Effects of electroconvulsive therapy (ECT) on thyroid function parameters.

Serum concentrations of thyroxine, triiodothyronine, TSH and prolactin were measured in 10 patients with affective disorders receiving ECT. Samples were drawn at -15 min, 0, +30 min, +60 min and +3 hr after ECT. A significant increase in both prolactin and TSH was observed 30 min after ECT. A small but significant decrease in triiodothyronine but no change in thyroxine was found in all post-ECT samples. The increase in TSH may be caused by an anti-dopaminergic effect of ECT at either the pituitary or the hypothalamic level.