Polygeline is a polymer of urea and polypeptides derived from degraded gelatin. The mean molecular weight of the polygeline molecules is 35000 with a range of 5000 to 50000. It is available as a 3.5 percent solution in 500 ml plastic bottles (Haemaccel) and in addition to the polygeline there is sodium, potassium, calcium and chloride ions. Polygeline is readily excreted in the urine so has a short half life of about 3-6 hours. This half life increases in patients with impaired renal function to about 16 hours. Polygeline is used in the initial management of hypovolaemia where its dose is limited by the degree of haemodilution which can be tolerated by the patient. In adults this amounts to about 1,500 ml. Histamine release has been reported with polygeline and this may result in hypotension, bronchospasm and skin rash. Recent alterations in its preparation have reduced the incidence of reactions to 0.78 percent.