Serial use of aprotinin and incidence of allergic reactions.

Allergic reactions to aprotinin, a polypeptide, have been reported on several occasions. A survey of 136 courses of aprotinin, given to patients with gastric cancer as a protease inhibitor, has shown an incidence of less than 1% of acute anaphylaxis and a similar incidence of minor allergic responses. Two cases of acute allergic responses are described. Fifteen patients received repeated courses of aprotinin at 6-weekly intervals and no allergic phenomena were detected. Provided patients are challenged intra-dermally or with eye drops before each course, it is considered that aprotinin is safe to use in repeated fashion.