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 antibiotics, but finishing the entire prescription is essential to fully clear the infection and prevent complications.
How Strep Throat Is Diagnosed
Not every sore throat needs antibiotics, so doctors use a simple scoring system to decide whether testing is warranted. You get one point for each of four signs: fever, no cough, white patches or pus on the tonsils, and swollen, tender lymph nodes in the front of the neck. A score of 0 or 1 means strep is unlikely, and testing usually isn’t needed. A score of 2 or higher typically triggers a rapid strep test, which takes about 5 to 10 minutes in the office. At the highest score of 4, some providers will start treatment right away even before results come back.
The rapid test uses a throat swab. If it comes back positive, you’ll get a prescription that day. If it’s negative but your doctor still suspects strep, a throat culture (which takes 24 to 48 hours) can catch cases the rapid test misses.
First-Line Antibiotic Treatment
Penicillin and amoxicillin are the go-to antibiotics for strep throat. Group A Streptococcus, the bacterium that causes strep, remains 100% susceptible to penicillin, meaning resistance is not a concern with this drug. Amoxicillin is often preferred for children because it tastes better in liquid form and can be taken once daily.
Adults typically take penicillin twice a day (500 mg each dose) for 10 days. Children take a lower dose two or three times daily. Amoxicillin can be given once a day in a weight-based dose. For people who are unlikely to finish a 10-day oral course, a single injection of penicillin at the doctor’s office treats the infection in one visit.
The 10-day duration matters even though you’ll feel better much sooner. Stopping early allows surviving bacteria to rebound, which can lead to a relapse or, in rare cases, complications.
If You’re Allergic to Penicillin
People with a penicillin allergy are typically given a different class of antibiotic. However, the alternatives aren’t as reliably effective as they used to be. Surveillance data from England’s 2024-2025 season shows that 18% of Group A Strep samples were resistant to erythromycin, a common backup antibiotic, up from 8% the previous year. Resistance to tetracycline has reached 40%, and clindamycin resistance sits around 9%.
These rising resistance rates make it worth discussing your specific allergy history with your provider. Many people labeled “penicillin allergic” as children can actually tolerate it safely, and allergy testing can clarify this. If you do need an alternative, your provider will choose based on local resistance patterns and your allergy type.
When You Can Go Back to Work or School
The general rule is that you’re no longer contagious after 12 to 24 hours on antibiotics, provided your fever has broken. Most schools and workplaces follow this 24-hour guideline. Without treatment, strep can remain contagious for two to three weeks, even after symptoms fade.
Symptom relief usually begins within one to two days of starting antibiotics. The sore throat tends to improve first, followed by fever and swollen glands. If you don’t notice any improvement after 48 hours, contact your provider, as this could signal a different infection or, rarely, an antibiotic-resistant strain.
Managing Pain and Discomfort 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 acetaminophen (Tylenol), ibuprofen (Advil, Motrin), or naproxen (Aleve) help reduce throat pain and fever. Ibuprofen and naproxen also target inflammation, which can make swallowing more comfortable. Follow the dosing instructions on the label, and avoid giving aspirin to children or teenagers.
Gargling with warm salt water several times a day can reduce swelling and ease soreness. Mix half a teaspoon of salt into one cup of warm water. This won’t replace antibiotics, but it provides real, immediate relief between doses of pain medication. Drinking plenty of fluids keeps the throat moist and prevents dehydration, especially if fever is present. Warm broths, cold popsicles, and soft foods are easiest to get down when swallowing hurts.
Why Treatment Matters
Strep throat will often resolve on its own, but leaving it untreated carries real risks. The most serious is rheumatic fever, an inflammatory condition that can damage the heart valves. The overall rate of rheumatic fever after untreated strep is between 0.3% and 3%, with genetically predisposed individuals (roughly 3% to 6% of the population) accounting for most cases. There’s no way to know in advance if you’re in that group.
Another possible complication is post-streptococcal kidney inflammation, which can develop one to three weeks after infection. Antibiotics reliably prevent rheumatic fever when started within nine days of symptom onset. They also shorten the duration of symptoms by about a day, reduce the contagious window, and prevent the infection from spreading to close contacts.
Recurring strep infections, defined as multiple confirmed episodes within a year, sometimes lead to a conversation about tonsil removal. This is typically reserved for people who get strep frequently despite proper treatment, as the tonsils can harbor bacteria between episodes.