Antimuscarinic itsef signify anticholinergic property. drugs prescribed for treatment of parkinsonism as well as drug induced parkinsonism should possess anticholinergic property to counter compensetary cholinergic overactivity in parkinsonism which is due to dopaminergic hypoactivity.
As suggested by many RG peers the brief pharmacology of procyclidine is it has an atropine-like action on parasympathetic-innervated peripheral structures including smooth muscle. It's antispasmodic effects are thought to be related to the blockage of central cholinergic receptors M1, M2 and M4. It is used to treat symptomatic Parkinsonism and extrapyramidal dysfunction caused by antipsychotic agents.