🔮 Ketamine

2-(2-chlorophenyl)-2-(methylamino)cyclohexanone

Overview

Ketamine is an NMDA receptor antagonist — it works on glutamate, not serotonin, making it mechanistically distinct from classic psychedelics. At sub-anesthetic doses it produces dissociation, dreamlike states, altered body perception, and at higher doses, the "k-hole" — a state of profound dissociative immersion.

Therapeutic Use

Ketamine is the only psychedelic-adjacent substance currently legal and widely prescribed for mental health in the US. IV ketamine clinics treat depression and suicidality. Esketamine (Spravato), a nasal spray form, received FDA approval in 2019 for treatment-resistant depression. The antidepressant mechanism appears to involve rapid synaptogenesis via BDNF and mTOR pathways.

Harm Reduction

• Unlike classic psychedelics, ketamine has real addiction potential.
• Chronic heavy use causes bladder damage (ketamine cystitis) — a serious and sometimes irreversible condition.
• Respiratory depression is possible at very high doses, especially combined with other depressants.
• The dissociative state impairs coordination — falls and accidents are a practical risk.
• In a therapeutic context with appropriate dosing, the safety profile is well-established.