Tolbutamide-Induced Hypoglycemia

Abstract
We review thirteen cases of sulfonylurea-induced hypoglycemia and emphasize that the hypoglycemia may be prolonged, require intensive and repeated therapy and masquerade as cerebral or brain stem infarction. Severe hypoglycemia may occur suddenly after prolonged therapy with one of the sulfonylurea drugs or soon after the initiation of treatment. We report a severe hypoglycemic reaction after a small initial dose of tolbutamide in a patient whose diabetes had previously been excellently controlled with insulin treatment, 25 units per day, but who had lost much weight. We suggest that, in certain circumstances, a change of therapy from insulin to orally administered hypoglycemic agents may not be as safe as has previously been thought. Such a change might be interrupted by careful observation without hypoglycemic therapy.