Summary Background Idiopathic hyperhidrosis may be a disabling condition causing emotional stress and negative impact on a patient's quality of life. Oral anticholinergics are one of the treatments available. There are few published data on the use of the anticholinergic drug glycopyrronium bromide (glycopyrrolate) given orally in the treatment of hyperhidrosis. Objectives To report a retrospective analysis describing the treatment responses, doses and side-effects of oral glycopyrrolate in the treatment of idiopathic hyperhidrosis. Methods Review of case notes in a series of 24 patients, nine with generalized and 15 with localized hyperhidrosis. Results Fifteen of 19 evaluable patients (79%) responded to oral glycopyrrolate. However, treatment was limited by side-effects in around one third of patients. Conclusions A prospective clinical study to compare the efficacy and side-effects of oral anticholinergics is warranted.