What Is a Throat Culture? When Do I Need One?

A throat culture is a lab test your doctor uses to find and identify germs in the back of your mouth that are making you sick.

Why It's Done

Your doctor will probably order this test if you or your child complain of a sore throat and he thinks something other than a virus is to blame.

Some of the infections that can be identified on a throat culture are:

How It’s Done

You’ll be asked to tilt your head back slightly, open your mouth, and say “Ahhhh.” Your doctor will quickly and gently move a cotton swab around the tonsil area in the back of your mouth. He’ll place it in a germ-free container and send it to a lab for testing.

There, doctors place the sample in a special container with other chemicals to make bacteria and fungi grow. The type of germs that grow, if any, shows your doctor what kind of infection you have. Then he’ll decide what medicine will work best for you.

How It Feels

The test can be a little uncomfortable but only lasts a few seconds. You might feel like you have to gag when the doctor swabs your throat -- that’s normal. But you’ll have to stay still and keep your mouth open so he can get a good sample. If not, he might miss some germs, and you might not get the right medicine.

How Soon Will I Get Results?

Results take about 2 to 5 days, because it takes a while for germs to grow in a lab.

But if your doctor thinks you might have strep, he’ll do a quick strep test during your visit. It will show results right away. If it shows you have strep, he’ll give you an antibiotic that fights a wide range of germs.

If the strep test is negative but your throat culture comes back positive for strep or another infection, your doctor’s office will contact you and change your medication if they need to.

What Else Should I Know?

If you or your child has a sore throat and needs to go to the doctor, skip the mouthwash before your visit. It could affect the results of your throat culture.

WebMD Medical Reference Reviewed by Minesh Khatri, MD on September 18, 2018

Sources

SOURCES:

Brookside Press. Nursing Fundamentals, 2007.  

KidsHealth: “Strep Test: Throat Culture.”

Children’s Hospitals & Clinics of Minnesota: “Throat Culture.”

Golisano Children’s Hospital: “Throat Culture.”

Fischbach F. Manual of Laboratory and Diagnostic Tests, Lippincott Williams & Wilkins, 2009.

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