- Cephalosporins are one of the most widely used classes of antibiotics in the world. These drugs belong to the beta-lactam group and are closely related to penicillins. Cephalosporins are known for their broad-spectrum activity and high safety profile, in this blog we will discuss Classification of Cephalosporins.
- We will also explore , their different generations, and their clinical uses. The classification is based on the generation and route of administration (oral or parenteral).
Table of Contents
🔬 What Are Cephalosporins?
Cephalosporins are bactericidal antibiotics, meaning they kill bacteria by inhibiting cell wall synthesis. They are used to treat a wide range of infections including respiratory tract infections, urinary tract infections, skin infections, and more.
Over time, cephalosporins have been divided into generations based on their spectrum of activity. Newer generations have better gram-negative coverage and increased resistance to beta-lactamases.
📊 Classification of Cephalosporins
Cephalosporins are classified into four generations, and each generation contains drugs used either orally or parenterally (injections).
🧪 First Generation Cephalosporins
These drugs are more effective against gram-positive bacteria and are commonly used for skin and soft tissue infections.
- Oral:
- Cephalexin
- Cefadroxil
- Parenteral:
- Cefazolin
✅ Common Uses: Skin infections, surgical prophylaxis, streptococcal pharyngitis
🧪 Second Generation Cephalosporins
These have better gram-negative coverage than first generation, and are often used for respiratory and ENT infections.
- Oral:
- Cefaclor
- Cefuroxime axetil
- Cefprozil
- Parenteral:
- Cefuroxime
- Cefoxitin
✅ Common Uses: Otitis media, sinusitis, bronchitis, abdominal infections (especially Cefoxitin)
🧪 Third Generation Cephalosporins
This generation has even broader gram-negative activity and good CNS penetration. They are often used in hospitals.
- Oral:
- Cefixime
- Cefpodoxime proxetil
- Cefdinir
- Ceftibuten
- Ceftamet pivoxil
- Parenteral:
- Cefotaxime
- Ceftriaxone
- Ceftizoxime
- Ceftazidime
- Cefoperazone
✅ Common Uses: Pneumonia, meningitis (Ceftriaxone), typhoid, gonorrhea, severe urinary tract infections
🧪 Fourth Generation Cephalosporins
These are the most advanced in the cephalosporin class. They are resistant to beta-lactamase enzymes and have broad-spectrum action.
- Parenteral Only:
- Cefepime
- Cefpirome
✅ Common Uses: Nosocomial infections, febrile neutropenia, multidrug-resistant infections
🧪 Fifth Generation Cephalosporins
This latest generation of cephalosporins is specially developed to treat multi-drug resistant bacteria, including MRSA. Unlike earlier generations, they offer a unique spectrum that bridges gram-positive and some gram-negative pathogens.
- Parenteral Only:
- Ceftaroline fosamil
- Ceftobiprole (not yet widely approved in all countries)
✅ Common Uses:
- MRSA-related skin and soft tissue infections
- Community-acquired pneumonia
- Complicated bacterial infections when resistance is suspected
💊 Clinical Uses
Cephalosporins: Drug of Choice Based on Specific Infections
Cephalosporins are a large group of beta-lactam antibiotics divided into generations based on antimicrobial spectrum. Each generation is useful in specific infections, and some are considered drugs of choice in current clinical practice.
First Generation
- Cefazolin: DOC for surgical prophylaxis and susceptible gram-positive skin infections.
Second Generation
- Cefuroxime: Used in upper respiratory tract infections and surgical prophylaxis for abdominal or gynecological procedures.
Third Generation
- Ceftriaxone:
- DOC for gonorrhea, typhoid fever, bacterial meningitis, E. coli sepsis, Haemophilus, and Proteus infections.
- Ceftazidime:
- DOC for Pseudomonas infections, including febrile neutropenia and melioidosis (caused by Burkholderia pseudomallei).
- Ceftizoxime: DOC for Bacteroides fragilis infections.
Fourth Generation
- Cefepime: Preferred in hospital-acquired pneumonia, febrile neutropenia, sepsis, and resistant infections due to broad coverage and β-lactamase stability.
Fifth Generation
- Ceftaroline and Ceftobiprole:
- DOC for community-acquired pneumonia and MRSA infections.
- Ceftobiprole is also active against Pseudomonas
| Generation | Common Drugs | Route | Typical Uses |
|---|---|---|---|
| 1st | Cephalexin, Cefazolin | Oral, IV | Skin infections, dental infections |
| 2nd | Cefuroxime, Cefaclor | Oral, IV | Sinusitis, bronchitis, abdominal infections |
| 3rd | Cefixime, Ceftriaxone | Oral, IV | Typhoid, UTI, meningitis, gonorrhea |
| 4th | Cefepime | IV only | Hospital-acquired and resistant infections |
| 5th | Ceftaroline, Ceftobiprole | IV only | MRSA infections, severe pneumonia, soft tissue infections |
⚠️ Precautions and Side Effects
While cephalosporins are generally safe, side effects may include:
- Allergic reactions (especially in penicillin-sensitive patients)
- Diarrhea
- Nausea and vomiting
- Rarely, seizures at high doses
🧠 Trivia Time!
- Cephalosporins were discovered from a fungus called Acremonium (formerly Cephalosporium) in 1945 by Giuseppe Brotzu in Italy.
- Ceftriaxone is one of the most prescribed antibiotics globally due to its long half-life and broad activity.
References
- K.D. Tripathi, Essentials of Medical Pharmacology, 7th Edition. Jaypee Brothers Medical Publishers, Chapter-51 Beta-Lactam Antibiotics. Accessible at: Jaypee Digital
- Sparsh Gupta & Garg, Review of Pharmacology, 15th Edition. Jaypee Brothers Medical Publishers.
- Goodman & Gilman’s, The Pharmacological Basis of Therapeutics, 12th Edition. McGraw-Hill Education. See: Chapter 53, “Penicillins, Cephalosporins and Other β-Lactam Antibiotics.”