[Uptake and elimination of hepatitis B immunoglobulin after intramuscular administration]

After intramuscular administration of four different hepatitis B immunoglobulins at a dose of 0.1 ml/kg body weight, serum anti-HBs antibody titres were followed over four months in 37 healthy persons. Highest serum concentration averaged 138-355 mU anti-HBs/ml and was generally observed on the third or seventh day after passive immunisation. Immunoglobulins were eliminated with a half-life of 17.5-25 days. Four months after injections their concentration was still 1.2-2.5% of the maximally reached serum level. Intramuscular administration of hepatitis B immunoglobulin does not at once achieve effective optimal viral antibody levels in blood. But since there are no special preparations for intravenous use and active immunization is unlikely to be able to provide immediate protection against hepatitis B virus, intramuscular injection remains further on the method of choice in the prevention of hepatitis B after exposure.