Lifespan's A - Z Health Information Library

Throat swab culture is a laboratory test done to isolate and identify organisms that may cause infection in the throat.

The back of the throat is swabbed with a sterile cotton swab near the tonsils. The swab is placed in a tube of culture medium. In order to improve the chances of detecting bacteria, the swab may be used to scrape the back of the throat several times. This test is used primarily to identify strep throat. However, depending on the type of culture medium used, other organisms may be detected.

Tilt your head back with your mouth wide open. Resist gagging and closing the mouth while the swab touches the back of the throat near the tonsils. Do not use antiseptic mouthwashes before the test.

Your throat may be sore at the time the test is taken. You may experience a gagging sensation when the back of your throat is touched with the swab, but the test only lasts a few seconds.

The test is performed when a throat infection is suspected, particularly strep throat.

The presence of the usual mouth and throat bacteria is a normal finding.

The growth of certain organisms such as group A beta-hemolytic streptococci (which causes strep throat) as well as other organisms which cause diphtheria and gonorrhea is abnormal and may indicate infection.

This test is safe and well-tolerated. In very few patients, the sensation of gagging may lead to an urge to vomit or cough.