A decades-old anesthetic that, at low doses, eases severe treatment-resistant depression and suicidal thoughts within hours rather than weeks. The strongest support is for rapid mood relief, with weaker support for anxiety and pain. Benefits fade without repeated dosing. Main concerns are detachment during dosing, blood-pressure rises, and—with frequent or unsupervised use—bladder damage and dependence. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Blood pressure | <120/80 mmHg at rest; no acute spike >180/110 during dosing | Ketamine acutely raises blood pressure; uncontrolled hypertension is a contraindication |
| Heart rate | 60–80 bpm at rest | Ketamine increases heart rate via sympathetic stimulation |
| Liver enzymes (ALT, AST) | ALT and AST <25 U/L | Ketamine is cleared by the liver; impaired function prolongs effects |
| Depression rating (e.g., PHQ-9) | <5 (minimal symptoms) | Primary measure of treatment benefit and remission |
| Suicidal ideation score | 0 (none) | Captures ketamine's distinct rapid anti-suicidal effect |
| Urinary symptom screen | No urgency, frequency, or pain | Detects early ketamine-induced bladder toxicity |
Cadence: Vital signs before, during, and after each session; mood, suicidality, and side effects rated at each visit during induction; bladder, cognitive, and dependence screening at baseline, throughout the initial 2–3 week series, then every 1–3 months during maintenance.