Penicillin was discovered in 1928 and has been used to treat various infections since the 1940s.
Amoxicillin is a semi-synthetic penicillin that became available in 1972.
There are differences between how and when amoxicillin and penicillin are prescribed.Amoxicillin is a form of penicillin.
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AsiaVision / Getty Images
Uses of Amoxicillin vs.
Penicillin
The FDA has approved amoxicillin and penicillin to treat similar types ofbacterial infections.
Both amoxicillin and penicillin belong to the class of antibiotics called penicillins.
Amoxicillin is a generic prescription drug.
Brand-name versions include Amoxil and Larotid.Penicillin is a generic prescription drug.
There currently isnt a brand-name version of penicillin V potassium available.
Penicillin works to treat many of the same infections as amoxicillin.
Scientists continue to research new antibiotics.
Is Amoxicillin or Penicillin More Effective?
Given the similar nature of amoxicillin and penicillin, only some clinical studies have directly compared the two medications.
Research suggests, however, that amoxicillin is more effective for certain types of bacteria compared with penicillin.
An older study investigated the difference between oral amoxicillin and injectable penicillin for pneumonia in children.
Another study compared the effectiveness of amoxicillin vs. penicillin for pneumonia.
In this study, researchers found amoxicillin more effective than penicillin.
Overall, these studies suggest relative efficacy between the two products.
However, amoxicillin may provide better outcomes for certain infections or strains of bacteria.
Dosage
Both amoxicillin and penicillin are available in a variety of dosage forms and strengths.
No differences in effectiveness exist between the various dosage forms of the same medication.
Doing so can increase the risk of the infection returning even worse, making it more challenging to treat.
Side Effects and Safety
Like all drugs, amoxicillin and penicillin may cause similar side effects.
As such, closely monitor yourself or a loved one while taking amoxicillin or penicillin.
In these cases, diarrhea could last up to two months and require treatment.
Taking amoxicillin or penicillin can infrequently lead to a severe allergic reaction calledanaphylaxis.
Symptoms of an allergic reaction include rash, difficulty breathing, and swelling in the face or throat.
Amoxicillin is more likely to cause a rash, which is not necessarily a sign of an allergy.
Allergy Warning
You should not take amoxicillin if you’re allergic to penicillin, or vice versa.
Exhibiting an allergy to one makes it likely you’ll be allergic to the other.
Summary
Penicillins are a class of antibiotics used against a wide range of bacteria.
Both penicillin and amoxicillin are categorized as penicillin-class drugs.
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