Management of Type 2 Amiodarone-Induced Thyrotoxicosis With a Combination of Low-Dose Prednisone and Bile Acid Resin to Attain Euthyroid State

Background/Objective: In general, with type 2 amiodarone-induced thyrotoxicosis (type 2 AIT), initial treatment with glucocorticoids (oral prednisone, 30 to 40 mg/d) is recommended. However, for patients with type 2 AIT who have active hepatitis B (HBV) or osteoporosis, high-dose prednisone is relatively contraindicated. We report 2 cases of type 2 AIT that were managed with a combination of moderately low-dose prednisone and bile acid binding resin. Case Report: The first patient, a 68-year-old man with atrial fibrillation and active chronic HBV, developed thyrotoxicosis after 6 months of amiodarone therapy. The second patient, a 59-year-old woman with osteoporosis, developed hyperthyroidism after 6 months of amiodarone use. In both cases, thyroid function studies suggested type 2 AIT. Color doppler ultrasonography and nuclear studies also supported a diagnosis of type 2 AIT. The patients were treated with a combination of moderately low-dose prednisone (25 mg/d and 20 mg/d, respectively) and bile acid binding resins (colestipol 3 g/d and cholestyramine 12 g/d, respectively). Over 3 months, thyroid hormone levels normalized without complications. Discussion: Glucocorticoid use in HBV can increase viral reactivation risk, while in osteoporosis it accelerates bone loss. Bile acid resins disrupt the enterohepatic circulation of both thyroid hormones and amiodarone, promoting their rapid elimination. This combination treatment effectively managed thyrotoxicosis while minimizing steroid exposure. Conclusion: In patients with type 2 AIT and relative contraindication to high-dose steroids, a combination of moderately low-dose prednisone and bile acid binding resins offers a safe and effective treatment alternative.