Sinusitis—inflammation in the nasal and sinus cavities that causes pressure and pain—is a common affliction, and a common treatment has been a course of antibiotics. Yet, in 90 to 98 percent of all sinusitis cases, antibiotics are ineffective.

That's because almost all sinus infections are viral, for which antibiotics are useless. Currently, an overwhelming one in five antibiotic prescriptions for adults are written for sinusitis, also known as acute rhinosinusitis. Many patients insist on a prescription because they mistakenly believe antibiotics cure the infection.

The Infectious Diseases Society of America (IDSA) has released new guidelines that drive home the message that doctors should discourage antibiotic use to treat viral sinusitis. Not only do unnecessary antibiotics expose patients to side effects and higher costs, but overprescribing the drug also contributes to the growing public health concern of antibiotic resistance.

Findings published in the Journal of the American Medical Association help confirm antibiotics' ineffectiveness against sinusitis. Researchers followed 166 patients with sinusitis to assess symptom relief for those prescribed either amoxicillin or a placebo.

They found no significant difference between symptom severity in either group at day three and day 10 of treatment. The IDSA guidelines suggest how to distinguish between viral and bacterial sinus infections. Unfortunately, no simple test exists that can do this, so the guidelines state that doctors should suspect a bacterial infection when symptoms last 10 days or more and don't improve. After that time, they should prescribe a five- to seven-day course of antibiotics—specifically, amoxicillin combined with the beta-lactamase inhibitor clavulanate, which prevents bacteria from destroying amoxicillin.

Common sinusitis symptoms include:

  • Stuffy or blocked nose
  • Mucous discharge from the nose
  • Pain or pressure in the face or teeth

Sinusitis can be brought on by a cold, an upper-respiratory infection, allergies or environmental irritants and can sometimes be accompanied by fever, cough and loss of sense of smell.

When to see the doctor

Most sinus infections get better on their own. However, if symptoms don't improve after 10 days, see your doctor. Call your doctor immediately if symptoms are severe, you have a fever of 102˚F or higher, nasal discharge is thick or contains pus, facial pain lasts three or more days or symptoms get worse after they get better following an upper-respiratory infection. These may be signs that the infection is bacterial, so amoxicillin will work for you.

Source: Prepared by the Editors of The Johns Hopkins Medical Letter: Health After 50

Publication Review By: the Editorial Staff at

Published: 19 Jul 2013

Last Modified: 26 Feb 2015