Sore throats lasting longer than a week require medical attention.
What Causes Sore Throat?
Sore throat (also called pharyngitis) is typically caused by a viral or bacterial infection. An estimated 200 to 300 different strains of virus cause colds and sore throat.1 In up to 90% of cases, sore throat is caused by viruses linked to the common cold or flu. The other 10% of cases result from bacterial infections or some other medical condition. The bacteria that most commonly cause sore throat are streptococci. Infection with streptococcal bacteria is commonly called strep throat.

Sore throat can also be caused by irritants such as air that is low in humidity, smoking, air pollution, excessive yelling, postnasal drip caused by allergies, and breathing through the mouth. Injury to the back of the throat and stomach acid backing up into the throat and mouth are other causes of sore throat.2

Although sore throat affects people of all ages, children aged 5 to 15 years, smokers, allergy sufferers, and people with compromised immune systems are at higher risk.3,4

Sore Throat Symptoms
Sore throat symptoms are easily recognized. Your throat hurts and is irritated, swollen, or scratchy. Pain increases when you swallow. You may also have tenderness in your neck. Other symptoms that are commonly associated with sore throat are listed in Table 1.3,5,6

If your sore throat is due to a virus, it should go away within 7 to 10 days. When a person has strep throat, however, throat pain starts out gradually and quickly becomes severe and constant. Swallowing may be difficult. You may also have a fever of 100°F or higher. Symptoms worsen at night.3,4,6 Strep bacteria can lead to other conditions such as infection of the tonsils, sinuses, skin, blood, or middle ear, as well as various inflammatory illnesses. 2 Seek immediate medical help if your symptoms include drooling, an inability to swallow, difficulty opening your mouth, difficulty breathing, redness or swelling of the neck, swollen lymph nodes, bleeding from the throat, or a fever higher than 101°F.7

Treatment
Unless sore throat is caused by a bacterial infection, antibiotics are not prescribed. Antibiotics do not kill viruses—the most common cause of sore throat—and have no impact on symptoms. Using antibiotics unnecessarily creates strains of bacteria that are resistant to antibiotics. Without antibiotics, 85% of patients will be symptom-free within about 1 week.8 Table 24,7,9 lists recommended strategies for managing sore throat pain. If your symptoms do not improve within a week, contact your doctor.

If your doctor believes you have strep throat, he or she may do a rapid antigen strep test, which determines whether you have a strep infection. This test provides results within minutes but is not always accurate. Therefore, your doctor may also take a throat culture, which is considered more accurate, and send it to the lab for testing. Test results are usually available within 24 to 48 hours.6

Antibiotics are effective in treating bacterial infections. Penicillin is the most common antibiotic prescribed for strep throat. If you have a penicillin allergy, your doctor may prescribe erythromycin. Your doctor most likely will give you a 10-day supply. It is critical that you take all of the medication even if your symptoms subside or go away. Soft stool and diarrhea are common side effects of antibiotics. Taking an OTC antidiarrhea agent should minimize these side effects. Along with killing the bacteria that cause strep throat, your doctor will focus on preventing complications from the infection. For example, untreated strep throat can lead to rheumatic fever, which causes heart damage along with kidney problems.10,11

Prevention
People with bacterial infections remain contagious for approximately 24 hours after they begin taking antibiotics. Consequently, if you have strep throat, it’s important to limit your contact with other people until you are no longer contagious. Table 33,6,7,12 lists recommendations for preventing sore throat.

Endnote
Up to 90% of all sore throats are caused by viruses and clear up within a week. Those with a sore throat lasting longer than a week should seek medical intervention.


Dr. Zanni is a psychologist and health-system consultant based in Alexandria, Virginia.