clemastine
noun
clem·as·tine
| \ ˈklem-ə-ˌstēn
\
\
Medical Definition of clemastine
: an antihistamine drug administered orally in the form of its fumarate C21H26ClNO·C4H4O4 to relieve the symptoms of hay fever and the common cold
… oral antihistamines, such as chlorpheniramine and clemastine, reduce sneezing and, to a lesser extent, rhinorrhea, probably because of their anticholinergic effects, but they are often associated with excess sedation.— Frederick G. Hayden, Scientific American Medicine Bulletin, March 1997