Toxicological studies on combined preparation of Chloramphenicol and Acetylspiramycin named 661-CA

Combined preparation of chloramphenicol (CP) and acetylspiramycin (ASPM), named 661-CA, was compared with each of the two agents in the toxicological studies. The observations are summarized as follows. 1. Acute toxicity LD_50 of CP, ASPM and 661-CA given by parenteral and oral routes to mice, rats and rabbits are shown in Table-1. 661-CA was intermediate in toxicity between CP and ASPM. 2. Subacute and chronic toxicity These three agents were administered orally to Donryu strain rats for six months. Death appeared within 27-48days in 2g/kg dose groups and the mortality is 60% in ASPM, 20% in CP and 661-CA, respectively. The cause of death may correspond with action of CP