Diffusion and fate of intramuscularly injected human rabies immune globulin

The importance of rabies immune globulin (RIG) in postexposure rabies treatment is well known and it has been emphasized that the local injection into the animal bite sites is crucial. This preliminary study used a radioisotope tracer that allows following the fate of human rabies immune globulin (HRIG) injected intramuscularly. There was significant retention and local diffusion of the immune globulin at the injection site and significant radiotracer could still be detected at the site 24 h later.