There's a good chance you don't even need to use medicine, says Dr. Sean O'Leary, a professor of pediatrics at the University of Colorado School of Medicine and Children's Hospital Colorado, as well as the chair of the Committee on Infectious Diseases for the American Academy of Pediatrics (AAP). "These medicines are not curative. They don't alter the duration of the illness or anything like that. They are essentially purely for comfort," he tells NPR.