It is often possible to treat a sinus infection and congestion at home, without the use of antibiotics. Drinking plenty of clear fluids, irrigating the nose and sinuses with a warm saline solution, and inhaling steam can all help to cure a sinus infection and congestion. Saline nasal sprays can also provide some relief from congestion, and steroid nasal sprays can offer temporary relief.
A sinus infection and congestion can sometimes be prevented by regularly blowing the nose and irrigating the sinuses, and by drinking plenty of water. If you have a cold, for example, constantly sniffling can cause a sinus infection, so keep blowing the nose. Taking antihistamines can prevent sinus infections that are caused by allergies and irritants in the air, and they can also help to relieve the pain from an existing sinus infection.
A neti pot can be a great way to treat a sinus infection and congestion. This is a small pot that looks a bit like a gravy boat with a narrow spout; it is filled with a warm saline solution and inserted into one nostril. The water then runs out into one nostril and out the other, clearing congestion and removing irritants from the nasal passages. It is important to only use a neti pot if your nose is not completely clogged; if it is impossible to breathe through the nose at all, the salt water could get trapped in the sinus cavity and cause a bit of pain. It won't cause damage, but it can be unpleasant.
Inhaling warm steam can also help to treat a sinus infection and congestion. Stand over a pot of hot water or take a hot shower to get steam. Some people also put a few drops of menthol or peppermint in the water for extra help clearing congestion. Nasal sprays can be helpful, but it is preferable to use a plain saline nasal spray than a steroid nasal spray, because it is easy to become dependent on the steroid nasal sprays. Over the counter decongestants can provide some relief as well.
Of course, sometimes the only way to treat a sinus infection is with antibiotics or antifungal medication. Persistent sinus infections should always be treated by a doctor, and can become very serious if ignored. In this case, it is especially important to take all the prescribed antibiotics, even if you feel better. Not taking all the prescribed medication can cause you to develop another sinus infection that is resistant to antibiotics, which can make things much more difficult.