If your cough lasts more than 1 month or if you keep having a fever, you should see your doctor. You should also see your doctor if you cough up blood. If you have trouble breathing only when you lie down, or if your feet swell, you need to see your doctor. The best defense against acute bronchitis is not to smoke. Smoking damages the bronchial tree and makes it easier for viruses to cause infection.
Smoking also slows down the healing time, so that it takes longer to get well.