLE plasma
Homo sapiens
2657 ng × h/mL
0.17 mg/kg bw single, oral
METHIMAZOLE serum
Homo sapiens
3228 ng × h/mL
0.21 mg/kg bw single, oral
METHIMAZOLE serum
Homo sapiens
4773 ng × h/mL
0.3 mg/kg bw single, oral
METHIMAZOLE serum
Homo sapiens
7136 ng × h/mL
0.57 mg/kg bw single, oral
METHIMAZOLE serum
Homo sapiens
1833 μg × h/L
10 mg single, intravenous
METHIMAZOLE plasma
Homo sapiens
2450 ng × h/mL
0.16 mg/kg bw single, intravenous
METHIMAZOLE serum
Homo sapiens
2922 ng × h/mL
0.21 mg/kg bw single, intravenous
METHIMAZOLE serum
Homo sapiens

T1/2

ValueDoseCo-administeredAnalytePopulation
5.3 h
10 mg single, oral
METHIMAZOLE plasma
Homo sapiens
14 h
0.17 mg/kg bw single, oral
METHIMAZOLE serum
Homo sapiens
14 h
0.21 mg/kg bw single, oral
METHIMAZOLE serum
Homo sapiens
20.1 h
0.3 mg/kg bw single, oral
METHIMAZOLE serum
Homo sapiens
15 h
0.57 mg/kg bw single, oral
METHIMAZOLE serum
Homo sapiens
5.3 h
10 mg single, intravenous
METHIMAZOLE plasma
Homo sapiens
20.7 h
0.16 mg/kg bw single, intravenous
METHIMAZOLE serum
Homo sapiens
18.5 h
0.21 mg/kg bw single, intravenous
METHIMAZOLE serum
Homo sapiens

Overview

OverviewOther

Other InhibitorOther SubstrateOther Inducer






Drug as perpetrator​

PubMed

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