Review Question - QID 215173

A 38-year-old man presents to his primary care physician for an annual physical exam. He reports no changes to his health over the last year and generally feels well. His past medical history is significant for childhood asthma, but he does not currently require any medications. He takes a multivitamin daily and drinks 1-2 beers per night. He has never smoked and is not sexually active. His lab results were significant for elevated serum glucose over the last few years, so a hemoglobin A1c test is obtained showing 7.9% modification. He is prescribed metformin and presents to the emergency department several hours after his first dose with bilateral deep venous thromboses. Which of the following best describes this patient's drug reaction?