What Is Polymyxin B Sulfate?

Polymyxin B sulfate is an antibiotic medication that works to eliminate bacterial infections. It is often used for localized infections, such as eye infections, and it may be combined with other drugs, such as trimethoprim or oxytetracycline. Specifically, polymyxin B sulfate is a polypeptide antibiotic that is considered to be too toxic to be ingested orally, but instead it is generally safe when used topically on the skin or eyes. Before using this drug, patients should discuss its proper use and the potential side effects with the prescribing physician.

Patients should always wash their hands thoroughly before and after applying this antibiotic. When it is applied to an eye, the patient should tilt his head back and gently pull down the lower eyelid. The prescribed amount of the medicine should be placed into the space between the lower eyelid and the eyeball. He should then close his eyes and apply gentle pressure to the corner of the eyelid that is closest to his nose. After about two minutes, the patient may wipe off any excess ointment.

Certain precautions should be followed while using polymyxin B sulfate. Patients must avoid wearing contact lenses during treatment, and they should use a fresh pair of contact lenses after the infection is cleared up. The applicator tip of the medicine should never touch any surface, including the eyelid. In addition, patients must be careful to administer the full course of antibiotics, because discontinuing the drug too soon may cause the bacterial infection to return.

Some side effects may occur with the use of polymyxin B sulfate, which should be reported to the prescribing physician if they become severe. Patients may experience mild stinging or irritation with each application, along with itching or redness. Temporary blurred vision and sensitivity to light may occur.

More serious side effects occur rarely, but should be reported to the doctor as soon as possible. Some people have noticed swelling or crusting of the eyelid, along with persistent redness and irritation. Eye pain and excessive tearing of the eye should also be reported to the doctor. Rarely, an allergic reaction may occur, which typically presents with swelling of the facial region, tightness in the chest, and difficulty breathing, along with hives and a rash.

Before using polymyxin B sulfate, patients should disclose their other medical conditions, medications, and supplements. Women who are pregnant or breastfeeding should discuss the potential risks with their doctors. Polymyxin B sulfate may be contraindicated for use by those with certain allergies or a blood disease called porphyria.