Chronic pain affects about 1.5 billion people worldwide and is a leading cause of disability. Conventional treatments like opioids and NSAIDs often cause adverse effects and limited long-term relief. This review examines psychedelics—psilocybin, LSD, and ketamine—as alternative therapies. These substances modulate pain through serotonergic and glutamatergic systems and may promote neuroplasticity. The review covers their pharmacologic actions, effects on cancer pain, migraines, and neuropathic pain, and clinical implications, highlighting the need for further research to validate efficacy and optimize use.
High-dose ketamine, used for conditions like Complex Regional Pain Syndrome, is linked to several adverse effects. Psychiatric symptoms such as agitation, anxiety, and sleep disturbances occur across oral, intravenous, and intranasal routes. Emesis is common and more frequent at higher doses. Hepatotoxicity is also common, dose-dependent, and usually transient. Uropathy is another potential adverse effect. When properly monitored in a hospital setting, high-dose ketamine appears safe, though practitioners should note that certain adverse effects are likely dose-dependent.