The use of ketamine as a treatment for mood disorders continues to grow in popularity. However, the differences between individuals consuming ketamine within clinical settings and those self-medicating in casual, non-clinical settings has not been yet characterized. Using the 2023 Global Psychedelic Survey, this study aimed to examine the demographic and clinical characteristics, as well as the self-reported effectiveness and hallucination-related side effects, of ketamine use by comparing individuals using ketamine with and without medical supervision. Compared to clinical ketamine consumers (n = 238), non-clinical consumers (n = 222) were more experienced in use of various psychedelic (p < .0001) and non-psychedelic recreational substances (p < .001), and lifetime use of ketamine (p < .0001). Both groups presented with similar mild depression and anxiety symptoms at the time of the survey collection (p = .22, p = .46). Ketamine was similarly and highly rated in effectiveness within both groups when rated on a scale of 0-100 (83.3 +/- 15.0 clinical, 81.2 +/- 16.6 non-clinical; p = .45). Non-clinical consumers presented higher odds of reporting long-term hallucinations following ketamine use (OR = 2.58, 95% CI: 1.08-6.31). The results of this study indicate a high self-reported effectiveness of ketamine in clinical and non-clinical settings while emphasizing the potential risks of side effects when used without medical supervision.
