\-i-ˈfed-rən, British also -ˈef-ə-drən\
: a crystalline alkaloid C10H15NO that is isomeric with ephedrine and is administered chiefly in the form of its hydrochloride C10H15NO·HCl or sulfate (C10H15NO)2·H2SO4 especially to relieve nasal congestion
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