Both prostigmine methyl sulfate and quinine are known to influence the effects of stimulation of cholinergic nerves. Prostigmine methyl sulfate increases these effects, and has actions that closely resemble those of physostigmine. It depresses the activity of choline esterase (McGeorge1), antagonizes the effects of curare (Briscoe2), and has effects on various organs that are similar to those produced by cholinergic nerve stimulation (Aeschlimann and Reinert3). On the other hand, quinine reduces the effects of cholinergic nerve stimulation on striated muscle (Harvey4) and the salivary glands (Stavraky5) and decreases the effects of acetylbetamethylcholine (Starr6) and of vagal stimulation on the heart (Lewis, Drury, Iliescu and Wedd7 and Nathanson8).
Recently, both drugs have found a useful place in the management of patients with certain muscular disorders. In myasthenia gravis, muscular weakness and fatigability often are improved promptly, although only temporarily, by the administration of