The subject invention demonstrates a novel antibacterial activity for 2-phenyl-1,2-benzisoselenazol-3(2H)-one 1-oxide, commonly referred to as ebselen se-oxide, and is directed to the treatment of bacterial infections by administration of an effective amount of said compound. Bacterial infections include those infections which are either systemic or superficial in nature. The treatment is intended for a variety of animals, such as premature neonates to adult humans. Administration of ebselen se-oxide to treat superficial bacterial infections may be performed by a topical application, such as via an ointment, a spray, a cream, a mouth wash, an eye drop solution, an ear drop solution, a soap, a gel, or a lotion. In addition, an antibacterial capsule can be administered orally or intravaginally. Administration of ebselen se-oxide to treat systemic bacterial infections may be performed by an intravenous route, a rectal route, an intranasal route, an oral route, an intramuscular route, or by inhalation. Administration of said compound may also be achieved via aerosol, which can be generated by a nebulizer. Ebselen se-oxide may be administered alone, or with a carrier such as dimethylsulfoxide (DMSO), an alcohol, or other suitable carrier. The effective daily amount of ebselen se-oxide is from about 1 μg/kg to 10 mg/kg of body weight.
