SCH-58261 is a drug which acts as a potent and selective antagonist for the adenosine receptor A<sub>2A</sub>, with more than 50x selectivity for A<sub>2A</sub> over other adenosine receptors. It has been used to investigate the mechanism of action of caffeine, which is a mixed A<sub>1</sub> / A<sub>2A</sub> antagonist, and has shown that the A<sub>2A</sub> receptor is primarily responsible for the stimulant and ergogenic effects of caffeine, but blockade of both A<sub>1</sub> and A<sub>2A</sub> receptors is required to accurately replicate caffeine's effects in animals. SCH-58261 has also shown antidepressant, nootropic and neuroprotective effects in a variety of animal models, and has been investigated as a possible treatment for Parkinson's disease.