It has no antibacterial activity in vitro. After oral administration, it is hydrolyzed into chloramphenicol by pancreatic lipase to exert antibacterial effects. It has antibacterial activity against aerobic Gram-negative and Gram-positive bacteria, anaerobic bacteria, Rickettsia, spirochetes and Chlamydia. It has bactericidal effects on influenza bacilli, Streptococcus pneumoniae and Neisseria meningitidis, and only has antibacterial effects on Staphylococcus aureus. It exerts its effects by inhibiting bacterial protein synthesis.

This product is the palmitate of chloramphenicol. It has no antibacterial activity in vitro. After oral administration, it is hydrolyzed into chloramphenicol by pancreatic lipase in the duodenum and absorbed into the body to exert its antibacterial effect. It has antibacterial activity against aerobic Gram-negative bacteria and Gram-positive bacteria, anaerobic bacteria, Rickettsia, spirochetes and Chlamydia. It has bactericidal effects on influenza bacilli, Streptococcus pneumoniae and Neisseria meningitidis; it only has antibacterial effects on anaerobic bacteria such as Staphylococcus aureus, Streptococcus pyogenes, Streptococcus viridans, Group B lytic Streptococci, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Salmonella typhi, Salmonella paratyphi, Shigella, Bacteroides fragilis, etc. Pseudomonas aeruginosa, Acinetobacter, Enterobacter, Serratia marcescens, indole-positive Proteus, methicillin-resistant Staphylococcus and Enterococcus are usually resistant to chloramphenicol. Chloramphenicol is fat-soluble and enters bacterial cells by diffusion, and reversibly binds to the 50S subunit of bacterial ribosomes, inhibiting the formation of peptide chains and thus preventing protein synthesis.