Difference Between Amoxicillin and Penicillin (With Table)

If you’ve ever had a bacterial infection, a penicillin or amoxicillin antibiotic may have been prescribed to you. Many people have been prescribed these penicillin-like drugs. Amoxicillin and penicillin are both antibiotics that treat respiratory, gastrointestinal, eye, nose, and throat infections, respectively.

Amoxicillin vs Penicillin

The main difference between amoxicillin and penicillin is that the antibiotic amoxicillin is generally more efficient against a broader range of bacteria. On the other hand, Amoxicillin and penicillin are both antibiotics classified as penicillins, and they are used to treat bacterial infections of the respiratory system, skin, nose, and other organs. These antibiotics are highly effective when applied to the infected area of the body.

Among the antibiotics in this class are amoxicillin (Unasyn), piperacillin (Pipracil), and ticarcillin (Ticacillin). Accomplices such as ticarcillin (Pipracil), ampicillin (Unasyn), and piperacillin (Pipracil) also belong to the penicillin family (Ticar). Because of their capacity to prevent bacteria from creating barriers around themselves, antibiotics belonging to the penicillin group do not kill bacteria immediately after they are taken down.

Antibiotics containing penicillin treat infections caused by bacteria in the eardrum, nose, intestines, bladder, and kidney, among other organs and structures. It is also used to treat pneumonia, blood infections (sepsis), mild gonorrhoea, meningitis, endocarditis, and other conditions. Penicillin derivatives have been developed that are effective against a broader spectrum of bacteria than the original life-saving antibiotic penicillin itself.

Comparison Table Between Amoxicillin and Penicillin

Parameters of ComparisonAmoxicillinPenicillin
Effective medicine onBacterial Overwhelm.An Infection with Bacteria
PriceAmoxicillin is Cheap in price.Penicillin is Cheap in price.
EffectivenessBacteria of a Wider VarietyBacteria with a Broad Spectrum
Side EffectsAbdominal pain, dizziness, and nausea are just a few symptoms that some people experience when using this medication.Discomforts such as dizziness, heartburn, sleeplessness, and nausea are possible side effects.
Effective against bacteria likeHepatitis A, Helicobacter pylori, Escherichia coli O157:H7, Prevotella mirabilis, Escherichia coli O157:H7, and othersThere are four groups of streptococci: Group A streptococci, Group B, Group C, and Group G streptococci.

What is Amoxicillin?

In 1958, amoxicillin was discovered, and it was utilized in medicine for the first time in 1972—the WHO has classified it as a life-saving medication. About paediatrics, it is a common antibiotic. A common antibiotic in the United States is amoxicillin. Almost 31 million prescriptions were written for it in the United States in 2018, making it the fifteenth most prescribed medication.

Amoxicillin is an antibiotic that can treat a wide variety of bacterial infections. Only a few of these include infections of the eardrum or tongue, pneumonia, inflammatory illnesses, and urinary tract infections.

Amoxicillin is almost always given orally since the digestive system absorbs it. It is easier for children to take amoxicillin than conventional penicillin because children are more prone to ear and throat infections, which amoxicillin successfully treats.

It is used to treat severe otitis media, streptococcal pharyngitis, pneumonia, and skin conditions. Amoxicillin is also used to treat Salmonella infections, Lyme disease, and genital infections.

Erythema and nausicaasis are two common symptoms. Fungal infections and diarrhoea are also more likely when clavulanic acid is combined. Penicillin should not be used by those who are allergic to it. While it is safe to use in renal patients, the dosage may be lowered. While pregnant or breastfeeding, it appears to be safe to use. Beta-lactam antibiotics, such as amoxicillin, are the class in which it resides.

What is Penicillin?

Amoxicillin was discovered in 1958, and it was used in medicine for the first time in 1972 when the FDA approved it. A life-saving medicine by the World Health Organization has been designated for use. Children have frequently been prescribed tetracycline as an antibiotic. Is amoxicillin a standard treatment for a wide range of illnesses in the United States?. In 2018, about 31 million prescriptions were written for it in the United States, ranking it as the fifteenth most commonly prescribed medication.

Infections of the eardrum or tongue, pneumonia, inflammatory disorders, and urinary tract infections are just a few conditions that might occur. While most patients receive it orally, it can also be delivered intravenously in some cases.

As a result of the high absorption of amoxicillin by the digestive system, it is virtually always administered orally. Because children are more susceptible to ear and throat infections, which amoxicillin effectively treats, it is easier for children to take amoxicillin than it is for adults to take regular penicillin.

Severe otitis media, streptococcal pharyngitis, pneumonia, and skin disorders are all treated with this medication. It is also used to treat other illnesses such as Salmonella infections, Lyme disease, and vaginal infections.

Two of the most prevalent symptoms are erythema and nausicaasis. When clavulanic acid is used in conjunction with other medications, it increases the likelihood of fungal infections and diarrhea. When used in renal patients, it is generally considered safe; however, the dosage may need to be reduced. Amoxicillin is classified as a beta-lactam antibiotic, which means it belongs to that class.

Main Difference Between Amoxicillin and Penicillin

  1. Even though the side effects of amoxicillin and penicillin are nearly identical, amoxicillin is more likely to produce an allergic reaction than penicillin.
  2. Additionally, amoxicillin can be used with other medications to treat genitourinary infections, acute, uncomplicated gonorrhea, and H. pylori eradication. Genitourinary infections, symptomatic, uncomplicated gonorrhea, and eradication of H. pylori are all conditions that can be treated with amoxicillin.
  3. The antibiotic penicillin, discovered in 1928, was widely used during World War II due to its widespread use. Amoxicillin was discovered in 1958, and it was not used in medicine until 1972 when it was approved for use in the United States.
  4. Symptoms of rheumatic fever or chorea, viral endocarditis, bacterial meningitis, and dental concerns such as gum disease can all be controlled with penicillin.
  5. Amoxicillin has a broader spectrum of activity against bacteria, while penicillin has a medium spectrum against germs.


There are generic antibiotics like amoxicillin and penicillin, and drugs with generic names are called generics. In terms of dosage, intended use, side effects, and administration, these generics are identical to their name-brand counterparts in every way.

With other antibiotics, the effects of amoxicillin and penicillin are nearly the same. Drug-chemical interactions are defined as instances in which two substances interact. This could be hazardous or impair the medication’s efficacy if done incorrectly. When it comes to brand-name medications, generic medicines are often less expensive. Consequently, penicillin & generic amoxicillin are likely less expensive than brand name amoxicillin

Pre-authorization is not required for most health insurance coverage to cover amoxicillin and penicillin. On the other hand, prior approval may be necessary for brand-name drugs.


  1. https://europepmc.org/article/med/10718859
  2. https://pubs.rsc.org/en/content/articlehtml/2012/gc/c2gc36158b