Dehydroepiandrosterone (DHEA) and glucocorticoids are steroid hormones synthesised in the adrenal cortex. Administration of DHEA, its sulphate derivative, DHEAS, and more controversially dexamethasone (DEX), a synthetic glucocorticoid, have beneficial effects in diabetic animals. Cultivating BRIN-BD11 cells for 3 days with either DHEAS (30 muM) or DEX (100 nM), reduced total cell number and reduced cell viability and cellular insulin content. DHEAS-treated cells had poor glucose responsiveness and regulated insulin release, coupled with reduced basal insulin release. In contrast, DEX-treated cells lacked responsiveness to glucose and membrane depolarisation, and both protein kinase A (PKA) and protein kinase C (PKC) secretory pathways were desensitised. Therefore, we conclude that this steroid hormone and synthetic glucocorticoid are not beneficial to pancreatic beta-cells in vitro.