Antibiotics for strep throat

Examples

Penicillin is often the first choice of antibiotic for strep throat unless you are allergic to it.

Most antibiotics are taken for 10 days. Or, a single shot of penicillin may be given. The shot does not help you get better any faster than other types of penicillin.

How It Works

Antibiotics help kill the bacteria that cause infection. This may make you feel better 1 or 2 days sooner than if you did not take an antibiotic. But if you have strep throat, taking an antibiotic is important because it reduces your chance of getting rheumatic fever, which can damage your heart valves.¹ Taking an antibiotic also lowers your chance of getting a serious infection near your tonsils (peritonsillar abscess).

Why It Is Used

Antibiotics may be prescribed if you have strep throat. Your doctor may diagnose strep throat by talking to you, examining you, and looking in your mouth. The doctor also may lightly rub the back of your throat with a long cotton swab, to test for strep bacteria.

How Well It Works

Antibiotics usually make you feel better within 1 to 2 days. They lower the chance you will get either a serious infection near your tonsils (peritonsillar abscess) or rheumatic fever, which can damage your heart. They also lower the chance that you will spread the infection to other people. Most people who take antibiotics for their strep throat are not contagious 24 to 48 hours after starting the medicine.

Side Effects

Side effects of antibiotics may include:

• A skin rash.
• Diarrhea.
• Nausea.
• In rare cases, a life-threatening reaction (anaphylaxis) along with hives, shortness of breath, and shock.

Antibiotics also can change the normal bacteria in your body. This can lead to problems such as:

• A vaginal yeast infection.
• An infection of the intestines caused by Clostridium difficile bacteria (pseudomembranous enterocolitis).

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

It is possible for a person to carry strep bacteria in the throat but not have any symptoms. Antibiotic treatment is not usually needed if the strep infection is not actively causing symptoms. But it may be beneficial for the person carrying strep to be treated with antibiotics if he or she has a history of rheumatic fever, frequent strep throat infections, or family members with recurring strep infections.

It is important to take all of the antibiotic your doctor prescribes. Do not stop taking the antibiotic early just because you feel better. The infection may not go away if you do not take all of the antibiotic, as prescribed by your health professional.

Although it is important to take antibiotics for strep throat, they will not help if your sore throat is caused by a virus instead of strep bacteria. If you take antibiotics when you don't need them, they may not work when you do need them. Each time you take antibiotics, you are more likely to have some bacteria that the medicine does not kill. Over time, these bacteria can change (mutate) and become harder to kill. The antibiotics that used to kill them will no longer work. These bacteria are called antibiotic-resistant bacteria.

If you have trouble taking the medicines as prescribed due to side effects or other concerns, contact your doctor.

Children who have strep throat should stay home from day care or school until they have taken at least 1 full day of antibiotics and they are feeling well enough to return.

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