Article: Neosporin

Neosporin (from Neo, (Greek) new + Sporos, (Greek) seed) is the product name of a antibiotic ointment produced by Pfizer used in the prevention of infection and speeding the healing of wounds. The original ointment contains three different antibiotics: bacitracin, neomycin, and polymyxin B. Other brand names for this mixture include Mycitracin® and Topisporin®.

Neomycin and polymyxin are effective in killing gram-negative bacteria, while bacitracin targets gram-positive bacteria; hence, this 'triple antibiotic' ointment covers for a wide range of bacteria which may infect wounds.

However, these antibiotics are generally only used topically, because they are known for causing serious side effects (such as nephrotoxicity) when used parenterally. Even when used topically, the antibiotic ointment may cause side effects; in particular, neomycin is well-known for causing allergic reactions such as allergic contact dermatitis.

Pfizer also produces a related mixture of bacitracin and polymyxin, branded Polysporin®. Because neomycin is not included in Polysporin®, Polysporin® may be safely used in individuals with allergies to neomycin. Polysporin® Eye/Ear Drops, available over the counter in Canada, do not contain bacitracin, but rather, Gramicidin. It is suitable for ailments such as pink eye or swimmer's ear.