Methods for treating acne vulgaris include providing a solution having a peroxide compound, the solution having an antimicrobial effect for reducing bacteria that cause acne vulgaris; topically administering a therapeutically effective amount of the solution to the patient; and once administered, exposing the solution to a wavelength of light that creates a synergistic antimicrobial effect with the solution and enhances the antimicrobial effect of the solution, thereby further reducing or eliminating the bacteria that cause acne vulgaris. The methods may decrease lesions and associated inflammation in patients infected with acne vulgaris.