Chronic alcoholics who had been abstinent from alcohol for more than 2 years were evaluated with the thyrotropin-releasing hormone (TRH) test. The findings suggest the following profound disturbances in the hypothalamic-pituitary-thyroid axis: 1) a "euthyroid sick syndrome," evidenced by low levels of triiodothyronine (T3), high levels of reverse T3, and normal levels of thyroxine (T4) (this syndrome implies a decreased 5'-deiodination of T4 to T3 and of reverse T3 to its lesser iodinated metabolites), 2) an increased binding capacity for thyroid hormones, evidenced by a decreased T3-uptake value and an increased level of T4-binding globulin, and 3) thyroid-stimulating hormone (TSH) blunting in 31% of patients. Paradoxically, there was a positive correlation between basal T4 and delta max TSH in subjects with blunted TSH, but baseline TSH levels were reduced in subjects with and without blunted TSH.