caffeine drug pathway caffeine pharmacodynamics pathway 2015-12-07T08:36:29Z PW:0002319 The pathway of caffeine-target interaction and of the biochemical or physiological responses to drug. Caffeine is an antagonist of adenosine receptors of all types. As such, it stimulates vasomotor and respiratory centers and also promotes neurotransmitter release. Genetic variations can cause differences in the response of the organism to the drug. pathway vpetri