Otilonium bromide is an antimuscarinic.

(?)-Nicotine is the dominant form of the natural alkaloid nicotine. It acts as an agonist of neuronal nicotinic acetylcholine receptors (nAChRs) and possesses addictive and teratogenic properties. (?)-(S)-Nicotine is significantly more active at binding nAChRs compared to the (+)-(R) antipode thus nicotine is typically synthesized as (?)-(S)-nicotine with only 0.2-1% of the (+)-(R) isomer present.

Proxyphylline is a dual of adenosine A1/A2a receptor inhibitor and phosphodiesterase (PDE) inhibitor. Proxyphylline acts as a cardiac stimulant vasodilator and bronchodilator.