The changes of thyroid hormone during pharmacological treatment of panic disorder patients

1. Because imipramine has lowered T4 in uncontrolled studies we examined the effect of imipramine on serum thyroid levels in panic disorder patients in a double-blind placebo and diazepam treatment controlled study. 2. Treatment with imipramine (10 subjects) was associated with a significant decrease of T4 and FTI and treatment with diazepam (8 subject) was associated with a significant decrease of T4. However, there was no significant difference across treatment groups. 3. This finding suggests that previously reported decreases in thyroid hormones during antidepressant therapy may be due to nonspecific effects of treatment rather than to the drug itself.