An antibiotic, usually amoxicillin or penicillin, is used to treat tonsillitis caused by strep bacteria. Although tonsillitis caused by strep bacteria usually will go away on its own, antibiotics are used to prevent the complications, such as rheumatic fever, that can result from untreated strep throat.
What to think about
If antibiotics are prescribed, be sure you take them exactly as directed by your doctor until the medicine is gone. Even if the symptoms go away completely before the prescription is gone, all pills should be taken as directed to make sure the infection is completely destroyed. Bacteria can become resistant to the antibiotics used to treat tonsillitis (antibiotic resistance) if prescriptions aren't taken as directed or if they are prescribed when they aren't needed.