There are many reasons for recurring sinus infections. To treat and prevent them, you need to figure out why they happen in the first place.

Here are some possibilities:

• Sometimes, the makeup of your nose is the problem. If you have a deviated nasal septum or a narrowed sinus ostium (drainage site for the sinus), it can block drainage and lead to infection. Fixing these can solve the problem.
• If you have allergies, it can cause swelling in your nose and get in the way of drainage. Allergy treatment will help.
• Your immune system might not be functioning normally. This could put you at risk for frequent infections. HIV/AIDS, diabetes, autoimmune diseases, cancer and chemotherapy are associated with weak immune systems. Treatment is primarily aimed at controlling these conditions.
• If you have polyps or tumors in your nose, they can block drainage. Treatment depends upon diagnosing the obstruction and pursuing proper therapy.
• Sometimes being around inhalants (like cigarette smoke and dust) can cause the inner part of your nose to swell. This could lead to a sinus infection.
• There are also rare causes for sinus infections, such as immotile cilia syndrome and cystic fibrosis. These require special testing to diagnose.

Whatever the cause, I recommend an appointment with an ear, nose and throat specialist (an otolaryngologist). He or she will perform a thorough history and physical exam. Then you can get tested to get to the right diagnosis and therapy.