This post describes a case where a patient had multiple false positive toxicology tests for urinary ethanol after starting therapy with empagliflozin, a sodium–glucose cotransporter 2 (SGLT2) inhibitor.
SGLT2 inhibitors are a class of medications used to treat type 2 diabetes. They work by inhibiting the reabsorption of glucose in the kidneys, leading to excretion of glucose in the urine. Empagliflozin is one such SGLT2 inhibitor.
In this case, the patient, a man in his early 60s, had not consumed alcohol for more than 10 months. However, the last four urine samples he provided to the probation office tested positive for ethanol. The patient was adhering to empagliflozin therapy, which had been prescribed for diabetes mellitus. The urine sample tested positive for ethanol after being stored at room temperature for 24 hours.
This case highlights the potential for false positive urine ethanol tests in patients taking SGLT2 inhibitors. The increased concentration of glucose in the urine provides a fertile ground for bacteria, leading to fermentation and the production of ethanol. This could lead to undue stress and unnecessary investigations for patients subject to urine toxicology testing.
Urine tests for alcohol can accurately detect ethanol and its byproducts 12 to 24 hours after consumption. However, conditions of sample storage can have a significant impact on the test results. Therefore, it is crucial that both patients and healthcare providers are informed about the possible interactions of empagliflozin and other SGLT2 inhibitors.
In summary, the use of SGLT2 inhibitors like empagliflozin can lead to false positive results in urine ethanol tests due to microbial fermentation of glucose in the urine. Proper storage of urine samples and awareness of this potential interaction are important for accurate interpretation of test results.
