SGLT2 Inhibitors and False Positive Toxicology Tests

This correspondence reports a case of a patient on empagliflozin (an SGLT2 inhibitor) who experienced false positive urine toxicology tests for ethanol due to microbial fermentation of urinary glucose. The patient, a man in his 60s with diabetes, had abstained from alcohol for over 10 months but tested positive for ethanol in multiple probation office urine samples. Subsequent testing at a primary care facility revealed no ethanol initially, but a repeat test after 24 hours at room temperature turned positive, likely due to bacterial fermentation of glucose excreted via SGLT2 inhibition. The letter highlights the risks of improper urine sample handling and storage, emphasizing the need for awareness among clinicians, patients, and legal authorities to prevent misinterpretation of such results.

This correspondence reports a case of a patient on empagliflozin (an SGLT2 inhibitor) who experienced false positive urine toxicology tests for ethanol due to microbial fermentation of urinary glucose. The patient, a man in his 60s with diabetes, had abstained from alcohol for over 10 months but tested positive for ethanol in multiple probation office urine samples. Subsequent testing at a primary care facility revealed no ethanol initially, but a repeat test after 24 hours at room temperature turned positive, likely due to bacterial fermentation of glucose excreted via SGLT2 inhibition. The letter highlights the risks of improper urine sample handling and storage, emphasizing the need for awareness among clinicians, patients, and legal authorities to prevent misinterpretation of such results.