For viral infections treatments are generally only to provide comfort and to prevent dehydration and reactions to high fevers. It seems like a waste of money. You should also go to the doctor immediately if you have chest pain or difficulty breathing. Infection with the flu virus often leads to other infections. Ear, sinus, and bronchial infections are examples of such infections.
Pneumonia can also occur as a result of the flu.
It can be caused by the influenza virus itself or by bacteria invading the virus-damaged lung tissues. With a virus, it's rare that you will bring up any colored mucus. If you are coughing up mucus, it will be clear, light yellow or watery if it is viral. With a bacterial infection, the mucus could be dark yellow or green and could be a symptom of a sinus infection or a bronchitis-type infection. The best time to get one is in the fall, but it's never too late to get one.