Aztreonam
**Aztreonam** is a monobactam injectable antibiotic primarily utilized for its strong activity against a variety of aerobic and facultative gram-negative bacteria. * **Spectrum of Activity:** Highly effective against *Citrobacter*, *Enterobacter*, *E. coli*, *Klebsiella*, *Proteus*, *Pseudomonas*, and *Serratia*. * **Clinical Pearl:** It is **not** clinically efficacious against gram-positive or anaerobic bacteria. * **Clinical Utility:** Often considered for serious gram-negative infections when traditional choices like aminoglycosides or fluoroquinolones are ineffective or relatively contraindicated (e.g., due to nephrotoxicity concerns). * Exhibits excellent tissue penetration and generally has a low toxic potential, though clinical experience and pharmacokinetic data in veterinary target species remain limited.
Mecanismo: Aztreonam is a **bactericidal** antibiotic. * It selectively binds to **penicillin-binding protein-3 (PBP-3)** in susceptible bacteria. * Binding to PBP-3 → **inhibits bacterial cell wall synthesis** → results in cell lysis and death. * It is highly stable against the hydrolytic effects of bacterial **beta-lactamases** and, unlike many other beta-lactam antibiotics, does not induce beta-lactamase activity. * **Synergy:** Can exhibit synergistic effects against *Pseudomonas aeruginosa* and other gram-negative bacilli when used concurrently with aminoglycosides.
Dosificación por especie
- Serious gram-negative infections · 30 mg/kg · IM or IV · q6-8h · Anecdotal dosing suggestion based on the human pediatric dose. Aztreonam has a shorter half-life in dogs but is about half as bound to plasma proteins compared to humans.
Las dosis son una referencia clínica para veterinarios colegiados. Confirme siempre con la ficha técnica vigente y el paciente individual.
Vías de administración
Contraindicaciones
- Documented severe hypersensitivity to aztreonam
Efectos adversos
- Hypersensitivity reactions
- Gastrointestinal effects (bacterial overgrowth, pseudomembranous colitis, diarrhea)
- Pain and/or swelling after IM injection
- Phlebitis after IV administration
- Transient increases in liver enzymes, serum creatinine, and coagulation indices
Interacciones farmacológicas
- Probenecid · Can reduce the renal tubular secretion of aztreonam, thereby maintaining higher systemic levels for a longer period of time. This potential 'beneficial' interaction requires further investigation in veterinary patients.
Monitorización
- Clinical efficacy
- Signs of toxicity or adverse effects
- Renal and hepatic function in compromised patients
Sobredosis
There is little reason for concern in patients with adequate renal function. The IV LD50 for mice is 3.3 g/kg. Hemodialysis or peritoneal dialysis may be used to clear aztreonam from the circulation.
La referencia de fármacos de VetSheet está destinada a veterinarios colegiados como apoyo a la decisión clínica, no sustituye el juicio profesional ni la ficha técnica vigente del fabricante.