WordNet sense 1 (that stimulates):

stimulant

WordNet sense 2 (capable of arousing or accelerating physiological or psychological activity or response by a chemical agent):

stimulative

WordNet sense 3 (causing quivering or shivering as by cold or fear or electric shock):

thrilling

WordNet sense 4 (capable of arousing enthusiasm or excitement):

stirring

WordNet sense 5 (engagingly stimulating or provocative):

piquant

WordNet sense 6 (stimulating interest and discussion):

exciting

WordNet sense 7 (making lively and cheerful):

exhilarating

WordNet sense 8 (imparting strength and vitality):

invigorating