According to a review of 61 studies of patients suffering from severely debilitating depression, a large majority of the patients reported that missing a night' s sleep immediately lifted their depression. Yet sleep-deprivation is not used to treat depression even though the conventional treatments, which use drugs and electric shocks, often have serious side effects.
The fact that sleep-deprivation is not used as a treatment for depression is best explained by the fact that, for a small percentage of depressed patients, missing a night's sleep induces a temporary sense of euphoria.