A new distinction between the euphoric and the anti-depressant effects of methylamphetamine.

The psychological effects of an injection of methylamphetamine have been measured in 22 drug-free patients with endogenous depressive illness and in 9 patients with other psychiatric illness. A new distinction between the time course of the euphoric and anti-depressant effects is described. The euphoric effects were seen in the first hour after the injection, but the anti-depressant effects were delayed for 1--3 hours and then lasted for as long as 36 hours. These findings are at variance with the noradrenaline depletion hypothesis of depressive illness which (in its simplest form) predicts an immediate alleviation of depression as a result of an immediate rise in the concentration of noradrenaline at central receptor sites.