Cefazoline

Cefazolin, also known as cefazoline or by its brand name Ancef, is a type of antibiotic belonging to the class known as first-generation cephalosporins. It is widely used in the treatment and prevention of a variety of bacterial infections. Cefazolin works by inhibiting the synthesis of the bacterial cell wall, leading to the death of the bacteria.

Medical Uses

Cefazolin is primarily indicated for the treatment of bacterial infections caused by susceptible organisms. These infections include skin and soft tissue infections, respiratory tract infections, urinary tract infections, bone and joint infections, and septicemia. It is also commonly used as a prophylactic agent in surgical procedures to prevent postoperative infections.

Mechanism of Action

The mechanism of action of cefazolin involves the inhibition of bacterial cell wall synthesis. It binds to specific penicillin-binding proteins (PBPs) located inside the bacterial cell wall, thereby inhibiting the final transpeptidation step of peptidoglycan synthesis. This action leads to the weakening of the cell wall and eventually causes cell lysis and death.

Pharmacokinetics

Cefazolin is administered either intramuscularly (IM) or intravenously (IV). It is not well absorbed from the gastrointestinal tract, which is why it is not available in oral form. After administration, cefazolin is widely distributed throughout the body, including to the bones, heart, gallbladder, and liver. It is excreted primarily by the kidneys.

Side Effects

Common side effects of cefazolin include nausea, vomiting, diarrhea, and rash. Less frequently, it can cause more serious adverse effects such as allergic reactions, anaphylaxis, and Clostridium difficile-associated diarrhea. As with all antibiotics, prolonged use of cefazolin can lead to the overgrowth of non-susceptible organisms, including fungi.

Contraindications

Cefazolin is contraindicated in patients with a known allergy to cephalosporins or penicillins due to the potential for cross-reactivity. Caution is advised in patients with renal impairment, as dosage adjustment may be necessary.

Comparison with Other Antibiotics

Cefazolin, as a first-generation cephalosporin, has a narrower spectrum of activity compared to later-generation cephalosporins. It is particularly effective against gram-positive bacteria and some gram-negative bacteria. However, it is less effective against more resistant organisms, which may be better treated with more advanced cephalosporins or other classes of antibiotics.