Antibiotic Types: Classes of Antibiotics to Fight Infection

The discovery of antibiotics is one that continues to benefit people all over the world. Infections that used to be considered a death sentence are now cured easily with a round of antibiotic therapy. However, antibiotics are not a one size fits all treatment for infections. Different types of antibacterial respond to different antibiotic types, so it’s important to know about the classes of antibiotics used in treating infections. The seven major classes of antibiotics are penicillins, cephalosporins, macrolides, fluoroquinolones, sulfonamides, tetracycline, arminoglycosides. In this four-part series, you’ll learn about each of these antibiotic types and how they are used.

Antibiotic Types: Penicillin Drugs

Penicillin drugs are very widely used in the medical field, as they are able to treat a wide number of infections. Penicillin works to kill bad bacteria by weakening the cell wall of the bacteria and causing cell death due to increased pressure within the cell. Drugs in this class include Benzylpenicillin, Procaine, Benzathine, and Phenoxymethylpenicillin. Benzylpenicillin is used to treat a number of infections including gonorrhea, meningitis, cellulitis, and syphilis. This type of Penicillin is delivered parenterally to prevent disintegration of the drug from the acid contained in the stomach. Procaine benzylpenicillin contains a local anesthetic and is given via intramuscular injection. The local ansethestic helps to ease the pain of receiving an injection via one of the large muscles in the body. Benzathine is also given via intramuscular injection. It is used to prevent rheumatic fever and to treat syphilis when it is in its early stages. Phenoxymethylpenicillin is given orally to treat conditions such as skin infections and inflammation of the tonsills.

Antibiotic Types: Cephalosporin Drugs

Cephalosporins are very commonly prescribed to treat infections. They work very similarly to penicillin antibiotics because they contain beta-lactam, which inhibits the development of the bacterial cell wall. This results in death of the bacterial cells, eliminating infection. Cephalosporins are classified into first, second, third, and fourth generation categories. First generation cephalosporins are used for infections that are staphylococcal or streptococcal in nature. Examples of first generation cephalosporin antibiotics include Cephalexin, Cefazolin, and Cefaxdroxil. Second generation cephalosporins are used to treat infections of the ears, sinuses, and upper respiratory tract. Common second generation cephalosporins include Cefaclor and Cefprozil. Third generation cephalosporins are considered to be broad-spectrum antibiotics. These drugs can be used to treat gonorrhea and other infections. Examples of third generation cephalosporins include Ceftibuten and Cefotaxime. Fourth generation cephalosporins are used for treating meningitis because they can cross the blood-brain barrier. Examples include Cefpirome and Cefozopran.

In the next article in this series, you’ll learn about the macrolide and fluoroquinolone antibiotic types.

Reference Materials

eMedicineHealth. “Types of Antibiotics.” Retrieved November 24, 2008 from Types of Antibiotics

Suite 101 Bacteriology Channel. “MOA of Penicillin Antibiotics.” Retrieved November 24, 2008 from MOA of Pencillin Antibiotics

eMedExpert. “Antibiotics: Cephalosporins.” Retrieved November 24, 2008 from Antibiotics: Cephalosporins