Exacerbation of symptoms due to diltiazem in a patient with Lambert-Eaton myasthenic myopathic syndrome.

A 65-year old man on treatment for ischaemic heart disease presented with a history of pain and weakness of all four limbs and dry mouth. He had clinical and neurophysiological features of Lambert-Eaton myasthenic syndrome. His symptoms improved after withdrawal of diltiazem, although neurophysiological changes remained even after 3 months.