Cefmetazole

Cefmetazole is a second-generation cephalosporin antibiotic with a broad spectrum of activity against both Gram-positive and Gram-negative bacteria. It is particularly noted for its effectiveness against Enterobacteriaceae, a family of bacteria that includes many pathogenic species responsible for various infections. Cefmetazole is administered intravenously and is commonly used in the treatment of infections in the lower respiratory tract, skin and skin structure infections, urinary tract infections, and pelvic inflammatory disease. It is also used as a prophylactic agent in certain surgical procedures to prevent postoperative infections.

Mechanism of Action

Cefmetazole works by inhibiting the synthesis of the bacterial cell wall, leading to cell lysis and death. It binds to penicillin-binding proteins (PBPs) located inside the bacterial cell wall, interfering with the final transpeptidation step of peptidoglycan synthesis. Peptidoglycan is a critical component of the bacterial cell wall, and its disruption results in the weakening and eventual rupture of the cell wall, causing bacterial cell death.

Pharmacokinetics

After intravenous administration, cefmetazole is distributed widely throughout the body, including to the gallbladder, liver, and kidneys. It is able to penetrate into various body fluids, including bile, making it effective in treating infections in these areas. The drug is primarily excreted unchanged in the urine, and to a lesser extent in the bile.

Indications

Cefmetazole is indicated for the treatment of the following infections when caused by susceptible strains of bacteria:

• Lower respiratory tract infections
• Skin and skin structure infections
• Urinary tract infections
• Pelvic inflammatory disease
• Intra-abdominal infections
• Septicemia
• Bone and joint infections

It is also used as a prophylactic agent in certain surgical procedures, such as abdominal, gynecological, or orthopedic surgeries, to prevent postoperative infections.

Adverse Effects

Common adverse effects of cefmetazole include gastrointestinal disturbances such as nausea, vomiting, and diarrhea. Allergic reactions, ranging from rash to anaphylaxis, have been reported but are rare. As with other cephalosporins, there is a potential for cross-reactivity in patients with a history of penicillin allergy.

Contraindications

Cefmetazole is contraindicated in patients with a known allergy to cephalosporin antibiotics. Caution is advised in patients with a history of penicillin allergy due to the potential for cross-reactivity.

Drug Interactions

Cefmetazole may interact with other medications, such as aminoglycoside antibiotics, increasing the risk of nephrotoxicity. It may also interfere with certain types of lab tests, including Coombs' test.

Conclusion

Cefmetazole is a valuable second-generation cephalosporin with a broad spectrum of activity against both Gram-positive and Gram-negative bacteria. Its ability to penetrate into various body fluids makes it effective in treating a wide range of infections. However, like all antibiotics, it should be used judiciously to prevent the development of antibiotic resistance.