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Related to aztreonam: gentamicin


a narrow-range antibiotic effective against aerobic gram-negative bacteria; used for the treatment of infections caused by susceptible organisms. Administered intravenously or intramuscularly.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

aztreonam, aztreonam lysine

Azactam, Cayston

Pharmacologic class: Monobactam

Therapeutic class: Anti-infective

Pregnancy risk category B


Inhibits bacterial cell-wall synthesis during active multiplication by binding with penicillin-binding protein 3, resulting in cell-wall destruction


Inhalation solution: 75-mg single-use vial

Powder for injection: 500-mg vial, 1-g vial, 2-g vial, 1 g/50-ml I.V. bag, 2 g/50-ml I.V. bag

Indications and dosages

Cystic fibrosis in patients with Pseudomonas aeruginosa

Adults and children age 7 and older: 75 mg t.i.d. at least 4 hours apart for 28-day course, followed by 28 days off

Infections caused by susceptible gram-negative organisms

Adults: For urinary tract infections, 500 mg or 1 g I.M. or I.V. q 8 or 12 hours; for moderately severe systemic infections, 1 or 2 g I.M. or I.V. q 8 or 12 hours; for severe or life-threatening infections, 2 g I.M. or I.V. q 6 or 8 hours. Maximum dosage is 8 g/day.

Children: For mild to moderate infections, 30 mg/kg I.M. or I.V. q 8 hours; for moderate to severe infections, 30 mg/kg I.M. or I.V. q 6 or 8 hours. Maximum dosage is 120 mg/kg/day.

Dosage adjustment

• Severe renal failure


• Hypersensitivity to drug or its components


Use cautiously in:

• renal or hepatic impairment

• elderly patients

• pregnant or breastfeeding patients.


• Flush I.V. tubing with compatible solution before and after giving drug.

• Compatible solutions include 0.9% sodium chloride injection, 5% or 10% dextrose injection, Ringer's or lactated Ringer's injection, 5% dextrose and 0.9% sodium chloride injection, and 5% dextrose and 0.45% sodium chloride injection.

• After adding diluent to vial or infusion bottle, shake immediately and vigorously.

• For I.V. bolus injection, reconstitute powder for injection by adding 6 to 10 ml of sterile water for injection. Inject prescribed dosage into tubing of compatible I.V. solution slowly over 3 to 5 minutes.

• For intermittent I.V. infusion, reconstitute powder for injection by adding compatible I.V. solution to yield a concentration not exceeding 20 mg/ml. Administer prescribed dosage over 20 to 60 minutes.

Thaw commercially available frozen drug at room temperature and give by intermittent I.V. infusion only.

• For I.M. injection, reconstitute powder for injection by adding 3 ml of sterile water for injection or 0.9% sodium chloride injection.

• Give I.M. injection deep into large muscle mass.

• Reconstitute inhalation solution with 1 ml sterile diluent supplied and administer only with nebulizer supplied. Don't reconstitute until ready to administer.

• Know that patient should use a bronchodilator as prescribed before using inhalation solution.

Adverse reactions

CNS: dizziness, confusion, seizures

CV: phlebitis, thrombophlebitis

EENT: diplopia, tinnitus

GI: nausea, vomiting, diarrhea (including diarrhea associated with Clostridium difficile), pseudomembranous colitis

Hematologic: neutropenia, pancytopenia

Hepatic: hepatitis

Respiratory: bronchospasm

Skin: rash, toxic epidermal necrolysis

Other: altered taste, angioedema, anaphylaxis


Drug-drug. Aminoglycosides: increased risk of nephrotoxicity and ototoxicity

Beta-lactamase-inducing antibiotics (such as cefoxitin, imipenem): antagonism with aztreonam

Furosemide, probenecid: increased aztreonam levels

Drug-diagnostic tests. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine, eosinophils, platelets, prothrombin time (PT), partial thromboplastin time (PTT): increased values

Coombs' test: positive result

Neutrophils: decreased count

Patient monitoring

Assess patient closely for signs and symptoms of pseudomembranous colitis.

Monitor patient carefully for hypersensitivity reaction, especially if he's allergic to penicillin, carbapenems, or cephalosporins.

• Monitor CBC with differential, AST, ALT, PT, PTT, and serum creatinine values.

• Monitor renal and hepatic function.

Patient teaching

• Show patient how to reconstitute inhalation solution using diluent supplied and tell patient not to reconstitute until ready to use. Advise patient to use only the nebulizer supplied and to use a bronchodilator as prescribed before using inhalation solution.

Instruct patient to immediately report severe diarrhea or signs or symptoms of hypersensitivity reaction, such as rash or difficulty breathing.

• Tell female patient to notify prescriber if she is pregnant or breastfeeding.

• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the tests mentioned above.


McGraw-Hill Nurse's Drug Handbook, 7th Ed. Copyright © 2013 by The McGraw-Hill Companies, Inc. All rights reserved


A synthetic antibiotic, C13H17N5O8S2, that acts against a wide spectrum of gram-negative bacteria.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


A BETA-LACTAM antibiotic effective against aerobic GRAM NEGATIVE organisms. A brand name is Azactam.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005
References in periodicals archive ?
The TARGET study1 was a randomized, double-blind, multicenter, phase 3 study, which enrolled 679 patients with ABSSSI and compared the safety and efficacy of ceftobiprole medocaril (equivalent to ceftobiprole 500 mg) given intravenously three times daily with intravenous vancomycin 1000 mg (or 15 mg/kg) given twice-daily plus intravenous aztreonam 1000 mg given twice-daily.
The MBL enzymes are able to destroy [beta]-lactams and are associated with emerging resistance to all [beta]-lactams including penicillins, carbapenems, extended-spectrum cephalosporins, but not aztreonam. (6) Also, VIM and IPM are the most important MBL variants.
pneumoniae, the rates of resistance were counted 71.8% for trimethoprim/sulfamethoxazole 71.4% for cefuroxime and cefotaxime; 67.3% for cefepime, 65.2% for aztreonam and 64.2% for piperacillin.
Other than that, for all other antibiotics such as piperacillin-tazobactam, cefotaxime, ceftazidime, tetracycline, cotrimoxazole, aztreonam, and gentamicin isolates showed complete resistance 20/20 (100%) [Table 2].
Resistance by disk diffusion technique noted in Salmonella Paratyphi A was ampicillin 60%, chloramphenicol 40%, cotrimoxazole 38%, ceftriaxone 7.9%, ciprofloxacin 8%, cefpodoxime 7.9%, imipenem and ertapenem 2.6%, aztreonam 1.3%, moxifloxacin 6.6%, and gatifloxacin 1.3%.
The following antibiotic discs were tested: ceftazidime (30 [micro]g), cefepime (30 [micro]g), piperacillin-tazobactam (100 [micro]g/10 [micro]g), Imipenem (10 [micro]g), Meropenem (10 [micro]g), Gentamicin (10 [micro]g), Amikacin (30 [micro]g), Ampicillin-sulbactam (10 [micro]g/10 [micro]g), Cotrimoxazole (25 [micro]g), aztreonam (30 [micro]g), Ciprofloxacin (5 [micro]g), Norfloxacin (30 [micro]g) (for urinary isolates), Polymyxin B (300 units), and Colistin (10 [micro]g).
ESBL production of the isolate was screened according to CLSI breakpoints for cefpodoxime, ceftazidime, aztreonam, cefotaxime, and ceftriaxone.
The different anti-microbials tested were piperacillin (100 ug), ceftazidime (30 ug), amikacin (30 ug), piperacillin-tazobactam (100/10 ug), imipenem (10 ug), ciprofloxacin (5 ug), cefepime (30 ug), ceftriaxone (30 ug), aztreonam (30 ug) and cefoperazone (30 ug).
The antibiotics investigated in the study included penicillins (ampicillin, carbenicillin and piperacillin), 1st generation cephalosporins (cephalothin), 2nd generation cephalosporins (cefuroxime, cefoxitin and cefaclor), 3rd generation cephalosporins (ceftriaxone, cefotaxime and ceftazidime), 4th generation cephalosporins (cefepime) carbapenems (imipenem) and monocyclic lactams (aztreonam).
The hospital's EHR system generated a daily list of patients with a history of penicillin allergy who were on second-line options--vancomycin, daptomycin, aztreonam, linezolid, or moxifloxacin--for infections that would be better treated with beta-lactam antibiotics.
Cinco aislamientos fueron resistentes a todos los antibioticos ensayados excepto a Colistina; solo un aislado de K pneumoniae fue sensible ademas a gentamicina y otro al aztreonam. Esto difiere de los resultados obtenidos en Colombia, donde todos los aislamientos fueron resistentes a los [beta]-lactamicos excepto aztreonam, resistentes a gentamicina, amikacina y trimetoprim-sulfametoxazole pero susceptibles a ciprofloxacina, tetracicilina, tigeciclina y colistin (3).