Imatinib induces hypothyroidism in patients receiving levothyroxine.

摘要: Interactions of imatinib with other drugs have been scarcely reported. We report a previously unknown effect on levothyroxine therapy. Eleven patients (1 gastrointestinal stromal tumor and 10 medullary thyroid carcinoma) received imatinib. Eight had undergone thyroidectomy used levothyroxine, 3 the in situ. Thyroid function was measured before, during, within 2 weeks after any change either or dosage. observed symptoms hypothyroidism all who thyroidectomy, whereas situ remained clinically biochemically euthyroid. On average, thyrotropin (INN, thyrotrophin) levels increased to 384% +/- 228% upper limit free thyroxine (fT4) tri-iodothyronine (fT3) values reference range (59% 17% for fT4 63% 4% fT3). Clinicians should be aware that hypothyroid subjects receiving high likelihood replacement closely monitored elevations indicating worsening hypothyroidism.