Anaphylaxis.

The clinical syndrome of anaphylaxis may be produced by a number of mechanisms. The life-threatening clinical features are angioneurotic oedema, bronchospasm, cardiovascular collapse and pulmonary oedema. The initial treatment consists of general resuscitation plus adrenaline. In shock, colloid solutions should be used to restore blood volume. The pulmonary oedema that occurs is a membrane oedema, and should be treated with artificial ventilation, positive end expiratory pressure, and volume replacement. After a reaction, all available tests should be used to determine the cause, and the patient should be given a warning letter describing the evidence for attributing his reaction to the determined cause. (This should be done in addition to the provision of any identification bracelet.) Pharmacological pretreatment is a valid preventive manoeuvre, but is not 100% reliable.