The standard medicine for strep throat is an antibiotic, almost always amoxicillin or penicillin. These two drugs have been the go-to treatment for decades because the bacteria that cause strep throat have never developed resistance to them. Your doctor will also likely recommend over-the-counter pain relievers to manage throat pain and fever while the antibiotic does its work.
Amoxicillin and Penicillin: The First Choice
Amoxicillin is the most commonly prescribed option, especially for children, because it tastes better in liquid form and can be taken once or twice a day. The typical course is 10 days. Penicillin works just as well but requires more frequent dosing for adolescents and adults, usually twice or four times daily for 10 days.
Both antibiotics are inexpensive and widely available. Group A strep bacteria are not resistant to either one, which is why they remain the first-line treatment even as resistance to other antibiotics has climbed. Around 1 in 3 invasive group A strep infections now show resistance to other antibiotic classes like erythromycin and clindamycin, but penicillin and amoxicillin remain fully effective.
If You’re Allergic to Penicillin
A penicillin allergy changes the picture. Your doctor will choose from a few alternatives depending on the type of allergic reaction you’ve had.
If your allergy caused a rash but not a severe reaction like throat swelling or difficulty breathing, a first-generation cephalosporin is typically the next option. These are in a related antibiotic family but are generally safe for people whose penicillin allergy isn’t the severe, immediate type. Common choices include cephalexin, taken twice daily for 10 days.
If you’ve had a severe allergic reaction to penicillin, your doctor will avoid that entire antibiotic family and prescribe something from a completely different class. Options include clindamycin or a macrolide antibiotic like azithromycin. However, because resistance to these drugs is rising, your doctor may want to confirm the bacteria respond to the chosen antibiotic.
Why the Full 10 Days Matter
Most people start feeling noticeably better within two to three days of starting antibiotics. That improvement can make it tempting to stop taking the medicine early, but feeling better doesn’t mean the infection is gone. The bacteria can still be present even after symptoms fade, and cutting the course short increases the chance of the infection coming back.
Completing the full course also protects against a rare but serious complication called rheumatic fever, an inflammatory condition that can damage the heart. Rheumatic fever typically develops one to five weeks after a strep infection, and adequate antibiotic treatment is the primary way to prevent it. This is one of the key reasons strep throat is treated with antibiotics at all, since the sore throat itself would eventually resolve on its own in most cases.
Pain Relief While Antibiotics Work
Antibiotics kill the bacteria, but they don’t directly relieve the sore throat. For pain and fever, ibuprofen (Advil, Motrin) and acetaminophen (Tylenol) are the standard recommendations. Both are safe for adults and children when used at appropriate doses. Aspirin should not be given to children or teenagers because of its link to Reye’s syndrome, a rare but potentially life-threatening condition.
In some cases, particularly when throat pain is severe, a doctor may offer a single dose of a corticosteroid like dexamethasone. Research shows this increases the chance of complete pain resolution within 24 to 48 hours and shortens the time to initial relief. A one-time dose doesn’t carry significant side effects. This isn’t routine at every clinic, but it’s worth asking about if swallowing is extremely painful.
Beyond medication, soft foods, plenty of fluids, and rest all help. Warm broths, cold popsicles, and cool drinks can soothe the throat while you wait for the antibiotic to take full effect.
How Quickly You Stop Being Contagious
One of the most practical things antibiotics do is make you non-contagious fast. Within 12 hours of your first dose, you’re generally no longer able to spread strep to others. That’s the threshold most schools and workplaces use for return. Without antibiotics, strep can remain contagious for two to three weeks.
What Happens if Strep Keeps Coming Back
Some people get strep throat multiple times in a year. When this happens, doctors sometimes switch to a different antibiotic for the repeat episode, since the issue may be that the original drug didn’t fully clear the bacteria or that reinfection occurred from a close contact. The same first-line antibiotics remain effective against the bacteria themselves, so the change is more about strategy than resistance. For people with truly recurrent infections (multiple confirmed episodes per year over several years), a tonsillectomy becomes a conversation worth having with a doctor.