Yes! The sulfamethoxazole component of TMP-SMX contains the identical sulfanilamide structural group as sulfonylureas used as oral hypoglycemics1. It appears to act through mimicking the action of sulfonyureas on the pancreatic islet cells by acting as an insulin secretagogue leading to increased insulin secretion1. Increased levels of plasma insulin dropping following interruption of TMP-SMX has been reported, and is thought to be dose and time dependent1,2.
A major risk factor for this complication is impaired renal function, but poor hepatic function, and concurrent use of drugs that decrease plasma glucose levels have also been implicated (1,2). Occasionally there are no obvious risk factors.
- Forde DG, Aberdein J, Tunbidge A, et al. Hypoglycemia associated with co-trimoxazole use in a 56-year-old caucasian woman with renal impairment. BMJ Case Reports 2012;doi:101136/bcr-2012-007215.
- Nunnai G, Celesia BM, Bellissimo F, et al. Trimethoprim-sulfamethoxazole-associated severe hypoglycemia: a sulfonylurea-like effect. Eur Rev Med Pharmacol Sci 2010;14:1015-18.