A catecholamine in which the 2-aminoethyl group is substituted with a hydroxy group at C-1 and a methyl group at C-2, with configurations 1R,2S. A metabolite of alpha-methyl-L-dopa, it is an alpha2-adrenergic agonist and acts as a topical nasal decongestant and vasoconstrictor, most often used in dentistry.