Cortisol level response to 1- and 2-mg doses of dexamethasone.

Sixteen depressed patients underwent 1- and 2-mg overnight dexamethasone suppression tests in balanced order. Serum cortisol concentrations at all time points were significantly higher after the 1-mg dose. Nine patients were nonsuppressors after the 1-mg dose, and 4 after the 2-mg dose.