Scopolamine alleviates involuntary lingual movements: tardive dyskinesia or dystonia?

Cholinergic hypofunction was believed to be associated with the pathogenesis of tardive dyskinesia, and therefore, anticholinergic treatment might exacerbate the condition. We describe herein a middle-aged male with feeble chewing movements, involuntary rolling motions of the tongue, and abnormally tightened cheeks which developed after consuming different psychotropic medications. These symptoms did not improve after routine treatment for tardive dyskinesia, but responded well to anticholinergic agents, such as scopolamine and benzhexol hydrochloride. This case extended our understanding of the complexity of extrapyramidal effects and their pharmacologic management.