Chloramphenicol is the generic name for a powerful, broad-spectrum antibiotic available in oral and topical formats. Commercially known as Chloromycetin or CHPC, it can be effective for certain infections, such as eye or central nervous system infections. However, chloramphenicol's dosing requirements and potential interactions with other drugs make its use impractical in some situations.
Chloramphenicol has a host of benefits: It's able to infiltrate infected tissues other antibiotics can't access quite so easily. As well, given its cell-penetrating properties, it's effective on intracellular parasites, such as rickettsia, chlamydia and mycoplasma. The medication kills highly vulnerable bacteria; what it doesn't destroy, it leaves for the dog's immune system to take care of on its own.
Uses for Chloramphenicol
Chloramphenicol's versatility means it has a variety of uses in dogs. In ointment form, it's effective for treating eye infections, such as conjunctivitis. The drug is also available in 100 mg, 250 mg and 500 mg tablets and capsules, as well as a liquid suspension. This form is useful for treating internal infections. Veterinary Partner notes in addition to being an effective medication for some parasites and the central nervous system, chloramphenicol works well on infections involving the prostate. Other uses include treating tick-transmitted diseases, pneumonia, skin, bone and wound infections and intestinal infections.
Side Effects of Chloramphenicol
Though chloramphenicol is extremely effective, it's not the most convenient medication to administer. Typically, it's administered three times a day, which can be difficult for many pet owners, particularly if they have a work schedule to maintain. Side effects are minimal but include nausea, diarrhea and decreased appetite. In very young animals, chloramphenicol can accumulate to toxic levels, so it's typically not recommended for pregnant or lactating dogs. Some dogs may experience blood dyscrasias, the production of abnormal blood cells or no production of normal blood cells. If your dog shows side effects to chloramphenicol, contact your vet to discuss an alternative antibiotic.
Contraindications of Chloramphenicol
Chloramphenicol interacts with other drugs, including seizure medications such as phenobarbital and phenytoin, making them last longer than anticipated. Phenobarbital and some antibiotics, such as amoxicillin, erythromycin and tylosin, can interfere with chloramphenicol's effectiveness. It should not be used in dogs with nonregenerative anemia or abnormal bone marrow, nor should dogs with kidney or liver disease take it. Newly vaccinated dogs should avoid chloramphenicol.
Wash your hands after handling chloramphenicol, as people can develop fatal aplastic anemia if ingesting this antibiotic. Though the risk is low -- 1 in 25,000 -- the condition is irreversible.