Mechanism of Action
Aztreonam contains a monocyclic beta-lactam ring. Its uniqueness lies in its high resistance to beta-lactamases produced by gram-negative bacteria. The drug disrupts bacterial cell wall synthesis, leading to cell death. Notably, it is degraded by beta-lactamases of gram-positive bacteria and anaerobes, which dictates its narrow spectrum of activity.
Pharmacological Effects
The drug exhibits significant activity against Escherichia coli, Pseudomonas aeruginosa, Proteus spp., Klebsiella spp., Haemophilus influenzae, as well as gonococci and meningococci. Aztreonam has no activity against gram-positive flora and anaerobic microorganisms (including Bacteroides).
Indications
Aztreonam is a reserve drug. Its key advantage is low cross-allergenicity, allowing its use in patients with severe penicillin allergies. Main indications: lower respiratory tract infections (including nosocomial pneumonia), intra-abdominal infections, pelvic infections, severe urinary tract infections, skin and soft tissue infections, bone and joint infections, and systemic infections (sepsis, meningitis).
Adverse Effects
Potential adverse effects include gastrointestinal dyspepsia, skin allergic reactions, and headaches. Local reactions, such as phlebitis at the injection site, are frequently observed with parenteral administration.
Administration Guidelines
The drug is administered parenterally (IV or IM) as a bolus or infusion. The single dose is 0.5–2.0 g administered every 8–12 hours. The maximum daily dose is 8.0 g. Aztreonam is indispensable when other antibiotics are ineffective against gram-negative infections.