Clemastine

Clemastine
Clinical data
AHFS/Drugs.comMonograph
MedlinePlusa682542
Routes of
administration
Oral
ATC code
Legal status
Legal status
Pharmacokinetic data
Bioavailability39.2%
MetabolismHepatic
Elimination half-life21.3 hours
ExcretionRenal
Identifiers
  • (2R)-2-{2-[(1R)-1-(4-chlorophenyl)-1-phenylethoxy]ethyl}-1-methylpyrrolidine
CAS Number
PubChem CID
IUPHAR/BPS
DrugBank
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
CompTox Dashboard (EPA)
Chemical and physical data
FormulaC21H26ClNO
Molar mass343.90 g·mol−1
3D model (JSmol)
  • Clc1ccc(cc1)[C@](OCC[C@@H]2N(C)CCC2)(c3ccccc3)C
  • InChI=1S/C21H26ClNO/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/h3-5,7-8,10-13,20H,6,9,14-16H2,1-2H3/t20-,21-/m1/s1 checkY
  • Key:YNNUSGIPVFPVBX-NHCUHLMSSA-N checkY
  (verify)

Clemastine, also known as meclastin, is a first-generation H1 histamine antagonist (antihistamine) with anticholinergic properties (drying) and sedative side effects.[1] Like all first-generation antihistamines, it is sedating.[2][3]

Patented in 1960, it came into medical use in 1967.[4]

  1. ^ "Clemastine". DrugBank.com.
  2. ^ "Perspectives on Second-Generation OTC Antihistamines". Pharmacy Times. 2012-03-30. Archived from the original on 2012-05-01.
  3. ^ Krouse JH (April 2008). "Allergic rhinitis--current pharmacotherapy". Otolaryngologic Clinics of North America. 41 (2): 347–58, vii. doi:10.1016/j.otc.2007.11.014. PMID 18328373.
  4. ^ Fischer J, Ganellin CR (2006). Analogue-based Drug Discovery. John Wiley & Sons. p. 547. ISBN 9783527607495.