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While amoxicillin and penicillin are both antibiotics, they have slightly different uses. 

What is Amoxicillin? 

Amoxicillin is a penicillin-like antibiotic used to treat bacterial infections. 


  • Pneumonia
  • Tonsillitis
  • Bronchitis
  • Lung infections
  • Ear infections
  • Infections of the urinary tract (urinary tract infections, or UTIs)
  • Ulcers

What is Penicillin? 

Penicillin (penicillin G, benzylpenicillin) is another antibiotic used to treat bacterial infections.


  • Respiratory tract infections
  • Scarlet fever (scarlatina)
  • Skin infections
  • Tooth infections


Amoxicillin can treat a wider range of bacterial infections than penicillin. Only penicillin can be used to treat scarlet fever and amoxicillin can be used for urinary tract infections and ulcers. There are no name brand versions of penicillin; further, it is only available in an oral tablet or solution, as opposed to the oral extended-release tablet and chewable tablet version that amoxicillin is also available in. 


Both of the drugs can rid the body of harmful bacterial infections, such as upper respiratory tract infections, mild skin infections, and tooth infections. The side effects of both are quite similar, too, and include diarrhea, dizziness, heartburn, sleep problems, abdominal pain, nausea, and vomiting, among other sensations. 

Disclaimer: this article does not constitute or replace medical advice. If you have an emergency or a serious medical question, please contact a medical professional or call 911 immediately. To see our full medical disclaimer, visit our Terms of Use page.

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