Strep throat requires antibiotics. Unlike a regular sore throat caused by a virus, strep is a bacterial infection that won’t resolve on its own and can lead to serious complications if left untreated. The standard treatment course is 10 days of oral antibiotics, and most people start feeling significantly better within 48 hours of the first dose.
How Strep Throat Is Diagnosed
Not every sore throat is strep. Doctors use a simple scoring system to gauge the likelihood before testing. Four features raise suspicion: fever above 100.4°F, swollen or pus-covered tonsils, tender lymph nodes at the front of your neck, and the absence of a cough. If you have all four, the probability of strep is still only about 57%. With two or three, it drops to 21 to 38%. With zero or one, you’re looking at roughly 7 to 12%.
Because symptoms alone aren’t reliable enough, a rapid strep test or throat culture is needed to confirm the diagnosis. The rapid test takes minutes. If it comes back negative but your doctor still suspects strep, a throat culture (which takes one to two days) can catch cases the rapid test misses. Antibiotics should only be started once strep is confirmed, since treating a viral sore throat with antibiotics does nothing and contributes to resistance.
The Standard Antibiotic Treatment
Penicillin and amoxicillin are the first-choice antibiotics for strep throat, recommended by both the CDC and the Infectious Diseases Society of America. Neither has developed resistance to group A strep bacteria, which makes them reliably effective decades after they were first used. Adults typically take penicillin V (500 mg twice daily) or amoxicillin for 10 days. Children receive weight-based doses of amoxicillin, often as a once-daily liquid.
The full 10-day course matters even though you’ll feel better long before it’s finished. Stopping early leaves bacteria alive and increases the risk of the infection returning or triggering complications. If swallowing pills for 10 days sounds difficult, especially for a child, a single injection of penicillin at the doctor’s office is an alternative that eliminates the compliance problem entirely.
If you’re allergic to penicillin, your doctor will choose an alternative antibiotic, typically from a different drug class. The specific option depends on the severity of your allergy. A mild rash from penicillin as a child points toward different alternatives than a history of anaphylaxis.
Managing Pain and Fever at Home
Antibiotics kill the bacteria, but they don’t provide immediate pain relief. Over-the-counter pain relievers fill that gap. Both ibuprofen and acetaminophen effectively reduce throat pain and fever within the first 24 hours. Research published in BMJ Evidence-Based Medicine found no evidence that ibuprofen works better than acetaminophen for sore throat pain, so either one is a reasonable choice. You can alternate them if one alone isn’t enough.
Salt water gargles and throat lozenges can temporarily soothe the back of your throat, but they won’t shorten the illness or fight the infection. Think of them as comfort measures, not treatments. Staying hydrated matters more than most people realize. Warm broths, cold popsicles, and room-temperature water are all easier to swallow than acidic or scratchy foods. Soft foods like yogurt, mashed potatoes, and smoothies help you keep eating when swallowing hurts.
When You Stop Being Contagious
You become non-contagious within 12 hours of your first antibiotic dose. That’s the standard used by schools and daycares for readmission: 12 hours on antibiotics plus no fever. Without antibiotics, strep remains contagious for two to three weeks, even as symptoms fluctuate.
During the contagious window, strep spreads through respiratory droplets. Sharing cups, utensils, or close face-to-face contact are the main routes. Replacing your toothbrush after starting antibiotics is a simple precaution, and keeping shared surfaces like bathroom counters clean reduces the chance of spreading it to family members.
What Happens If Strep Goes Untreated
The biggest reason strep throat demands antibiotics is the risk of rheumatic fever, a condition where the immune system attacks the heart, joints, and nervous system. Rheumatic fever can permanently damage heart valves. It’s rare in the U.S. today precisely because strep is routinely treated with antibiotics, but it remains common in parts of the world where antibiotic access is limited.
A second complication is post-streptococcal glomerulonephritis, an inflammatory kidney condition that can develop about 10 days after strep symptoms begin. It’s not a kidney infection. Rather, the immune system’s response to strep accidentally damages the kidneys’ filtering units. Most people, especially children, recover within a few weeks. Long-term kidney damage is rare but more likely in adults than in children.
In children specifically, repeated strep infections have been linked to a condition called PANDAS, where the immune response to strep triggers sudden-onset OCD, tics, or both. The diagnostic criteria include symptoms beginning between age 3 and puberty, a confirmed strep infection within three months of symptom onset, and an episodic pattern where symptoms flare and fade. PANDAS remains an area of active clinical discussion, but awareness is important for parents who notice abrupt behavioral changes in a child with recent strep.
Recurring Strep Infections
Some people, particularly children, get strep throat repeatedly. A single episode per year is common and not a cause for concern beyond treating each one. But when infections stack up, tonsillectomy becomes a consideration. The clinical threshold is 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. Each episode should be documented with a positive test, not just a sore throat.
Tonsillectomy doesn’t guarantee strep will never return, since the bacteria infect throat tissue beyond the tonsils. But it significantly reduces the frequency and severity of episodes in children who meet the criteria. For adults with recurrent strep, the decision is more nuanced because adults recover from tonsillectomy more slowly and with more pain than children do. The benefits need to clearly outweigh a harder recovery.