INS and Hashimoto thyroiditis: <h4>Purpose</h4>To report a case of polydrug ingestion involving levothyroxine and insulin in an adolescent, demonstrating potential protective effects of insulin co-ingestion against symptomatic thyrotoxicosis.<h4>Methods</h4>A 14-year-old female with type 1 diabetes and Hashimoto thyroiditis presented following intentional ingestion of 6.75 milligrams levothyroxine, 60 units insulin aspart, and 80 units insulin degludec.