Prior studies have reported variously on the presence or absence of dissociative effects at subanesthtetic doses of ketamine administered for treatment-resistant depression. This mixedmethods study emulated the protocol used for the studies in question, with IV administration of 0.5mg/kg over 40 minutes with eight experienced ketamine users. Quantitative measures were generally insignificant since this was not a population reporting depression; blood pressure increased as expected by 20-30mm systolic and 6-20mm diastolic, falling rapidly by 20 minutes after completion of the infusion. Individual qualitative reports reports of relaxation, pleasant sensation, decreased cognitive function, and some disabling of ordinary capacities. As experienced users, subjects commented freely on what was characterized as the triviality of the experience, and typically expressed skepticism that ketamine could have antidepressant properties when administered at this dose or in this manner, as well as disbelief that it could be beneficial except perhaps as a period of relaxation, or as a partial break from ordinary states of mind in naïve subjects. Group discussion produced a consensus recommendation in favor of threshold- and higher-dosage transformative work beginning with a 40-50mg IM bolus, potentially in a series of sessions with higher dosages if indicated, with the number of sessions to be determined by clinical practice; such work should occur in a closely monitored psychotherapeutic setting.
Wolfson, P. E. (2014). Ketamine for Depression: A Mixed-Methods Study. International Journal of Transpersonal Studies, 33(2).
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