Key Points
- Strep throat is a bacterial infection of the throat and tonsils caused by group A Streptococcus (GAS).
- It commonly causes a sudden sore throat and fever and differs from viral sore throats.
- Testing is required to confirm strep throat.
- Antibiotics reduce contagiousness, help people feel better sooner, and lower the risk of complications.
- Untreated strep throat can lead to serious complications, some of which may appear weeks later.
What Is Strep Throat?
Strep throat (streptococcal pharyngitis) is an infection that affects the throat and tonsils. The bacteria cause inflammation, leading to pain, redness, and swelling. Because viral infections can cause similar symptoms, testing is required to confirm strep throat.
Causes
- Strep throat is caused by group A Streptococcus bacteria, also known as group A Streptococcus (group A strep).
- It is not caused by viruses. This makes strep throat different from most other cases of sore throat, which usually occur due to viruses.
- Other factors such as allergies or irritants may cause sore throat symptoms, but they do not cause strep throat itself.
How Strep Throat Spreads
Strep throat spreads easily from person to person, especially in close-contact settings such as households and schools. Transmission occurs through:
- Respiratory droplets released when an infected person coughs, sneezes, talks, or breathes.
- Direct contact with droplets on hands or surfaces, followed by touching the mouth, nose, or eyes.
- Sharing items such as drinking glasses.
People can spread the infection before symptoms appear.
Tips to Prevent Strep Throat
Fortunately, there are several simple steps you can take to lower your risk of getting (or spreading) strep throat:
- Wash your hands often. Use soap and water, scrubbing for at least 20 seconds—especially before eating or after coughing and sneezing.
- Use hand sanitizer. If you’re caught without soap and water, an alcohol-based hand sanitizer like Purell is a handy backup.
- Cover coughs and sneezes. Reach for a tissue if you can, then toss it straight into the trash. If none is handy, aim for the crook of your elbow rather than your hands.
- Avoid sharing personal items. Steer clear of passing around cups, utensils, or water bottles, particularly if someone in your circle is under the weather.
Good hygiene, especially during cold and flu season or in crowded spaces, goes a long way toward keeping strep throat at bay.
Is Strep Throat Contagious?
Yes. Strep throat is contagious.
- Without antibiotic treatment, a person may remain contagious for weeks.
- After starting antibiotics, most people are no longer contagious within 12–48 hours. If you don’t have a fever, you can usually return to regular activities—such as work or school—24 hours after taking your first dose of an antibiotic. This helps prevent spreading the infection to others.
Symptoms of Strep Throat
Common symptoms include:
- Sudden, severe sore throat
- Pain when swallowing
- Fever
- Red and swollen tonsils, sometimes with white patches or streaks
- Swollen and tender lymph nodes in the neck
The sore throat caused by strep can be especially uncomfortable—often more painful than most viral throat infections. Pain with swallowing is common, and the lymph nodes in your neck may feel particularly tender or even swollen to the touch. In some cases, people notice that their sore throat comes on suddenly and feels quite severe right from the start.
Some may also experience a headache or abdominal pain. If a rash develops, it may feel rough, almost like sandpaper. This is sometimes referred to as a “strep rash” and can be a clue in diagnosing the infection.
Symptoms alone cannot confirm strep throat; testing is necessary.
Who Is at Higher Risk?
Strep throat can affect people of all ages, but it is most common in school-aged children. Each year, healthcare providers see more than 616 million new cases of strep throat worldwide. In the United States, strep throat accounts for about 15% to 35% of new sore throat cases in children, and 5% to 15% in adults. While anyone can get strep throat, children and teens are especially at risk, particularly those who spend time in group settings like schools or daycare centers. Risk is higher for people who:
- Live or work in close-contact environments (schools, daycares, households)
- Have frequent exposure to someone with strep throat
Diagnosis and Testing
Healthcare providers diagnose strep throat using:
- A medical history and physical exam
- A rapid strep test
- A throat culture if the rapid test is negative but suspicion remains
Testing is important because antibiotics treat bacterial infections like strep throat but do not treat viral sore throats. Most sore throats are actually caused by viruses, which means antibiotics aren’t helpful in those cases and won’t speed recovery. Viral infections will typically resolve on their own with time, and treatment mainly focuses on relieving discomfort. However, because strep throat is a bacterial infection, antibiotics are needed to clear it up and prevent complications. Proper testing helps ensure you receive the right treatment for your specific type of sore throat.
What Is a Strep Test?
A strep test is used to find out whether you have a strep throat infection caused by group A Streptococcus bacteria. During the test, a healthcare provider gently swabs the back of your throat with a long cotton swab to collect a sample.
There are two main types of strep tests:
- Rapid strep test: This test can provide results in about 20 minutes. If it detects Streptococcus bacteria, your provider can confirm a strep throat diagnosis right away.
- Throat culture: If the rapid test is negative but you still have symptoms, your provider may send the swab to a lab for a throat culture. This more sensitive test takes one to two days but can detect bacteria that the rapid test might miss.
Both tests are quick and cause only mild discomfort. Testing is important, as it helps healthcare providers decide whether antibiotics are needed for your sore throat.
Treatment
Antibiotics
Strep throat is typically treated with antibiotics prescribed by a healthcare provider. Antibiotics:
- Help people feel better sooner
- Reduce how long the infection is contagious
- Lower the risk of complications
What Antibiotics Are Commonly Prescribed for Strep Throat?
The most commonly prescribed antibiotics for strep throat are penicillin and amoxicillin. These medications are effective at clearing the infection and are typically recommended unless you have an allergy.
If you are allergic to penicillin, your healthcare provider will choose an alternative antibiotic, such as a cephalosporin, azithromycin, or clindamycin. Antibiotics may be given as a single injection or more frequently as pills or liquid taken by mouth. Most courses last about 10 days.
It’s important to take the full course of antibiotics exactly as instructed, even if your symptoms improve before you finish. This helps ensure the bacteria are completely eliminated and reduces the risk of complications and antibiotic resistance.
Can I Take Leftover Antibiotics for Strep Throat?
No, you should not use leftover antibiotics—either your own from a previous illness or someone else’s—to treat strep throat. Taking antibiotics that were not specifically prescribed for your current infection may not fully treat the bacteria causing your illness and can lead to complications, including antibiotic resistance and unwanted side effects.
Always consult your healthcare provider for the right diagnosis and treatment. This ensures you receive the proper medication, dosage, and duration to effectively clear the infection and reduce the risk of complications.
Symptom Relief and Self-Care
In addition to antibiotics, supportive care may include:
- Drinking fluids to stay hydrated
- Rest
- Gargling with warm salt water
- Using over-the-counter pain relievers as directed
You can also try several simple home remedies to ease discomfort while you recover:
- Eat soft foods, such as applesauce, yogurt, or soup, that are gentle on a sore throat
- Drink soothing liquids, like warm tea or broth
- Suck on throat lozenges or ice pops (for adults and older children)
- Use a cool-mist vaporizer or humidifier to keep the air moist
Make sure to get plenty of sleep to support your immune system. Avoid giving aspirin to children or teenagers, as it can cause a rare but serious illness called Reye’s syndrome. Always follow dosing instructions for pain relievers such as acetaminophen (Tylenol®) or ibuprofen (Advil®).
These self-care measures can help relieve symptoms, but they do not replace the need for antibiotic treatment if strep throat has been diagnosed.
Can You Get Rid of Strep Throat Overnight?
There’s no quick overnight fix for strep throat, as it is caused by bacteria that require time to be cleared by antibiotics. While starting antibiotic treatment from your healthcare provider will help you feel better and become less contagious—often within 24 to 48 hours—the infection cannot be cured instantly.
In the meantime, you can take steps to ease your discomfort:
- Drink warm fluids like tea or broth to soothe your throat.
- Use over-the-counter pain relievers (such as acetaminophen or ibuprofen) as directed.
- Rest as much as possible.
- Gargle with warm salt water to help relieve soreness.
- Keep hydrated with water and avoid irritating foods.
Even with the right care, patience is key—full recovery typically takes several days.
Can Strep Throat Go Away on Its Own?
Symptoms may improve over time without treatment. However, medical evaluation and antibiotic treatment are recommended because untreated strep throat can lead to serious complications.
Possible Complications
Without proper treatment, strep throat can lead to complications, including:
- Peritonsillar abscess
- Rheumatic fever
- Post-streptococcal glomerulonephritis (a kidney condition)
Some complications may develop weeks after the initial infection.
When to See a Doctor
You should contact a healthcare provider if:
- You think you may have strep throat
- Symptoms are not improving or are worsening
- You have a sore throat with fever
If you or your child has trouble swallowing fluids and cannot maintain hydration, medical evaluation is recommended.
Questions to Ask Your Healthcare Provider About Strep Throat
When visiting your healthcare provider about a possible strep throat infection, consider asking questions such as:
- How long will it take to get results from my strep test?
- Will I need antibiotics, and if so, which type should I take?
- What are the best ways to manage symptoms at home while I recover?
- How long should I stay home from work, school, or daycare to avoid spreading the infection?
- Are there any concerns about my tonsils or overall throat health that I should be aware of?
Clear communication with your provider ensures you understand your treatment plan, ways to feel better, and steps to prevent spreading the infection to others.
Frequently Asked Questions
How do I know if I have strep throat?
Only a medical test can confirm strep throat. Symptoms alone are not enough.
How long is strep throat contagious?
Without antibiotics, a person may be contagious for weeks. With antibiotics, most people are no longer contagious after 12–48 hours.
Can you get strep throat without tonsils?
Yes. People without tonsils can still get strep throat, although it may occur less often.
What’s the difference between strep throat and tonsillitis?
Strep throat is caused by bacteria. Tonsillitis can be caused by viruses or bacteria and does not always involve strep infection.
When should I go to the ER for strep throat?
There is no high-quality evidence defining a universal emergency-room threshold specifically for strep throat. Seek urgent medical care if symptoms are severe or rapidly worsening.
Should I go to urgent care or see my regular doctor?
Both can evaluate and test for strep throat. There is no high-quality evidence showing one setting is always preferable over the other.
How long does strep throat last?
With antibiotics, people often start to feel better within a day or two, and most symptoms resolve within 7–10 days.
What to Do Next If You Suspect Strep Throat
If you think you may have strep throat, seek medical evaluation for testing. Prompt diagnosis and appropriate treatment can reduce symptoms, limit spread, and lower the risk of complications.
APA References List
Centers for Disease Control and Prevention. (2025, July 31). About strep throat. https://www.cdc.gov/group-a-strep/about/strep-throat.html
Centers for Disease Control and Prevention. (2025, November 18). Clinical guidance for group A streptococcal pharyngitis. https://www.cdc.gov/group-a-strep/hcp/clinical-guidance/strep-throat.html
Cleveland Clinic. (2022, December 20). Strep throat: Symptoms, causes & treatment. https://my.clevelandclinic.org/health/diseases/4602-strep-throat
Giordano, C. (2025, December 10). How long are you contagious with strep throat? GoodRx. https://www.goodrx.com/health-topic/infections/how-long-is-strep-contagious
Mayo Foundation for Medical Education and Research. (n.d.). Strep throat — Diagnosis & treatment. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/strep-throat/diagnosis-treatment/drc-20350344
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