Strep throat is treated with antibiotics, most commonly penicillin or amoxicillin, taken for a full 10-day course. Most people start feeling better within a day or two of starting treatment, but completing all 10 days is essential to fully clear the infection and prevent serious complications.
First-Line Antibiotics
Penicillin and amoxicillin are the go-to treatments for strep throat, and group A strep bacteria have never developed resistance to either one. That’s unusual in an era of growing antibiotic resistance, and it’s the main reason these two drugs have remained the standard for decades.
Amoxicillin is often preferred for children because it tastes better in liquid form and can be taken just once or twice a day. Adults typically take penicillin twice daily. Both are prescribed for 10 days regardless of age. Your provider will choose the dose based on body weight for children or a standard adult dose.
If You’re Allergic to Penicillin
Several alternatives exist for people with a penicillin allergy. The most common substitutes are cephalosporin-type antibiotics like cephalexin, which work through a similar mechanism but are generally safe for people with mild penicillin allergies. These are also taken for 10 days.
For more severe penicillin allergies, providers may prescribe clindamycin or clarithromycin instead. One important caveat: roughly 1 in 3 invasive group A strep infections now involve bacteria resistant to erythromycin and clindamycin, according to CDC surveillance data. That resistance rate is worth knowing if you’ve been prescribed one of these alternatives and aren’t improving after a few days.
Why the Full 10 Days Matter
This is the part most people struggle with. You’ll likely feel dramatically better within 48 hours, and the temptation to stop taking your antibiotic is real. But the 10-day course isn’t about symptom relief. It’s about completely eliminating the bacteria from your throat to prevent a rare but serious complication called rheumatic fever, which can damage the heart valves.
An estimated 1% to 3% of people with untreated strep infections develop rheumatic fever. Of those, up to 60% end up with chronic rheumatic heart disease. These numbers are small on an individual level, but the consequences are severe enough that the 10-day course remains the firm clinical standard. There is no shorter “quick course” option for strep throat the way there is for some other infections.
How Strep Is Diagnosed
Before you get a prescription, your provider needs to confirm strep is actually causing your sore throat. Most offices use a rapid antigen detection test, the familiar throat swab that returns results in minutes. These rapid tests are about 86% sensitive and 95% specific, meaning they’re very reliable when they come back positive but can occasionally miss a true infection.
When a rapid test comes back negative but strep is still strongly suspected (especially in children), a throat culture may be sent to a lab. Cultures take 24 to 48 hours but catch nearly all infections the rapid test misses. This backup step matters most for kids, since they face higher risks from untreated strep than adults do.
When You Can Go Back to Work or School
The general guideline is that you’re no longer contagious after about 12 to 24 hours on antibiotics, provided you no longer have a fever. Most schools and workplaces follow this standard. Without antibiotics, strep remains contagious for two to three weeks even after symptoms improve.
Starting antibiotics also shortens how long you feel sick. Untreated strep throat typically resolves on its own within a week, but antibiotics cut the worst of the symptoms by a day or two and, more importantly, prevent the infection from spreading and triggering complications.
Managing Symptoms at Home
Antibiotics kill the bacteria, but they don’t do much for the pain in the first day or two. Over-the-counter pain relievers like ibuprofen or acetaminophen help with both throat pain and fever. For children, ibuprofen or acetaminophen dosed by weight is appropriate (never aspirin for kids with infections).
Salt water gargles are a time-tested home remedy for sore throat discomfort. Dissolving about half a teaspoon of salt in a glass of warm water and gargling several times a day can soothe inflammation. Cold foods like popsicles or ice chips also help numb throat pain, and staying well hydrated makes swallowing easier as you recover. Warm liquids like broth or tea with honey (for anyone over age one) are another option that many people find soothing.
Recurrent Strep Infections
Some people, especially children, get strep throat repeatedly. A single recurrence is common and doesn’t usually change the treatment approach. You’ll get another round of antibiotics, potentially a different one if your provider suspects the first didn’t fully clear the bacteria.
When infections become truly frequent, tonsil removal may be considered. The clinical threshold is specific: seven or more episodes in one year, five or more per year for two consecutive years, or three or more per year for three consecutive years. Meeting this bar doesn’t make surgery automatic, but it does make it a reasonable option to discuss. Tonsillectomy reduces the frequency of throat infections in the first year or two after surgery, though it doesn’t guarantee you’ll never get strep again since the bacteria infect throat tissue, not just the tonsils.
What Happens if Strep Goes Untreated
Most untreated strep throat resolves on its own within about a week. The danger isn’t the sore throat itself but the immune response it can trigger. Rheumatic fever, which typically appears two to four weeks after the infection, occurs when the immune system attacks the body’s own tissues, particularly heart valves and joints. This is the primary reason antibiotics are prescribed for strep and not for ordinary viral sore throats.
Another possible complication is post-streptococcal kidney inflammation, which can cause dark or bloody urine, swelling, and high blood pressure one to three weeks after infection. A peritonsillar abscess, a pocket of pus forming near the tonsil, is a more immediate complication that causes severe one-sided throat pain and difficulty opening the mouth. These complications are uncommon with prompt antibiotic treatment, which is the core reason strep throat is one of the few sore throats that genuinely requires antibiotics.