There are many, many strains of the flu out there, and there are sometimes secondary complications, like sinus infections and bronchitis or pneumonia that you can get along with the flu that can lengthen your recovery time. Also, every time you are sick, it weakens your immune system, so you need to stay really hydrated, take vitamin C and drink things like Gatorade, vitamin waters or things that will boost your immune system, not water or cokes. Chicken soup actually does help a little, and spicy food can open up those clogged sinuses. Also, use a hydrator in your home if you use central heat, as the air can get really dry and that aggravates irritated throats and lungs. Be sure and take the whole amount of any medicines your doctor prescribes for you, or be sure to take as they directed you to. Other than that, just get a lot of rest and ride it out. There is Tamaflu, and another medication that are prescription that can really shorten the length of your flu, and help minimize the symptoms. Antibiotics will cure any secondary infections.