Medically reviewed on January 3, 2018
Strep throat is a bacterial infection that can make your throat feel sore and scratchy. Strep throat accounts for only a small portion of sore throats.
If untreated, strep throat can cause complications, such as kidney inflammation or rheumatic fever. Rheumatic fever can lead to painful and inflamed joints, a specific type of rash or heart valve damage.
Strep throat is most common in children, but it affects people of all ages. If you or your child has signs or symptoms of strep throat, see your doctor for prompt testing and treatment.
Signs and symptoms of strep throat can include:
- Throat pain that usually comes on quickly
- Painful swallowing
- Red and swollen tonsils, sometimes with white patches or streaks of pus
- Tiny red spots on the area at the back of the roof of the mouth (soft or hard palate)
- Swollen, tender lymph nodes in your neck
- Nausea or vomiting, especially in younger children
- Body aches
It's possible for you or your child to have many of these signs and symptoms but not have strep throat. The cause of these signs and symptoms could be a viral infection or some other illness. That's why your doctor generally tests specifically for strep throat.
It's also possible for you to be exposed to a person who carries strep but shows no symptoms.
When to see a doctor
Call your doctor if you or your child has any of these signs and symptoms:
- A sore throat accompanied by tender, swollen lymph glands
- A sore throat that lasts longer than 48 hours
- A fever higher than 101 F (38.3 C) in older children, or fever lasting longer than 48 hours
- A sore throat accompanied by a rash
- Problems breathing or swallowing
- If strep has been diagnosed, a lack of improvement after taking antibiotics for 48 hours
Strep throat usually causes throat pain and difficulty swallowing. This photo of strep throat shows inflammation and red spots, caused by the infection.
The cause of strep throat is bacteria known as Streptococcus pyogenes, also known as group A streptococcus.
Streptococcal bacteria are highly contagious. They can spread through airborne droplets when someone with the infection coughs or sneezes, or through shared food or drinks. You can also pick up the bacteria from a doorknob or other surface and transfer them to your nose, mouth or eyes.
Several factors can increase your risk of strep throat infection:
- Young age. Strep throat occurs most commonly in children.
- Time of year. Although strep throat can occur anytime, it tends to circulate in late fall and early spring. Strep bacteria flourish wherever groups of people are in close contact.
Although strep throat isn't dangerous, it can lead to serious complications. Antibiotic treatment reduces the risk.
Spread of infection
Strep bacteria may spread, causing infection in:
- Middle ear
Strep infection may lead to inflammatory illnesses, including:
- Scarlet fever, a streptococcal infection characterized by a prominent rash
- Inflammation of the kidney (poststreptococcal glomerulonephritis)
- Rheumatic fever, a serious inflammatory condition that can affect the heart, joints, nervous system and skin
Researchers are investigating a possible link between strep infection and a rare condition called pediatric autoimmune neuropsychiatric disorder associated with group A streptococci (PANDAS). PANDAS is a term used to describe certain children whose symptoms of neuropsychiatric conditions, such as obsessive-compulsive disorder or tic disorders, are worsened by strep infection.
To prevent strep infection:
- Clean your hands. Proper hand cleaning is the best way to prevent all kinds of infections. That's why it's important to clean your own hands regularly and to teach your children how to clean their hands properly using soap and water or an alcohol-based hand sanitizer.
- Cover your mouth. Teach your children to cover their mouths when they cough or sneeze.
- Don't share personal items. Don't share drinking glasses or eating utensils. Wash dishes in hot, soapy water or in a dishwasher.
Your doctor will conduct a physical exam, look for signs and symptoms of strep throat, and probably order one or more of the following tests:
- Rapid antigen test. Your doctor will likely first perform a rapid antigen test on a swab sample from your throat. This test can detect strep bacteria in minutes by looking for substances (antigens) in the throat. If the test is negative but your doctor still suspects strep, he or she might do a throat culture.
- Throat culture. A sterile swab is rubbed over the back of the throat and tonsils to get a sample of the secretions. It's not painful, but it may cause gagging. The sample is then cultured in a laboratory for the presence of bacteria, but results can take as long as two days.
Medications are available to cure strep throat, relieve its symptoms, and prevent its complications and spread.
If you or your child has strep throat, your doctor will likely prescribe an oral antibiotic. If taken within 48 hours of the onset of the illness, antibiotics reduce the duration and severity of symptoms, as well as the risk of complications and the likelihood that infection will spread to others.
With treatment, you or your child should start feeling better in a day or two. Call your doctor if there's no improvement after taking antibiotics for 48 hours.
Children taking an antibiotic who feel well and don't have a fever often can return to school or child care when they're no longer contagious — usually 24 hours after beginning treatment. But be sure to finish all the medicine. Stopping early can lead to recurrences and serious complications, such as rheumatic fever or kidney inflammation.
To relieve throat pain and reduce fever, try over-the-counter pain relievers, such as ibuprofen (Advil, Motrin IB, others) or acetaminophen (Tylenol, others).
Use caution when giving aspirin to children or teenagers. Though aspirin is approved for use in children older than age 3, children and teenagers recovering from chickenpox or flu-like symptoms should never take aspirin. This is because aspirin has been linked to Reye's syndrome, a rare but potentially life-threatening condition, in such children.
Lifestyle and home remedies
In most cases, antibiotics will quickly wipe out the bacteria causing the infection. In the meantime, try these tips to relieve symptoms of strep throat:
- Get plenty of rest. Sleep helps your body fight infection. If you have strep throat, stay home from work if you can. If your child is ill, keep him or her at home until there's no sign of fever, and he or she feels better and has taken an antibiotic for at least 24 hours.
- Drink plenty of water. Keeping a sore throat lubricated and moist eases swallowing and helps prevent dehydration.
- Eat soothing foods. Easy-to-swallow foods include broths, soups, applesauce, cooked cereal, mashed potatoes, soft fruits, yogurt and soft-cooked eggs. You can puree foods in a blender to make them easier to swallow. Cold foods, such as sherbet, frozen yogurt or frozen fruit pops also may be soothing. Avoid spicy foods or acidic foods such as orange juice.
- Gargle with warm salt water. For older children and adults, gargling several times a day can help relieve throat pain. Mix 1/4 teaspoon (1.42 grams) of table salt in 8 ounces (237 milliliters) of warm water. Be sure to tell your child to spit out the liquid after gargling.
- Use a humidifier. Adding moisture to the air can help ease discomfort. Choose a cool-mist humidifier and clean it daily because bacteria and molds can flourish in some humidifiers. Saline nasal sprays also help to keep mucous membranes moist.
- Stay away from irritants. Cigarette smoke can irritate a sore throat and increase the likelihood of infections such as tonsillitis. Avoid fumes from paint or cleaning products, which can irritate throats and lungs.
What you can do
When you make the appointment, ask if there's anything you need to do in advance, such as fasting before having a specific test. Make a list of:
- Symptoms you or your child has, including any that seem unrelated to the reason for your appointment
- Key personal information, including major stresses, recent life changes and family medical history and possible sources of recent infection
- All medications, vitamins or other supplements you or your child takes, including the doses
- Questions to ask your doctor
Take a family member or friend along, if possible, to help you remember the information you're given.
For strep throat, some basic questions to ask your doctor include:
- What's likely causing these signs and symptoms?
- What are other possible causes?
- What tests are needed?
- What treatment approach do you recommend?
- How soon do you expect symptoms to improve with treatment?
- How long will this be contagious? When is it safe to return to school or work?
- What self-care steps might help?
- Is there a generic alternative to the medicine you're prescribing?
Don't hesitate to ask other questions.
What to expect from your doctor
Your doctor is likely to ask a number of questions, including:
- When did the symptoms begin?
- Have the symptoms changed over time?
- How severe are the symptoms?
- Have you or your child been exposed to anyone with strep throat in the last couple of weeks?
- Does anything seem to make the symptoms better or worse?
- Have you or your child been diagnosed with strep throat in the past? When? How was it treated?
- Have you or your child been diagnosed with any other medical conditions?
What you can do in the meantime
If you think you or your child might have a strep infection, take steps to avoid spreading infection:
- Keep your hands clean, cover your mouth when you cough or sneeze and don't share personal items.
- Gargling with 1/4 teaspoon (1.42 grams) of table salt in 8 ounces (237 milliliters) of warm water also may help.
- Resting, drinking fluids, eating soft foods and taking pain relievers, such as ibuprofen (Advil, Motrin IB, others) or acetaminophen (Tylenol, others) may ease symptoms.