Steroid-Induced Hyperglycemia

Glucocorticoids such as prednisone, prednisolone, methylprednisolone, and dexamethasone can expose previously unrecognized diabetes or create new hyperglycemia in a person without diabetes. Hyperglycemia occurs in roughly 20% to 50% of people treated with corticosteroids who have no prior diabetes history. The dominant problem is insulin resistance. Skeletal muscle takes up less glucose because insulin signalling no longer moves glucose transporters effectively to the cell surface. The liver continues making and releasing glucose even when insulin should suppress that output. Over time, visceral fat accumulation, lipid deposition, and endoplasmic reticulum stress can impair beta-cell function, reducing the pancreas’s ability to compensate. The result is often a misleading clinical picture: fasting glucose may look acceptable while glucose climbs substantially after meals later in the day. A normal fasting result does not exclude steroid-induced hyperglycemia. Health Canada product information warns that prednisone and prednisolone can reduce glucose tolerance, worsen existing diabetes, or precipitate diabetes in people who are predisposed.