A plant-derived compound whose single dose produces a day-long altered state and apparently lasting change. Clearest signals: rapid end of opioid withdrawal, craving reduction lasting months, better mood, trauma symptoms and thinking after repeated head impacts — nearly all from small studies without comparison groups. It has caused fatal heart-rhythm disturbances; screening and monitoring appear to reduce, not eliminate, that hazard. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Corrected QT interval (QTc), 12-lead electrocardiogram | <430 ms (men), <440 ms (women) | Window in which fatal arrhythmia occurs |
| Serum potassium | 4.0–4.5 mmol/L | Low potassium lengthens the QT interval |
| Serum and red blood cell magnesium | Serum 0.85–1.05 mmol/L; red cell upper half of range | Stabilises cardiac membranes |
| Ionised calcium | 1.18–1.30 mmol/L | Low ionised calcium prolongs QT |
| Alanine aminotransferase and aspartate aminotransferase | <25 U/L (men), <20 U/L (women) | Governs conversion to the active metabolite |
| Estimated glomerular filtration rate (eGFR) | >90 mL/min/1.73 m² | Governs metabolite elimination |
| CYP2D6 genotype and metaboliser status | Normal (extensive) metaboliser | Determines clearance, peak exposure and cardiac risk |
| Thyroid-stimulating hormone (TSH) | 0.5–2.0 mIU/L | Thyroid state alters conduction and QT |
| Complete blood count (haemoglobin, haematocrit) | 13.5–15.5 g/dL (men), 12.5–14.5 g/dL (women) | Anaemia reduces tolerance of bradycardia |
| Echocardiogram (structural assessment) | Normal chambers; ejection fraction >55% | Detects structural disease that makes arrhythmia lethal |
Cadence: Baseline panel within 30 days; electrolytes and an electrocardiogram (ECG) repeated the morning of dosing. Continuous telemetry at least 48 hours; ECG with electrolytes at 24 and 72 hours and one week; liver and kidney function at four weeks; ECG plus full panel at three months, and at six to twelve months if abnormal or repeat treatment is contemplated.