Throat Culture

What is a throat culture?

A throat culture, or throat swab culture, is a test of the germs in the back of your throat. Your healthcare provider uses a throat culture to help diagnose an infection.

During a throat culture, your provider rubs a cotton swab along the back of your throat. They collect a sample of the cells to send to a lab.

At the lab, a technician mixes the sample with chemicals to see whether bacteria or fungi grow. You usually get the test results in two to seven days. If you have an infection, your provider may prescribe medication to help you get better.

When is a throat culture performed?

Healthcare providers may give you a throat culture if you have a sore throat (pharyngitis). The throat culture can show the cause of your illness.

Why would I need a throat culture?

A throat culture is a type of bacteria culture test. Viruses cause many sore throats. But sometimes bacterial infections and fungal infections lead to sore throats. For instance, bacteria group A Streptococcus infection causes strep throat.

Your provider may suspect strep throat if you also have:

• Abdominal pain.
• Fever.
• Headache.
• Loss of appetite.
• Pain and difficulty swallowing.
• Red spots on the roof of your mouth (petechiae).
• Swollen lymph nodes.
• Tonsils that look red with white spots.

If you also have a skin rash and a swollen tongue, your provider may suspect scarlet fever.

You’re more likely to have a viral infection rather than a bacterial or fungal infection if you have a sore throat along with:

• Cough.
• Hoarseness.
• Pink eye (conjunctivitis).
• Runny nose.
• Sneezing.

What does a throat culture diagnose?

Health providers use a throat culture to diagnose conditions, including:

• Diphtheria.
• Gonorrhea.
• Rheumatic fever or scarlet fever.
• Strep throat (bacterial tonsillitis).
• Thrush.
• Whooping cough (pertussis).

What happens before a throat culture?

Before a throat culture, your provider will tell you what to expect during the test. The test isn’t painful, but you may feel a brief tickling or gagging sensation at the back of your throat.

If your child is having a throat culture, your provider may ask you to keep your child still. You may want to sit them on your lap or hold their hand.

Tell your provider if you’ve recently taken antibiotics or used mouthwash. These can affect the test results.

What happens during a throat culture?

During a throat culture, your provider will:

1. Ask you to tilt back your head.
2. Ask you to open your mouth wide and say, “Aaahh.” They may gently push your tongue down with a flat piece of wood (tongue depressor). This can help them to better see the back of your throat.
3. Pass a cotton swab along the back area of your throat and tonsils to take a sample of cells.
4. Place the swab into a sterile, sealed container.

A throat culture usually only takes a few seconds to complete.

Your provider may sometimes use a throat washout to collect a sample of cells. They’ll ask you to gargle saltwater and spit it into a cup. This gives them a larger sample for the throat culture.

What happens after a throat culture?

After a throat culture, your provider sends the sample to a lab. The lab technician puts the sample onto a plate or into a sterile container.

They add chemicals to the sample to see if bacteria or fungi grow. This usually takes about two days for bacteria and up to seven days for a fungus. A negative throat culture means that no bacteria or fungi have grown. A positive throat culture means that the sample did grow bacteria or fungi.

If you have a positive throat culture, the lab technician tests the bacteria or fungi to see what kind of infection you have. Your provider uses this information to make a treatment plan.

Your provider may prescribe medication, such as antibiotics, to treat the infection. They may also suggest nonsteroidal anti-inflammatory drugs (NSAIDs) to help treat throat pain and other symptoms.

When would you have a rapid strep test?

If your provider suspects strep throat, they may do a rapid strep test before or instead of a throat culture. A rapid strep test takes about 20 minutes. A provider wipes the back of your throat with a swab. Then they test the sample for bacteria.

If the test shows a bacterial infection, your provider can start you on antibiotics right away. If the test doesn’t show a bacterial infection, your provider may still do a throat culture to double-check the results.

What are the advantages of a throat culture?

Providers consider throat cultures to be very safe. They’re:

• Helpful in showing whether you have a bacterial or fungal infection.
• Quick.
• Painless.

What are the risks or complications of a throat culture?

There are no known risks or complications of a throat culture.

But people with sudden swelling of their epiglottis (acute epiglottitis) shouldn’t have a throat culture. In that situation, a throat culture can cause even more difficulty breathing.

What is the recovery time after a throat culture?

There’s no recovery time after a throat culture. You can continue with your day-to-day activities immediately.

When can I eat or talk after having a throat culture?

You can eat and talk — and resume all normal activities — right away.

When should I see my healthcare provider?

Talk to your healthcare provider if your symptoms don’t go away or get worse. Also, talk to your provider if you have any of these symptoms during or after your treatment:

• Difficulty swallowing.
• Fever that’s new or higher.
• Fever with a bad headache or neck pain.
• Pain that medication doesn’t help.
• Sore throat that worsens on one side.

A note from Cleveland Clinic

It’s hard to know how much to worry when you have a sore throat. Is it a sign of a more serious condition, or just something that will go away on its own? Getting a throat culture can help you and your provider figure out what’s going on. This painless test only takes a few minutes. A throat culture lets your provider see whether a bacterial or fungal infection has caused your condition. You’ll get test results in two to seven days. If you do have a bacterial or fungal infection, your provider can give you medications to help you feel better.