8-Cyclopentyl-13-dimethylxanthine (8-Cyclopentyltheophylline 8-CPT CPX) is a drug which acts as a potent and selective antagonist for the adenosine receptors with some selectivity for the A1 receptor subtype as well as a non-selective phosphodiesterase inhibitor. It has stimulant effects in animals with slightly higher potency than caffeine.
