A Rare Case of Tirzepatide-Associated Immune Thrombocytopenia.

Tirzepatide, a novel dual glucagon inhibitory peptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist, is used in the management of type 2 diabetes mellitus (T2DM) and chronic weight management. There are no current case reports on tirzepatide causing drug-induced thrombocytopenia (DIT) despite its metabolic benefits and common gastrointestinal side effects being well documented. This case report details a 47-year-old male with a history of obesity and T2DM who presented with an ecchymotic, petechial rash within a week of increasing the dose of tirzepatide to 12.5 mg. Pertinent labs showed isolated thrombocytopenia (6000/µL), and other secondary causes of thrombocytopenia were ruled out. The patient was started on intravenous immunoglobulin (IVIG) and steroids. Platelet counts ultimately increased to baseline in response to the treatment with tirzepatide cessation, IVIG, and corticosteroids. Overall, these findings suggest an immune-mediated, drug-induced mechanism of severe thrombocytopenia. Our case intends to raise clinical awareness regarding this potential rare side effect of tirzepatide-induced thrombocytopenia. Prompt discontinuation of the drug and early initiation of steroids/IVIG can prevent life-threatening bleeding and promote recovery.