Furosemide causes acute and long-term hyperglycaemia and reduces glucose tolerance in mice.

The effect of furosemide on carbohydrate metabolism was studied in mice. Single-dose administration (200 mg kg-1 body weight) resulted in transient hyperglycaemia and a rise in the glucose/insulin ratio within 60 min. The glucose tolerance was impaired with elevated serum glucose and reduced insulin response 2 h after the furosemide injection, but had recovered within 24 h. In mice made hypoglycaemic by prior injection of insulin, the basal serum glucose and the glucose tolerance were impaired 22 h after the injection of furosemide. It is suggested that furosemide has both acute and long-term effects on carbohydrate metabolism in mice and that, at least in part, this is due to reduced insulin secretion. Glucose may protect against the diabetogenic action of furosemide.