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Details

Stereochemistry ABSOLUTE
Molecular Formula C21H26ClNO.C4H4O4
Molecular Weight 459.962
Optical Activity UNSPECIFIED
Defined Stereocenters 2 / 2
E/Z Centers 1
Charge 0

SHOW SMILES / InChI
Structure of CLEMASTINE FUMARATE

SMILES

OC(=O)\C=C\C(O)=O.CN1CCC[C@@H]1CCO[C@](C)(C2=CC=CC=C2)C3=CC=C(Cl)C=C3

InChI

InChIKey=PMGQWSIVQFOFOQ-YKVZVUFRSA-N
InChI=1S/C21H26ClNO.C4H4O4/c1-21(17-7-4-3-5-8-17,18-10-12-19(22)13-11-18)24-16-14-20-9-6-15-23(20)2;5-3(6)1-2-4(7)8/h3-5,7-8,10-13,20H,6,9,14-16H2,1-2H3;1-2H,(H,5,6)(H,7,8)/b;2-1+/t20-,21-;/m1./s1

HIDE SMILES / InChI

Molecular Formula C4H4O4
Molecular Weight 116.0722
Charge 0
Count
MOL RATIO 1 MOL RATIO (average)
Stereochemistry ACHIRAL
Additional Stereochemistry No
Defined Stereocenters 0 / 0
E/Z Centers 1
Optical Activity NONE

Molecular Formula C21H26ClNO
Molecular Weight 343.89
Charge 0
Count
MOL RATIO 1 MOL RATIO (average)
Stereochemistry ABSOLUTE
Additional Stereochemistry No
Defined Stereocenters 2 / 2
E/Z Centers 0
Optical Activity UNSPECIFIED

Description

Clemastine is an antihistamine with anticholinergic (drying) and sedative side effects. Clemastine is a selective histamine H1 antagonist and binds to the histamine H1 receptor. This blocks the action of endogenous histamine, which subsequently leads to temporary relief of the negative symptoms brought on by histamine. It is used for the relief of symptoms associated with allergic rhinitis such as sneezing, rhinorrhea, pruritus and acrimation. Also for the management of mild, uncomplicated allergic skin manifestations of urticaria and angioedema. Used as self-medication for temporary relief of symptoms associated with the common cold.

CNS Activity

Originator

Approval Year

Targets

Primary TargetPharmacologyConditionPotency
0.4 µM [IC50]
12.0 nM [IC50]
2.0 µM [Ki]

Conditions

ConditionModalityTargetsHighest PhaseProduct
Primary
CLEMASTINE
Primary
CLEMASTINE

Cmax

ValueDoseCo-administeredAnalytePopulation
0.7 ng/mL
3 mg single, oral
CLEMASTINE plasma
Homo sapiens
650 pg/mL
0.5 mg single, oral
CLEMASTINE plasma
Homo sapiens
1010 pg/mL
1 mg single, oral
CLEMASTINE plasma
Homo sapiens

AUC

ValueDoseCo-administeredAnalytePopulation
4.2 ng × h/mL
3 mg single, oral
CLEMASTINE plasma
Homo sapiens
15529 pg × h/mL
0.5 mg single, oral
CLEMASTINE plasma
Homo sapiens
26230 pg × h/mL
1 mg single, oral
CLEMASTINE plasma
Homo sapiens

T1/2

ValueDoseCo-administeredAnalytePopulation
8 h
3 mg single, oral
CLEMASTINE plasma
Homo sapiens
17.28 h
0.5 mg single, oral
CLEMASTINE plasma
Homo sapiens
23.94 h
1 mg single, oral
CLEMASTINE plasma
Homo sapiens

Doses

AEs

Overview

CYP3A4CYP2C9CYP2D6hERG


OverviewOther

Other InhibitorOther SubstrateOther Inducer

Drug as perpetrator​

Tox targets

PubMed

Sample Use Guides

In Vivo Use Guide
Usual Adult Dose for Allergic Rhinitis Initial dose: 1.34 mg orally twice a day. Dosage may be increased as required, but not to exceed 2.68 mg orally 3 times a day.
Route of Administration: Oral
In Vitro Use Guide
IHERG tails at -40 mV following depolarizing pulses to +20 mV were inhibited by clemastine with an IC50 value of 12 nM in HEK 293 cells
Substance Class Chemical
Record UNII
19259EGQ3D
Record Status Validated (UNII)
Record Version