Acute bronchitis is an infection of the major bronchial tubes that lead to the lungs. It usually follows the cold or flu virus, when your immune system is weakened and your lungs are already irritated. To treat bronchitis, you may need to use over-the-counter pain medication or medication meant to soothe your throat, while also getting plenty of rest, drinking warm fluids, easing chest discomfort with a hot compress, and breathing in steam to soothe your bronchial passageways. If your symptoms get severe or persist beyond a week, call the doctor to determine the appropriate treatment.