Examples

Antibiotics can be taken orally or intravenously (IV) or by inhaling them through a nose spray. Also, an extended-release dose of amoxicillin-clavulanate is now available.

How It Works

Antibiotics kill or prevent the growth of bacteria that cause some sinus infections.

Acute sinusitis

When using antibiotics to treat acute sinusitis, it may be helpful to remember that:

• The number of days you take antibiotics depends on your general health, how serious your sinusitis is, and the type of antibiotic you are taking.
• A different antibiotic may be needed if your condition does not begin to improve within 3 to 5 days.
• Other medicines, such as decongestants, inhaled corticosteroids, and medicines that help thin the mucus (mucolytics), may be prescribed as well to improve sinus drainage.

Chronic sinusitis

When using antibiotics to treat chronic (long-term) sinusitis, it may be helpful to remember that:

• The number of days you take antibiotics depends on your general health, how serious your sinusitis is, and the type of antibiotic you are taking.
• The choice of antibiotic often depends on which antibiotics have worked well for you in the past. If an antibiotic normally used to treat your sinusitis was successful in the past, it may be used again. If it did not work very well, a different antibiotic may be tried.
• Inhaled antibiotics are now available, although they are not widely used. These may help cure symptoms of chronic sinusitis in some cases. But more study is needed to find out how well they work. ¹
• Other medicines, such as decongestants, inhaled corticosteroids, and medicines that help thin the mucus (mucolytics), may be prescribed as well to improve sinus drainage.

Why It Is Used

Antibiotics may be needed when symptoms of sinusitis do not respond to home treatment, symptoms are severe, or complications (such as pus forming in sinus cavities) develop.

• Amoxicillin is often the first choice in treating sinusitis because it is usually effective and has few side effects. It should not be used if you are allergic to amoxicillin or have been diagnosed with mononucleosis.
• Trimethoprim-sulfamethoxazole may be prescribed for people who are allergic to amoxicillin.

Other antibiotics may be prescribed to treat bacterial infections that are resistant to amoxicillin and trimethoprim-sulfamethoxazole.

How Well It Works

Antibiotic treatment of sinusitis is generally safe and very effective. Most people recover completely when they are treated with antibiotics. A 10-day course of the appropriate antibiotic at the proper dosage cures sinusitis caused by bacterial infection about 90% of the time. ²

If a particular antibiotic is not effective at eliminating the bacteria, or if you do not take it long enough, the infection is likely to return.

Taking the antibiotic at a lower dose for 4 to 6 weeks after the infection clears up may keep the infection from returning. Not all doctors agree that prolonged treatment helps, and there is concern that it can lead to the development of bacteria that are resistant to antibiotics.

Side Effects

The risk of side effects may be greater with certain antibiotics.

Common but mild side effects include:

• A bad taste in the mouth.
• Upset stomach.
• Mild to severe diarrhea.
• Vaginal yeast infection.

Diarrhea and vaginal yeast infections may occur when antibiotics destroy some of the normal and necessary bacteria that live in the body. Eating yogurt may help prevent some of these side effects.

Rare and sometimes serious side effects of antibiotics include:

• Allergic reactions.
• Prolonged diarrhea. Contact your health professional if you develop diarrhea while taking an antibiotic. For more information on this side effect, see diarrhea caused by antibiotics.
• Inflammation or infection of the small or large intestine (enterocolitis).

Levofloxacin and moxifloxacin increase the risk of a tendon rupture or other tendon damage. If you have sudden pain or swelling around your ankle, shoulder, elbow, or hand while taking one of these medicines, tell your doctor. Do not exercise until your doctor says it is okay.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

It is important to take all of the medicine your doctor prescribes. Keep taking it even after you begin to feel better. This is especially important when treating sinusitis because the antibiotics do not easily penetrate the mucus inside the sinuses.

If you are having trouble taking the medicines as prescribed (because of side effects or other reasons), contact your health professional.

Your health professional will try to select an antibiotic that is most likely to kill the bacteria causing your sinusitis. If the antibiotic fails to cure your sinusitis, another may be tried. If your condition does not improve, further testing may be needed to find which antibiotic will work best for you.

Complete the new medication information form (PDF) (What is a PDF document?) to help you understand this medication.