Removes the liquid part of the blood and replaces it with a protein solution. A long record in specific diseases; in healthy adults, one small trial. Measured gains were short-lived, appeared on laboratory measures of biological age rather than on how people felt, and concentrated in those starting in poorer health. Harms are common but mostly preventable. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Ionised calcium | 1.15–1.30 mmol/L | Citrate binds calcium; drives the commonest side effect |
| Fibrinogen | 200–350 mg/dL | Falls sharply after albumin-replaced exchange; governs bleeding risk |
| Platelet count | 200–300 × 10⁹/L | Circuit losses compound clotting-factor depletion |
| Prothrombin time / INR | INR 0.9–1.1 | Detects the transient coagulopathy that follows each exchange |
| Serum albumin | 4.2–5.0 g/dL | Confirms replacement is adequate and resynthesis is keeping pace |
| Total immunoglobulin G | 800–1600 mg/dL | Quantifies antibody depletion, the mechanism behind infection risk |
| High-sensitivity C-reactive protein | Below 0.5 mg/L | Tracks the inflammatory burden the procedure is meant to lower |
| Lipoprotein(a) | Below 30 mg/dL (75 nmol/L) | Non-selectively removed; large single-session falls with rebound |
| Estimated glomerular filtration rate | Above 90 mL/min/1.73 m² | Detects volume-shift or contrast-related kidney stress across a course |
| Epigenetic age panel | No established target; track change from the individual's own baseline | The primary outcome in the longevity trials |
Cadence: Full baseline before any course; ionised calcium, fibrinogen and a complete blood count before each session; kidney function every third session; immunoglobulin G at four weeks after a course; clock panel and function tests at one and three months, then every six to twelve months where courses continue.