What Is Thiamphenicol?

Thiamphenicol is an antibiotic that is most often used in veterinary medicine. Only certain countries allow the use of the drug on humans, while others permit it only for animal use. The antibiotic targets a variety of bacterial species, and cows, pigs and chickens are the primary markets for the antibiotic usage. It kills certain bacteria or retards their growth, which can be useful in cases of disease where no other drug is suitable.

Where thiamphenicol is approved for use in humans, the drug can be used to help clear respiratory infections. Streptococcus pneumoniae and Haemophilus influenzae are two bacterial species that are responsible for many infections of the respiratory tract. These two species are susceptible to the killing action of thiamphenicol, but as other antibiotics with a better safety profile can also cure the majority of these infections, thiamphenicol tends only to be used in poorer countries with a lack of access to better medicines.

The killing action of the antibiotic is due to its effects on the maintenance and growth systems of the susceptible bacteria. Microbes need to produce proteins to remain healthy and to replicate themselves, and the drug blocks the normal healthy production of these proteins. As well as respiratory pathogens, thiamphenicol can also act on a variety of other infectious organisms, such as some of those associated with fecal transmission of infections and some bacteria that typically live on the skin and cause a variety of diseases. Although some of the susceptible bacteria can be killed with low concentrations of thiamphenicol, some are only prevented from growing and multiplying by the drug, in a situation known as "bacteriostatic."

In general, thiamphenicol is a wide-spectrum antibiotic, which means it can be beneficial in treating a wide variety of infections. Commonly, animals receiving the drug get an injection or may have the antibiotic placed into their feed. Although this type of animal use is approved in countries like Italy and France, human use is approved in countries such as Indonesia and Taiwan.

A potential use of the drug in the future is to treat infections that have become resistant to commonly used antibiotics. Resistance to an antibiotic is a common occurrence with regard to bacteria, as bacterial cells in general can gain mutations quite easily, which may make the pathogen resistant to a certain treatment. Bacteria tend to be more resistant to commonly used antibiotics and less resistant to drugs that are not commonly used, which makes thiamphenicol a potential future treatment for infections that have developed resistance to many other antibiotics.