Kirkegaard C, Smith E
Psychol Med. 1978 Aug;8(3):501-3. doi: 10.1017/s0033291700016202.
Thyrotropin response to thyrotropin-releasing hormone is impaired during endogenous depression and normalized between the depressive periods. Changes in the thyrotropin response to thyrotropin-releasing hormone were shown to be of predictive value and might be useful in the control of continuation therapy with antidepressants in patients with endogenous depression.