Abstract

Diptheria Antitoxin has again become available from the Lister Institute. It contains 4000 international units/ml of refined anti-diptheria globulin prepared from horse serum and is intended for the prevention of diphtheria in susceptible persons exposed to risk of infection, and for therapeutic use. A dose of 500 – 2000 units by intramuscular injection is sufficient to protect a diphtheria contact for about two weeks. When used for this purpose it should always be combined with active immunisation, the antitoxin being given in one arm and the first dose of adsorbed toxoid in the other. For therapeutic use antitoxin is given as soon as possible after diagnosis as an intravenous or intramuscular injection of 10,000 – 100,000 I. U. according to the clinical picture. The use of diphtheria antitoxin may result in serum sickness or anaphylactic shock particularly in allergic patients and in those who have previously received an injection of horse serum. Therefore it is advisable to defer treatment until 30 minutes after a test dose, instructions for which are provided by the Lister Institute. When the administration of antitoxin is undesirable, contacts in a closed community can be given penicillin or erythromycin instead of antitoxin.