aztreonam, aztreonam lysine

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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.