Mescaline, from peyote and San Pedro cacti, acts on serotonin receptors to produce an altered state consuming a full day and the night after. Controlled studies in healthy people show a large dose-related lift in mood and well-being, reliable nausea and vomiting, and a sustained rise in blood pressure. Lasting benefit remains plausible but unproven. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Seated blood pressure | <120/75 mmHg | Raised for the full 8–14 hour duration |
| Resting heart rate | 50–65 beats/min | Baseline for the dose-dependent rise |
| Corrected QT interval (QTc) on 12-lead electrocardiogram | <430 ms (men), <440 ms (women) | Repolarisation abnormality most likely to become an arrhythmia |
| Estimated glomerular filtration rate (eGFR) | >90 mL/min/1.73 m² | Roughly half the dose is excreted unchanged renally |
| Alanine aminotransferase (ALT) | 10–26 U/L (men), 8–22 U/L (women) | Baseline liver status before partial first-pass metabolism |
| Serum potassium and red-cell magnesium | Potassium 4.0–4.5 mmol/L; red-cell magnesium 5.0–6.5 mg/dL | Low levels lengthen the QT interval; vomiting depletes both |
| Complete blood count | Haemoglobin 14.0–15.0 g/dL (men), 13.5–14.5 g/dL (women); white cells 3.5–6.0 ×10⁹/L | Reference point; no haematological effect observed |
| Fasting glucose and insulin | Glucose 75–85 mg/dL; insulin <5 µIU/mL | Cardiometabolic baseline for the population-level associations |
| High-sensitivity C-reactive protein (hs-CRP) | <0.5 mg/L | Only practical readout for the speculative anti-inflammatory claim |
| Echocardiogram, valve morphology | No leaflet thickening; regurgitation no greater than trace | Repeated 5-HT2B receptor activation is the mechanism behind drug-induced valve fibrosis |
Cadence: Vitals every 30–60 minutes across the 8–14 hour acute window; symptom check at 24 hours; structured review at 1 week and 4 weeks; full panel and blood pressure at 6–12 months where exposure is repeated, with echocardiography only above a few sessions per year.