High dose intravenous ascorbic acid masking hypoglycemia in a patient presenting with stroke-like symptoms: A case report

Point of care glucometers are commonly used in the emergency setting on patients presenting with stroke-like symptoms to rule out abnormal glucose levels as a cause. High doses of intravenous (IV) ascorbic acid have been shown to interfere with the accuracy of point of care glucose readings and some continuous glucose monitors (CGM). This interaction can cause falsely elevated point of care glucose readings which can mask true hypoglycemia. A 65-year-old female with a past medical history of leukemia and type 1 diabetes mellitus on an insulin pump presented with stroke-like symptoms after receiving an IV infusion of high dose ascorbic acid as an adjunctive cancer treatment. Point of care glucose upon emergency department arrival was 127 mg/dL, however, serum glucose resulted as 36 mg/dL. The serum glucose was thought to be an error when a repeated point of care glucose was 128 mg/dL. The patient was considered for thrombolytic therapy, but it was ultimately held. A repeat serum glucose was again critically low at 37 mg/dL, and around this time the drug-device interaction was discovered. The patient was given IV dextrose with immediate resolution of her symptoms. Symptoms of hypoglycemia can mimic stroke, and not recognizing hypoglycemia could result in inappropriate thrombolytic administration or delayed correction of glucose. As outpatient vitamin and hydration clinics are becoming more prevalent, providers should be aware of the drug-device interaction between IV ascorbic acid and glucose meters that could negatively impact care.