Antibiotics are used to treat infections caused by bacteria. Different types of bacteria can cause a sinus infection, or sinusitis. Some of these bacteria can only be killed off by using the correct antibiotic. A doctor will prescribe the relevant antibiotics, depending on the type of bacterial infection that has caused your sinus infection. There are several antibiotics from which to choose.


Penicillins are a narrow-spectrum antibiotic, which means they will only kill a few forms or types of bacteria. Penicillin keeps bacteria from growing by stopping the bacteria from building its cell walls. Without strong walls, bacteria can't survive. The most common type of penicillin antibiotic prescribed for a sinus infection is Amoxicillin (Amoxil). It is usual for doctors to recommend a 5- to 7-day course of antibiotics for sinus infections.


Fluoroquinolones are a form of broad-spectrum antibiotics. Fluoroquinolones are relatively new, in comparison to other sinus infection antibiotics, and are able to kill the relevant bacteria completely. The two most popular Fluoroquinolone antibiotics are Moxifloxacin and Avelox. These types of antibiotics are strong and can have serious side effects.


Macrolides are antibiotics that block reproduction of the bacteria that is causing the sinus infection, which allows the body's immune systems to destroy the bacteria. Higher doses can destroy the bacteria completely. The two most common Macrolide antibiotics prescribed to patients are Klacid and Biaxin.


Cephalosporins are known as broad-spectrum antibiotics, which means they can cover a range of bacterial infections. Cephalosporins are a type of penicillin, but they have a lower risk of an allergic reaction for individuals who are allergic to penicillin. Cephalosporins have the same fighting effect as penicillin. Three commonly used types of Cephalosporin antibiotics that are used to treat sinus infections are called Cedax, Ceftin and Keflex. Ceftin is stronger than Cedax and Keflex and is normally used to treat difficult sinus infections that have built resistance to other antibiotics.

The Immune System

When an immune system is strong, it can fight off many types of bacteria that cause sinus infections. When the immune system becomes tired and weakened, antibiotics can help to not only remove the bacteria, but can also give the body's immune system a chance to become strong again. By looking after your body and eating a healthy diet, you can prevent certain sinus infections from reoccurring, thanks to your body's stronger immune system.