Cephudder ointment

Indications

• Skin and soft tissue infections
• Respiratory tract infections
• Bone and joint infections
• Endocarditis
• Urinary tract infections

Dosage

Children: Refer to the BNF for Children for specific dosing information.

Adults: Refer to the BNF for specific dosing information.

Mechanism of action

The bactericidal activity of cephapirin results from the inhibition of cell wall synthesis via its affinity for penicillin-binding proteins (PBPs). This inhibition prevents cross-linkage of peptidoglycan chains, essential for bacterial cell wall strength and rigidity. As a result, cell division and growth are inhibited, leading to lysis and elongation of susceptible bacteria, particularly those that are rapidly dividing.

Pharmacodynamics

Cephapirin exhibits a wide spectrum of activity against various gram-positive and some gram-negative organisms. It demonstrates increased resistance to beta-lactamases compared to penicillins, allowing effective treatment of staphylococcal infections, though it is ineffective against methicillin-resistant staphylococci.

Pharmacokinetics

Cephapirin is administered parenterally and is distributed widely in body tissues and fluids. It has a relatively short half-life, necessitating frequent dosing to maintain therapeutic levels. The drug is primarily eliminated through the kidneys, and renal function can significantly affect its clearance.

Contra-indications

• Hypersensitivity to cephalosporins or penicillins
• History of severe allergic reactions to beta-lactam antibiotics

Adverse effects

• Allergic reactions including rash, itching, and anaphylaxis
• Gastrointestinal disturbances such as nausea, vomiting, and diarrhea
• Hematologic reactions including leukopenia and thrombocytopenia
• Renal toxicity
• Superinfection with non-susceptible organisms

Interactions

• Probenecid may increase levels of cephapirin
• Concurrent use with aminoglycosides may enhance nephrotoxicity

Precautions

• Use with caution in patients with renal impairment
• Monitor for signs of allergic reactions during therapy
• Consider potential cross-reactivity in patients with penicillin allergies

Pregnancy

Cephapirin is categorized as pregnancy category B, indicating no evidence of risk in human studies, but should be used only if clearly needed.

Breast-feeding

Cephapirin is excreted in breast milk; caution should be exercised when administering to nursing mothers.

Storage

Store in a cool, dry place away from direct sunlight. Protect from moisture.

Formulations

• Injectable solution
• Powder for reconstitution

Mechanism of action

The bactericidal activity of cephapirin results from the inhibition of cell wall synthesis via affinity for penicillin-binding proteins (PBPs). ... VERY RESISTANT TO ACTION OF PENICILLINASE, FOR WHICH IT IS BOTH COMPETITIVE & NONCOMPETITIVE INHIBITOR ... IT DOES NOT SUPPRESS BREAKDOWN OF PENICILLIN G BY STAPHYLOCOCCAL PENICILLINASE. CEPHALOSPORIN C & ITS SEMISYNTHETIC CONGENERS INDUCE SYNTH OF PENICILLINASE BY B CEREUS & STAPH AUREUS. /CEPHALOSPORIN C/ ... ENZYME ACTING SPECIFICALLY ON CEPHALOSPORIN C TO DESTROY ITS ANTIBACTERIAL ACTIVITY. THIS SUBSTANCE, CEPHALOSPORINASE IS ALSO BETA-LACTAMASE. MOST PREPN OF ENZYME ALSO EXHIBIT PENICILLINASE ACTIVITY, & SOME MICROORGANISMS PRODUCE ONE BETA-LACTAMASE THAT ACTS ON BOTH PENICILLIN & CEPHALOSPORINS. /CEPHALOSPORIN C/ Bactericidal; action depends on ability to reach and bind pencillin-binding proteins located in bacterial cytoplasmic membranes; cephalosporins inhibit bacterial septum and cell wall synthesis, probably by acylation of membrane-bound transpeptidase enzymes. This prevents cross-linkage of peptidoglycan chains, which is necessary for bacterial cell wall strength and rigidity. Also, cell division and growth are inhibited, and lysis and elongation of susceptible bacteria frequently occur. Rapidly dividing bacteria are those most susceptible to the action of cephalosporins. /Cephalosporins/

Pharmacodynamics

Cephapirin is a first-generation cephalosporin that has a wide spectrum of activity against gram-positive and gram-negative organisms. Cephapirin is more resistant to beta-lactamases than are the penicillins and so is effective against staphylococci, with the exception of methicillin-resistant staphylococci.