What is most likely a benefit of using an anti-infective drug rather than an antibiotic drug when treating a urinary tract infection? An anti-infective drug allows the body’s natural defenses to kill bacteria, thus helping the immune system get stronger. Antibiotic drugs kill only bacteria, so another drug would be needed to treat the UTI symptoms and end the infection. Anti-infective drugs can prevent the onset of a UTI because they block sodium and potassium from entering the blood and spreading bacteria. Antibiotic drugs help relieve pain by making parts of the body numb, but they do not remove the infection from the body.