Plasma exchange speeded improvement from GBS. It did not cause harm apart from being followed by a probable slight increase in risk of relapse. Despite this, plasma exchange probably increases the chance of complete muscle strength recovery a er one year. No new trials have been done since the first publication of this review in 2001. However trials have been done comparing plasma exchange with intravenous infusion of human immune globulin (the antibody portion of plasma). These trials are included in another Cochrane review and show the e ects of the two treatments are similar.