From the Guidelines
Aztreonam should be used with caution in patients with penicillin or cephalosporin allergies, and its administration may be considered without prior testing unless there is a history of ceftazidime allergy, as suggested by the 2022 practice parameter update 1.
Key Considerations
- Aztreonam is a monobactam antibiotic effective against aerobic gram-negative bacteria, including Pseudomonas aeruginosa, E. coli, and Klebsiella.
- It is especially valuable for patients with IgE-mediated penicillin or cephalosporin allergies due to its minimal cross-reactivity.
- The typical adult dosage ranges from 1 to 2 grams every 6-12 hours, depending on infection severity, with a maximum daily dose of 8 grams.
- Treatment duration is usually 5-14 days based on the infection type.
- Aztreonam is administered intravenously or by intramuscular injection, with IV being more common for serious infections.
Clinical Guidelines
- According to the Infectious Diseases Society of America and the American Thoracic Society, aztreonam may be used as an alternative to β-lactam antibiotics in patients with severe penicillin allergy 1.
- The 2016 clinical practice guidelines for hospital-acquired and ventilator-associated pneumonia recommend aztreonam as an option for initial empiric antibiotic therapy in certain cases 1.
Safety and Efficacy
- Aztreonam has been shown to be effective against aerobic gram-negative organisms, but it is not effective against gram-positive bacteria and anaerobes.
- Common side effects include injection site reactions, rash, and gastrointestinal disturbances.
- Dosage adjustments are necessary for patients with renal impairment, and liver function monitoring is recommended during extended treatment.
Recent Recommendations
- The 2022 practice parameter update suggests that aztreonam may be administered without prior testing in patients with a history of penicillin or cephalosporin allergy, unless there is a history of ceftazidime allergy 1.
- This update also notes that aztreonam has become a commonly used acute therapeutic drug for patients with penicillin or cephalosporin allergy histories, but it is not as effective against gram-negative bacteria as other beta-lactams and has increasing rates of resistance.
From the FDA Drug Label
To reduce the development of drug-resistant bacteria and maintain the effectiveness of AZACTAM (aztreonam for injection, USP) and other antibacterial drugs, AZACTAM should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria AZACTAM is indicated for the treatment of the following infections caused by susceptible Gram-negative microorganisms: Urinary Tract Infections (complicated and uncomplicated), including pyelonephritis and cystitis (initial and recurrent) caused by Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Enterobacter cloacae, Klebsiella oxytoca*, Citrobacter species*, and Serratia marcescens*. Lower Respiratory Tract Infections, including pneumonia and bronchitis caused by Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Haemophilus influenzae, Proteus mirabilis, Enterobacter species, and Serratia marcescens* Septicemia caused by Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus mirabilis*, Serratia marcescens*, and Enterobacter species Skin and Skin-Structure Infections, including those associated with postoperative wounds, ulcers, and burns, caused by Escherichia coli, Proteus mirabilis, Serratia marcescens, Enterobacter species, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Citrobacter species*. Intra-abdominal Infections, including peritonitis caused by Escherichia coli, Klebsiella species including K pneumoniae, Enterobacter species including E. cloacae*, Pseudomonas aeruginosa, Citrobacter species* including C. freundii*, and Serratia species* including S. marcescens*. Gynecologic Infections, including endometritis and pelvic cellulitis caused by Escherichia coli, Klebsiella pneumoniae*, Enterobacter species* including E. cloacae*, and Proteus mirabilis*
AZTREONAM USE: Aztreonam is used to treat various infections caused by susceptible Gram-negative microorganisms, including:
- Urinary Tract Infections
- Lower Respiratory Tract Infections
- Septicemia
- Skin and Skin-Structure Infections
- Intra-abdominal Infections
- Gynecologic Infections It should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria 2.
From the Research
Aztreonam Use
- Aztreonam is a monobactam antibiotic that is selectively active against Gram-negative aerobic bacteria and inactive against Gram-positive bacteria 3.
- It is effective against Enterobacteriaceae, Pseudomonas aeruginosa, and other Gram-negative bacteria, but has minimal effect on indigenous faecal anaerobes 3, 4.
- Aztreonam must be administered intravenously or intramuscularly, as its absolute bioavailability is very low after oral administration 3.
- The elimination half-life of aztreonam is less than 2 hours, requiring 6- or 8-hourly administration for moderately severe or severe infections 3.
Clinical Uses
- Aztreonam has been shown to be effective in treating various Gram-negative infections, including:
- Aztreonam can be used as a single agent for treating susceptible aerobic Gram-negative pathogens, but combination therapy is recommended for mixed infections or those of unknown etiology 4, 5.