Doctors treat strep throat with antibiotics, most commonly amoxicillin or penicillin, taken for 10 days. These two medications are the first choice because they’re effective, inexpensive, and strep bacteria haven’t developed resistance to them. Along with the antibiotic, your doctor may recommend over-the-counter pain relievers and, in some cases, a single dose of a steroid to help with throat pain.
How Strep Throat Is Confirmed
Before prescribing anything, your doctor needs to confirm that strep bacteria are actually causing your sore throat. Most offices start with a rapid strep test, which involves swabbing the back of your throat and getting results in minutes. These tests are highly accurate when they come back positive, with specificity around 96%. Sensitivity is also strong, catching roughly 99% of true infections in newer test versions.
If the rapid test comes back negative but your doctor still suspects strep, the next step depends on your age. For children over 3, guidelines recommend following up with a throat culture, which takes one to two days but is considered the gold standard. For teens and adults, a backup culture after a negative rapid test typically isn’t needed.
First-Choice Antibiotics
Amoxicillin and penicillin are the standard prescriptions. Most doctors lean toward amoxicillin for children because it tastes better in liquid form and can be given once or twice a day, making it easier to stick with. Adults typically get penicillin taken twice daily. Either way, the course lasts 10 days.
There’s also a one-shot option: a single injection of penicillin given at the doctor’s office. This eliminates the need to remember pills for 10 days, which can be useful for patients who have trouble completing a full course. The injection handles the entire treatment in one visit.
Finishing the full 10 days of oral antibiotics matters even after you feel better, which usually happens within a day or two. Stopping early increases the risk of the infection returning and raises the chance of complications.
Options If You’re Allergic to Penicillin
If you have a penicillin allergy, your doctor has several alternatives. The specific choice depends on how severe your allergy is.
- Cephalosporins (such as cephalexin or cefadroxil) are often the next choice for people whose penicillin allergy causes a mild rash rather than a serious reaction. These are related to penicillin but are generally safe for people with non-severe allergies. The course is 10 days.
- Azithromycin is a common pick for people with more serious penicillin allergies. It has the advantage of a shorter course: a higher dose on day one, then four more days at a lower dose, for five days total.
- Clindamycin is another 10-day option taken three times daily, used when other alternatives aren’t suitable.
- Clarithromycin is a 10-day, twice-daily alternative in the same drug family as azithromycin.
Pain Relief While the Antibiotic Works
Antibiotics kill the bacteria, but they don’t provide instant pain relief. Most people still have significant throat pain for the first 24 to 48 hours after starting treatment. Over-the-counter pain relievers like ibuprofen (Advil, Motrin) or acetaminophen (Tylenol) are the go-to options for managing that discomfort and bringing down fever. Ibuprofen has the added benefit of reducing inflammation in the throat.
Aspirin should not be given to children or teenagers with strep throat. It’s been linked to Reye’s syndrome, a rare but serious condition, in young people recovering from infections.
Some doctors also prescribe a single dose of a corticosteroid, typically dexamethasone, to reduce throat pain more quickly. A BMJ clinical practice guideline supports this as an option for both adults and children (age 5 and older) with acute sore throat, whether the cause is viral or bacterial. The steroid is given once, either as a pill or injection, and is meant to take the edge off severe pain rather than replace antibiotics. It’s not recommended for people with mono, weakened immune systems, or recurrent sore throats.
When You Stop Being Contagious
One of the biggest practical questions people have is when they can go back to work or send their kids back to school. You’re no longer contagious within 12 hours of taking your first dose of antibiotics. Most schools and daycares follow this same 12-hour rule, requiring children to have started treatment and be fever-free before returning.
Without antibiotics, strep throat can remain contagious for two to three weeks, even as symptoms improve. This is one of several reasons treatment matters beyond just feeling better.
Why Treatment Matters Beyond Symptom Relief
Strep throat will often resolve on its own in terms of throat pain, but the infection can trigger serious complications if left untreated. The most concerning is rheumatic fever, which can develop one to five weeks after a strep infection. Rheumatic fever causes inflammation throughout the body and can permanently damage heart valves. Severe cases require heart surgery and can be fatal.
Untreated strep can also lead to a kidney condition called post-streptococcal glomerulonephritis, where the immune system’s response to the bacteria damages the kidneys’ filtering units. Other possible complications include abscesses around the tonsils and spread of the infection to the bloodstream. A simple 10-day course of antibiotics prevents nearly all of these outcomes, which is why doctors treat strep even when symptoms are mild.