Rickettsiae chloramphenicol against

Chloramphenicol, a broad spectrum antibiotic, is active not only against bacteria but also against other microorganisms, such as rickettsiae. Chloramphenicol has excellent activity against anaerobes. The drug is either bactericidal or (more commonly) bacteriostatic, depending on the organism. 

Chloramphenicol is one of the older broad-spectrum antibiotics. It was introduced in 1948 and grew in popularity because of its high antimicrobial activity against a wide range of Gram-positive and Gram-negative bacteria, Rickettsiae, Chlamydia, and Mycoplasma species. It is particularly useful in infections caused by Salmonella typhi and Haemophilus influenzae. It is mainly bacteriostatic. It readily crosses tissue barriers and diffuses rapidly into nearly all tissues and body fluids. 

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