What is the Difference Between Ampicillin and Amoxicillin

The main difference between ampicillin and amoxicillin is that ampicillin is given intravenously or intramuscularly whereas amoxicillin is preferred as an oral agent.

Ampicillin and amoxicillin are two antibiotics important in treating various bacterial infections. Generally, both are beta-lactam antibiotics in the penicillin group. They prevent the formation of the bacterial cell wall, leading to the death of bacteria.

Key Areas Covered

1. What is Ampicillin
   • Definition, Characteristics, Importance
2. What is Amoxicillin
   • Definition, Characteristics, Importance
3. Similarities Between Ampicillin and Amoxicillin
   • Outline of Common Features
4. Difference Between Ampicillin and Amoxicillin
   • Comparison of Key Differences

Key Terms

Amoxicillin, Ampicillin

What is Ampicillin

Ampicillin is an antibiotic important in treating bacterial infections such as respiratory tract infections, urinary tract infections, meningitis, salmonellosis, and endocarditis. Its routes of administration include oral, intramuscular, and intravenous administration. The common side effects of the drug include nausea, rash, and diarrhea.

Figure 1: Ampicillin

Ampicillin is also important in treating bacterial infections of both gram-positive and gram-negative bacteria. It is a broad-spectrum antibiotic that helps to treat infections of gram-positive bacteria including Streptococcus pneumoniae, Streptococcus pyogenes, some isolates of Staphylococcus aureus (but not penicillin-resistant or methicillin-resistant strains), Trueperella, and some Enterococcus.

What is Amoxicillin

Amoxicillin is another antibiotic important in treating bacterial infections. middle ear infection, strep throat, pneumonia, skin infections, and urinary tract infections. The main route of drug delivery is the oral route and the medication is available in capsules, suspensions, and tablets. Nausea and rash are common symptoms of amoxicillin.

Figure 2: Amoxicillin

Moreover, amoxicillin is a penicillin class of drug, structurally similar to ampicillin. Generally, this causes a higher concentration of the drug in blood and urine. Amoxicillin diffuses easily into tissues and body fluids. It will cross the placenta and excretes into breast milk.

Similarities Between Ampicillin and Amoxicillin

• Ampicillin and amoxicillin are two groups of beta-lactam antibiotics.
• They are important in treating bacterial infections. Both treat Gram-positive and Gram-negative bacteria.
• They prevent the formation of the bacterial cell wall; hence, bacteria eventually die.
• Both are penicillin-group antibiotics.

Difference Between Ampicillin and Amoxicillin

Definition

Ampicillin refers to a semi-synthetic form of penicillin used to treat infections of the urinary and respiratory tracts while amoxicillin refers to a semi-synthetic penicillin closely related to ampicillin and with similar properties but more readily absorbed when taken orally.

Route

Generally, ampicillin is given intravenously or intramuscularly while amoxicillin is preferred as an oral agent.

Dosage

The dosage of ampicillin is 500 mg of ampicillin every 6 hours for 10-14 days while the dosage of amoxicillin is 500 mg of amoxicillin 3 times a day for 10 days.

Duration

Ampicillin may be taken 10-14 days while amoxicillin may be taken 7-10 days.

Types of Infections

Ampicillin is important in treating genitourinary tract infections, respiratory tract infections, gastrointestinal tract infections, etc. while amoxicillin is important in treating ear infections, urinary tract infections, skin infections, lower respiratory tract infections, etc.

Side Effects

The common side effects of ampicillin include nausea, vomiting, stomach pain, diarrhea, rash, swollen, black, “hairy” tongue, vaginal itching, or discharge while the common side effects of amoxicillin include abdominal or stomach cramps or tenderness, back, leg, or stomach pains, black, tarry stools, blistering, peeling, or loosening of the skin, bloating, blood in the urine, bloody nose, and chest pain.

Conclusion

In brief, ampicillin and amoxicillin are two types of beta-lactam antibiotics in the group of penicillin drugs. Both types of antibiotics prevent the formation of the cell wall, and eventually, this leads to the cell death of bacteria. Ampicillin is given intravenously and intramuscularly while amoxicillin is given orally. In addition, ampicillin helps in treating genitourinary tract infections, respiratory tract infections, and gastrointestinal tract infections. Amoxicillin, on the other hand, is important in treating ear infections, urinary tract infections, and skin infections. Therefore, the main difference between ampicillin and amoxicillin is their type of treatment.

References:

1. “Ampicillin Uses, Side Effects & Warnings.” Drugs.com
2. “Amoxicillin: Uses, Dosage, Side Effects, Warnings.” Drugs.com.

Image Courtesy:

1. “Ampicillin structure” By User:Mysid – Own work (Public Domain) via Commons Wikimedia
2. “Amoxicillin” By Fvasconcellos – Own Work (Public Domain) via Commons Wikimedia