Depression reduction is the experience of a lasting minimization of symptoms associated with depression and low mood states. It is distinct from effects such as cognitive euphoria, as it does not simply elevate the user's mood while they are currently under the influence of the drug but instead results in a self‐sustaining sense of greater emotional well-being that can last from days to weeks after the substance has been taken. Depression reduction most commonly occurs at varying levels of efficacy under the influence of a range of different substances, primarily psychedelics or dissociatives. However, it can also occur under the influence of meditation and certain entactogens. It is worth noting that this is unlikely to be an isolated effect component but rather the result of a combination of an appropriate setting in conjunction with other coinciding effects such as rejuvenation, introspection, personal bias suppression, and spirituality enhancement. In many cases, it may also stem from the direct neurological changes that occur as a result of the substances’ pharmacological action. There are a number of studies which confirm the presence of this effect within specific substances, a small amount of these are described and listed below:
STUDIESIt has been demonstrated that ketamine, even if taken in small doses, is effective for patients suffering from chronic depression and bipolar disorder. Studies have shown that the effect of the drug is rapid, with the effect onset ranging from immediately to within two hours. It is consistent in relieving a patient’s depressive and/or suicidal symptoms, lasting up to three days after a single dose. A 2015 preliminary report has found a significant reduction of up to 82% in depressive scores following ayahuasca administration. The report concludes that "these results suggest that ayahuasca has fast-acting anxiolytic and antidepressant effects in patients with a depressive disorder." Its acute and fast-acting effects show promise for the treatment of depression as common antidepressants, such as fluoxetine (Prozac), take weeks to show significant effects and are ineffective for many users. While further research is needed to establish the utility of psilocybin and other psychedelics in treating depression, a pilot study has observed significantly decreased depression scores in terminal cancer patients six months after treatment with psilocybin. An open-label study was carried out in 2016 in the UK to investigate the feasibility, safety and efficacy of psilocybin in treating patients with unipolar treatment-resistant depression, with promising results; although the study was small and involved only twelve patients, seven of those patients met formal criteria for remission one week following psilocybin treatment and five of those were still in remission from their depression at three months.