A sore throat is pain or irritation of the throat. Swallowing often makes it feel worse. The most common cause of a sore throat, also called pharyngitis, is a viral infection, such as a cold or the flu. A sore throat from a virus goes away on its own.

Strep throat, also called a streptococcal infection, is a less common type of sore throat. Bacteria causes it. Strep throat needs treatment with antibiotics.

There are other less common causes of sore throat. They might need more treatment.

Take your child to a healthcare professional if the sore throat doesn't go away after taking a drink in the morning. This advice is from the American Academy of Pediatrics.

Get immediate care for a child who has severe symptoms such as:

• Trouble breathing.
• Not being able to swallow.
• Unusual drooling, which might be from not being able to swallow.

If you're an adult, see a healthcare professional for a sore throat and any of the following problems. This advice comes from the American Academy of Otolaryngology — Head and Neck Surgery:

• A bad sore throat that lasts longer than a week.
• Not being able to swallow.
• Trouble breathing.
• Trouble opening the mouth.
• Joint pain.
• Earache.
• Rash.
• Fever higher than 101 F (38.3 C).
• Bloody mucus.
• Repeated sore throats.
• A lump in the neck.
• Hoarseness that lasts more than two weeks.
• Swelling in the neck or face.

Viruses that cause the common cold and the flu also cause most sore throats. Less often, bacterial infections cause sore throats.

Viral infections

Many viral illnesses cause a sore throat such as:

• Common cold.
• Flu, also called influenza.
• Mono, also called mononucleosis.
• Measles.
• Chickenpox.
• Coronavirus disease 2019 (COVID-19).
• Croup, a common childhood illness that causes a harsh, barking cough.

Bacterial infections

Many bacterial infections can cause a sore throat. The most common bacterium that causes a sore throat is Streptococcus pyogenes, also called group A streptococcus. This bacterium causes strep throat and other illnesses. Strep throat is most common in school-age children and teens.

Other causes

Other causes of a sore throat include:

• Allergies. Allergic reactions can cause a sore throat. The reaction might be to molds, dust, pollen or flecks of skin shed by dogs, cats, and other animals with fur or feathers, also called pet dander. Mucus that builds up and drips down the back of the nose and throat, also called postnasal drip, can make a sore throat worse.
• Dryness. Dry indoor air can make the throat feel rough and scratchy. Breathing through the mouth also can cause a dry, sore throat. An ongoing stuffy nose can cause breathing through the mouth.
• Irritants. Irritants in outdoor and indoor air, also called air pollution, can cause an ongoing sore throat. These include tobacco smoke, chemicals and dust, pollen, and mold. Chewing tobacco, drinking alcohol and eating spicy foods also can irritate the throat.
• Muscle strain. Yelling, talking loudly or talking for a long time without rest can strain muscles in the throat.

• Gastroesophageal reflux disease (GERD). GERD causes stomach acid to back up in the food pipe, also called the esophagus.

  Other symptoms might include heartburn, hoarseness, stomach contents going back up the food pipe and the feeling of having a lump in the throat.

• HIV infection. A sore throat and other flu-like symptoms sometimes appear soon after someone is infected with HIV. Someone who is HIV-positive might have a constant sore throat or one that keeps coming back.
• Tumors. Cancerous tumors of the throat, tongue or voice box, also called the larynx, can cause a sore throat. Other symptoms might include hoarseness, trouble swallowing, noisy breathing, a lump in the neck and bloody mucus.

Rarely, an infected area of tissue, also called an abscess, in the throat can cause a sore throat. So can swelling of the flap that covers the windpipe during swallowing, also called the epiglottis. Either can block the airway, which is a medical emergency.

Anyone can get a sore throat. But some things make it more likely to get one, including:

• Being around tobacco smoke. Smoking and secondhand smoke can irritate the throat. The use of tobacco products also raises the risk of cancers of the mouth, throat and voice box.
• Allergies. People who have seasonal allergies or other allergic reactions are more likely to get a sore throat.
• Being around chemicals. Tiny bits in the air from burning fossil fuels and common household cleaners and other chemicals can cause throat irritation.
• Having sinus infections often. Mucus running down the throat from the nose can irritate the throat or spread infection.
• Being near other people. Viral and bacterial infections spread easily anywhere people get together. This includes child care centers, classrooms, offices, arenas and airplanes.
• Weak immune system. People whose immune system's defenses are low are more likely to get any kind of infection than are other people. Common causes of a weak immune system include HIV, diabetes, treatment with steroids or chemotherapy medicines, stress, fatigue, and poor diet.

The best way to prevent sore throats is to avoid the germs that cause them and to stay clean. Follow these tips and teach children to do the same:

• Wash hands often and well. Wash for at least 20 seconds, especially after using the toilet, before and after eating, and after sneezing or coughing.
• Avoid face touching. Don't touch eyes, nose or mouth.
• Don't share food, drinking glasses or forks, knives and spoons.
• Cough or sneeze into a tissue and throw it away. Then wash hands. If there's no tissue, sneeze into the elbow.
• Use hand cleansers, also called alcohol-based hand sanitizers. Do this to wash hands when there's no soap and water.
• Don't touch public phones or drinking fountains with the mouth.
• Often clean and disinfect phones, doorknobs, light switches, remotes and computer keyboards. On a trip, clean phones, light switches and remotes in the hotel room.
• Stay away from people who are sick or have symptoms.

To diagnose a sore throat, a healthcare professional might:

• Use a tool with a light to look inside the throat, ears and nose.
• Gently feel the neck to check for swollen glands, also called lymph nodes.
• Listen to breathing with a tool called a stethoscope.

Throat swab

A simple test can find streptococcal bacteria, the cause of strep throat. A healthcare professional rubs a sterile swab over the back of the throat to get a sample of mucus. The sample goes to a lab for testing.

Many clinics have a lab that can get a test result for a test called a rapid antigen test within minutes. But a test called a throat culture might give better results. A throat culture goes to a lab that returns results within 24 to 48 hours.

Rapid antigen tests aren't as sensitive as throat cultures, but they're quick. If the antigen test shows no strep, a healthcare professional might send a throat culture to a lab to check again for strep throat.

Usually, a sore throat caused by a virus goes away on its own in 5 to 7 days and doesn’t need treatment. Antibiotics don't treat a virus.

To ease pain and fever, many people use acetaminophen (Tylenol, others) or other mild pain relievers.

For infants and children with sore throats, there are pain medicines you can get without a prescription that are made for them. These include acetaminophen (Children's Tylenol, Infants' FeverAll, others) or ibuprofen (Children's Advil, Children's Motrin, others).

Never give aspirin to children or teenagers because it has been linked to Reye's syndrome, a rare but potentially life-threatening condition that causes swelling in the liver and brain.

Treating bacterial infections

A sore throat caused by a bacterial infection needs antibiotics to treat it.

Anyone taking an antibiotic must take all the medicine even if the symptoms are gone. Not taking all the medicine as directed can cause the infection to get worse or to spread to other parts of the body.

Not taking all the antibiotics to treat strep throat can raise a child's risk of a disease that can harm the heart, called rheumatic fever, or serious kidney inflammation.

Talk to your doctor or pharmacist about what to do if you forget a dose.

Other treatments

For sore throats from other illnesses than viral or bacterial infections, treatment depends on the diagnosis.

Use the following to ease the symptoms of a sore throat:

• Rest. Get plenty of sleep. Rest the voice, too.
• Drink more fluids. Fluids keep the throat moist. Avoid caffeine and alcohol, which can be drying.
• Try foods and drinks that comfort. Drink warm liquids that soothe the throat such as broth, tea without caffeine or warm water with honey. Cold treats such as ice pops also can soothe a sore throat. Don't give honey to children younger than age 1.
• Gargle with saltwater. A saltwater gargle of 1/4 to 1/2 teaspoon (1250-2500 milligrams) of table salt to 4 to 8 ounces (120 to 240 milliliters) of warm water can help soothe a sore throat. Children older than 6 and adults can gargle the water and then spit it out.
• Add moisture to the air. Use a machine called a humidifier to get rid of dry air that can irritate a sore throat. Clean the humidifier often so it doesn't grow mold or bacteria. Sitting for several minutes in a steamy bathroom also might help.
• Suck on hard candy or cough drops, also called lozenges. Either can soothe a sore throat. Don't give them to children age 4 and younger because they might choke on them.
• Avoid irritants. Keep the home free from cigarette smoke and cleaning products that can bother the throat.
• Stay at home until no longer sick. This can help protect others from catching a cold or other virus.

Although many alternative treatments are often used to soothe a sore throat, there's little proof that they work. And they might cause harm.

Check with your healthcare professional before using herbs. They can affect medicines. They might not be safe for children, people who are pregnant or breastfeeding, and people with certain health conditions.

Herbal or alternative products for a sore throat often come as teas, sprays or lozenges. They include:

• Slippery elm.
• Licorice root.
• Marshmallow root.

You're likely to start by seeing your family healthcare professional. You then might be referred to a specialist in ear, nose and throat (ENT) problems. Or you might be referred to an allergy specialist, known as an allergist.

Here's some information to help you get ready for your appointment.

What you can do

Make a list of:

• Symptoms you or your child has, and for how long.
• Key personal information, such as recent contact with someone who was ill.
• All medicines, vitamins or other supplements you or your child takes, including doses.
• Questions to ask your healthcare professional.

For a sore throat, some questions to ask include:

• What's likely causing these symptoms?
• Are there other possible causes?
• What tests are needed?
• What treatment do you recommend?
• How soon do you expect symptoms to improve with treatment?
• How long will this be catching? When is it safe to return to school or work?
• What self-care steps might help?

Ask any other questions you have.

What to expect from your doctor

Your healthcare professional is likely to ask questions, including:

• Are there symptoms other than a sore throat?
• Have these symptoms included a fever? How high?
• Have there been breathing problems?
• Does anything make the sore throat worse, such as swallowing?
• Does anything seem to make the symptoms better?
• Has anyone else at home been ill?
• Do you often have a sore throat?
• Do you smoke? Are you or your child often exposed to secondhand smoke?