What Are the Uses of Neomycin and Polymyxin B?

Both of the antibiotics neomycin and polymyxin B can attack and kill a variety of bacterial species. As antibiotics, the drugs can cure infections in many parts of the body, but common uses for the combination include treatment of skin, eye, and urinary infections. Often, the two drugs are present in a single medication product along with a steroid drug, or another type of antibiotic, for the best result.

Neomycin and polymyxin B are both produced by bacterial species in a raw material form. naturally makes neomycin, and Bacillus polymyxa makes polymixin. In nature, these substances can be useful to the growth of the parent species as they kill some other competing bacteria in the environment, leaving more space and nutrients for the antibiotic producers.

Many different species of bacteria can cause infections, in many areas of the body. Common examples of infectious bacteria include Staphylococcus aureus, Escherichia coli and Haemophilus influenzae. The combination of neomycin and polymyxin B can target these species of bacteria and some others, which makes the drugs useful in treating a variety of infections.

Typically, though, neomycin and polymyxin B are used to treat four major regions of infection, and are not used in injection or pill form. Outer treatable regions of the body are the skin, the eyes and the ears, but the membranes of the urinary tract can also benefit from this combination antibiotic. To treat the urinary tract infection, it is necessary to rinse out the tract with the antibiotic solution using a catheter, instead of administering the drugs through pills or injections.

Products which simply include neomycin and polymyxin B are primarily aimed at treating infections caused by susceptible bacteria in the urinary tract and on the skin. Generally, eye preparations and ear preparations, along with some products for use on the skin, include another ingredient. Most commonly, the extra ingredient is a steroid drug, which helps to reduce inflammation and swelling caused by the immune response, while the antibiotics kill the bacteria causing the infection.

Ingestion of the drugs, or injections straight into the body, can cause toxic effects on people, which is why these particular antibiotics are prepared in topical or solution form. Even in these forms, absorption into the body can occur through broken skin or burns, and if the medicine gets into the body, it can damage the kidneys and the nervous system. Unborn children may also be affected if a pregnant woman absorbs the neomycin portion of the medication.