Polymyxin B is frequently used to treat infections of the urinary tract, blood, eyes, and meninges. In these cases, this antibiotic is administered by injection. Typically, it is a prescription-only antibiotic. However, polymyxin B can be mixed with bacitracin. This creates an over-the-counter antibiotic ointment that is sold under the brand Polysporin. It is intended for use on skin, and it helps treat minor skin wounds, including scrapes, cuts, and burns. The ointment may help the wounds heal more quickly as well. Some individuals also apply this ointment to their skin to treat or prevent mild infections.
Patients should clean the affected area before using Polysporin. Once the area is dry, they must apply a thin layer of the ointment and rub it carefully into their skin. Patients can safely apply this antibiotic ointment up to three times per day. If desired, they can cover the treated area with a bandage after application. However, they need to use a new bandage every time that they apply ointment. If symptoms persist or worsen after using this ointment for seven days, the patient should consult a physician.