Cephalosporins

Cephalosporins are a group of broad-spectrum antibiotics used to treat bacterial infections. They are similar to penicillin in structure and function but have an expanded range of activity against different types of bacteria.

Structure and Function

Cephalosporins work by disrupting the cell wall synthesis of bacteria, leading to their death. They have a beta-lactam ring, which is the key structural feature responsible for their antibacterial activity. This ring binds to and inhibits enzymes involved in cell wall formation, weakening the structure of the bacterial cell and making it more susceptible to destruction by the immune system.

Generations of Cephalosporins

Cephalosporins are categorized into generations based on their spectrum of activity and when they were developed. There are four generations of cephalosporins, each with increasing activity against a broader range of bacteria.

First Generation Cephalosporins

First-generation cephalosporins have activity against gram-positive bacteria, such as Staphylococcus aureus and Streptococcus pneumoniae. They are often used for skin and soft tissue infections, urinary tract infections, and surgical prophylaxis.

Second Generation Cephalosporins

Second-generation cephalosporins have a broader spectrum of activity, including some gram-negative bacteria in addition to gram-positive coverage. They are used for respiratory tract infections, otitis media, and certain types of bacterial meningitis.

Third Generation Cephalosporins

Third-generation cephalosporins have expanded coverage against gram-negative bacteria, making them useful for treating more serious infections such as hospital-acquired pneumonia, complicated intra-abdominal infections, and certain types of meningitis.

Fourth Generation Cephalosporins

Fourth-generation cephalosporins have an even broader spectrum of activity, including extended coverage against gram-negative bacteria and some activity against certain multi-drug resistant organisms. They are used for complicated urinary tract infections, septicemia, and certain types of bacterial meningitis.

Side Effects and Precautions

Common side effects of cephalosporins include allergic reactions, diarrhea, and nausea. It is important to inform your healthcare provider about any allergies to penicillin or other antibiotics before taking cephalosporins. Additionally, individuals with kidney problems should be cautious when using cephalosporins as they are primarily eliminated through the kidneys.

Study Guide

1. What is the mechanism of action of cephalosporins?
2. List the four generations of cephalosporins and their respective spectrum of activity.
3. What are the common side effects of cephalosporins?
4. When are first-generation cephalosporins typically used?
5. What precautions should individuals with kidney problems take when using cephalosporins?