Aztreonam is poorly absorbed when given orally, so it must be administered as an intravenous or intramuscular injection (brand name Azactam), or inhaled (brand name Cayston) using an ultrasonic nebulizer. In the United States, the Food and Drug Administration (FDA) approved the inhalation form in February 2010, for the suppression of P. aeruginosa infections in people with cystic fibrosis.[11] It received conditional approval for administration in Canada and the European Union in September 2009,[11] and has been fully approved in Australia.[12]
Contraindications
Aztreonam can be safely used in people with a penicillin or cephalosporin allergy (except for people with a ceftazidime allergy as ceftazidime and aztreonam share a similar side chain).[13] It is also frequently used as an alternative to aminoglycosides because is not ototoxic or nephrotoxic.[14]
Side effects
Reported side effects include injection site reactions, rash, and rarely toxic epidermal necrolysis. Gastrointestinal side effects generally include diarrhea and nausea and vomiting. Although C. difficile infection is a possible complication of aztreonam therapy, this antibiotic is associated with a low risk of developing C. difficile infection.[15] There may be drug-induced eosinophilia. Because of the unfused beta-lactam ring there is somewhat lower cross-reactivity between aztreonam and many other beta-lactam antibiotics, and it may be safe to administer aztreonam to many patients with hypersensitivity (allergies) to penicillins and nearly all cephalosporins.[16] There is a much lower risk of cross-sensitivity between aztreonam and other beta-lactam antibiotics than within other beta-lactam antibiotics. However, there is a higher chance of cross-sensitivity if a person is specifically allergic to ceftazidime, a cephalosporin. Aztreonam exhibits cross-sensitivity with ceftazidime due to a similar side chain.[17]
Mechanism of action
Aztreonam is similar in action to penicillin. It inhibits synthesis of the bacterial cell wall, by blocking peptidoglycan crosslinking. It has a very high affinity for penicillin-binding protein-3 and mild affinity for penicillin-binding protein-1a. Aztreonam binds the penicillin-binding proteins of Gram-positive and anaerobic bacteria very poorly and is largely ineffective against them.[16] Aztreonam is bactericidal, but less so than some of the cephalosporins.[medical citation needed]
Research
Aztreonam is under consideration for human infections sustained by metallo-beta-lactamase (MBL)-producing gram-negative bacteria. In these circumstances aztreonam is combined with ceftazidime/avibactam. The combination of aztreonam and avibactam are in phase III clinical trails.[18][19] The combination of aztreonam and avibactam has demonstrated to be active against 80% of MBL isolates reaching a clinical infection resolution in 80% of MBL-infected patients.[20]
Synergism between aztreonam and arbekacin or tobramycin against P. aeruginosa has been suggested.[21]
References
^"Cayston EPAR". European Medicines Agency. 21 June 2004. Retrieved 12 July 2024.
^ abcdefghijkl"Aztreonam". The American Society of Health-System Pharmacists. Retrieved 8 December 2017.
^British national formulary : BNF 69 (69 ed.). British Medical Association. 2015. p. 381. ISBN9780857111562.
^World Health Organization (2019). Executive summary: the selection and use of essential medicines 2019: report of the 22nd WHO Expert Committee on the selection and use of essential medicines. Geneva: World Health Organization. hdl:10665/325773. WHO/MVP/EMP/IAU/2019.05. License: CC BY-NC-SA 3.0 IGO.
^World Health Organization (2019). The selection and use of essential medicines: report of the WHO Expert Committee on Selection and Use of Essential Medicines, 2019 (including the 21st WHO Model List of Essential Medicines and the 7th WHO Model List of Essential Medicines for Children). Geneva: World Health Organization. hdl:10665/330668. ISBN9789241210300. ISSN0512-3054. WHO technical report series;1021.
^Clinical trial number NCT03329092 for "A Study to Determine the Efficacy, Safety and Tolerability of Aztreonam-Avibactam (ATM-AVI) ± Metronidazole (MTZ) Versus Meropenem (MER) ± Colistin (COL) for the Treatment of Serious Infections Due to Gram Negative Bacteria. (REVISIT)" at ClinicalTrials.gov
^Clinical trial number NCT03580044 for "Efficacy, Safety, and Tolerability of ATM-AVI in the Treatment of Serious Infection Due to MBL-producing Gram-negative Bacteria" at ClinicalTrials.gov
^Kobayashi Y, Uchida H, Kawakami Y (December 1992). "Synergy with aztreonam and arbekacin or tobramycin against Pseudomonas aeruginosa isolated from blood". The Journal of Antimicrobial Chemotherapy. 30 (6): 871–2. doi:10.1093/jac/30.6.871. PMID1289363.