Plasmapheresis (from the
Greek πλάσμα—plasma, something molded, and
ἀφαίρεσις—aphairesis, taking away) is the removal, treatment, and return of (components of)
blood plasma from
blood circulation. It is thus an
extracorporeal therapy (a medical procedure performed outside the body). The method is also used during plasma donation: blood is removed from the body, blood cells and plasma are separated, the blood cells are returned while the plasma is collected and frozen to preserve it for eventual use in the manufacture of a variety of medications.