benztropine

:  a anticholinergic drug administered in the form of its mesylate C₂₁H₂₅NO·CH₄O₃S especially to treat the symptoms of Parkinson's disease (such as tremors, spasms, or muscle weakness) or similar symptoms caused as side effects of other drugs (such as phenothiazine derivatives) … an anticholinergic agent, such as benztropine, that restores the balance between dopamine and acetylcholine and reestablishes the normal inhibitory outflow from the basal ganglia.—Raphael J. Leo and Simrita Singh, The Psychiatric Times, 1 Dec. 2007