Treating a Sore Throat: Rapid Strep Tests

One of the more common reasons patients go to the doctor is “sore throat”. Most sore throats are caused by viral infections that will eventually improve on their own. But some are caused by bacterial infections that are more complicated and take longer to resolve. “Strep Throat” is the most common bacterial infection and is caused by the streptococcal bacteria. Unlike viral infections, bacterial infections can be successfully treated with antibiotics. Thus one of the key questions a physician would want to evaluate is whether a sore throat is viral or bacterial in origin.

The symptoms are very similar and it can be difficult to determine based only on your history and physical examination. The gold standard test is a “throat culture”, which consists of a swab of mucus from your throat incubated for several days to see whether certain bacteria are present. Because this test takes at least 2 days to perform, waiting for the results to come back before initiating treatment will cause the patient to endure more symptoms in the interim if it was positive. On the other hand, most sore throats are not bacterial and the doctor will run a high risk of prescribing unnecessary antibiotics if he prescribed without waiting for a positive test result.

Thus, most physician offices use “Rapid Strep Tests” in their office. As with throat cultures, the Rapid Strep test uses a swab of mucus collected during your office visit. However the test looks for antibodies related to the bacteria, rather than directly measuring the bacteria. The test is not as accurate as the throat culture, so many physicians will decide whether to initiate treatment based off of the Rapid Strep test but simultaneously order a throat culture in addition. If the throat culture results differ from the Rapid Strep results, then the physician can alter treatment via a simple phone call rather than an additional office visit. Both tests are relatively inexpensive and this can be a cost-effective way of diagnosing and treating sore throats.

Some CRMA offices offer a new “Immunoassay” version of the Rapid Strep test that is almost as reliable as a throat culture, but can be done within an office visit similar to the old Rapid Strep test. The immunoassay test requires a special piece of lab equipment and is considerably more expensive to perform. The advantage is it’s so reliable that you will not need a throat culture in addition. If you have an insurance plan with a deductible, the cost of this test will likely track to your deductible and you will pay out of pocket. Since this test is more expensive (typically $70) than traditional Rapid Strep tests, you should inform your provider if this cost will be a concern for you.

If your sore throat is caused by a viral infection, it will typically resolve on its own within five to seven days and does not require any formal medical treatment. You can use simple over-the-counter medications to treat the symptoms. If your sore throat is caused by a bacteria infection and you are prescribed antibiotics, be sure take the full course of medication prescribed. Even if you feel better, you should continue to take the medication as prescribed.