Dosing and uses of Cayston (aztreonam inhalation)
Adult dosage forms and strengths
inhalation solution
- 75mg/single-use vial
Cystic Fibrosis (CF)
Indicated to improve respiratory symptoms in patients with CF infected with Pseudomonas aeruginosa
75 mg inhaled q8hr for 28 days; use only with Alterna nebulizer
Doses should be administered at least 4 h apart
Use bronchodilator before administration; administer short-acting beta agonists 15 min to 4 h before or long-acting beta agonists 30 min to 12 h before
If taking mucolytics, take after bronchodilators, but before aztreonam
Other Information
Store vials and diluent refrigerated at 2-8 degrees C (36-46 degrees F)
Once removed from refrigerator, may store at room temperature (up to 25 degree C; 77 degrees F) for up to 28 days
Use immediately upon reconstitution; do not reconstitute more than 1 dose at a time
Pediatric dosage forms and strengths
inhalation solution
- 75mg/single-use vial
Cystic Fibrosis (CF)
Indicated to improve respiratory symptoms in patients with CF infected with Pseudomonas aeruginosa
<7 years: Safety/efficacy not established
7 years or older: As adults, 75 mg inhaled q8hr for 28 days; use only with Alterna nebulizer
Doses should be administered at least 4 h apart
Use bronchodilator before administration; administer short-acting beta agonists 15 min to 4 h before or long-acting beta agonists 30 min to 12 h before
If taking mucolytics, take after bronchodilators, but before aztreonam
Other Information
Store vials and diluent refrigerated at 2-8 degrees C (36-46 degrees F)
Once removed from refrigerator, may store at room temperature (up to 25 degree C; 77 degrees F) for up to 28 days
Use immediately upon reconstitution; do not reconstitute more than 1 dose at a time
Cayston (aztreonam inhalation) adverse (side) effects
>25%
Cough (54%)
10-25%
Nasal congestion ( 16%)
Wheezing (16%)
Pharyngolaryngeal pain (12%)
Pyrexia (13%)
1-10%
Chest discomfort (8%)
Abdominal pain (7%)
Vomiting (6%)
Bronchospasm (3%)
Rash (2%)
Warnings
Contraindications
Hypersensitivity
Cautions
Allergic reactions observed in clinical trials, stop treatment if allergic reaction occurs
May cause bronchospasm, stop treatment if chest tightness develops during nebulizer use
Increases FEV1 during 28-day course, consider baseline FEV1 when evaluating whether post-treatment changes in FEV1 are caused by pulmonary exacerbation
Increased risk of drug-resistant bacteria in absence of known Pseudomonas aeruginosa
Pregnancy and lactation
Pregnancy category: B
Lactation: Excreted in human milk at concentrations <1% of those determined in simultaneously obtained maternal serum; breastfeeding unlikely to pose risk
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Cayston (aztreonam inhalation)
Mechanism of action
Inhibits cell wall synthesis by binding to penicillin binding protein 3; member of monobactam family
Pharmacokinetics
Half-Life: 2.1 hr
Absorption: Low systemic absorption
Mean Plasma Concentration: 0.59 mcg/mL (1 hr after single dose, approximately the peak plasma conc); 0.55 mcg/mL, 0.67 mcg/mL, 0.65 mcg/mL (1 hr after multiple doses on days 1, 14, and 28 respectively); in contrast, plasma concentration following 500 mg IV is 54 mcg/mL
Mean Sputum Concentration: 726 mcg/g (after single dose); 984 mcg/g, 793 mcg/g, 715 mcg/g (10 min after multiple doses on days 1, 14, and 28 respectively)
Peak Plasma Time: Approximately 1 hr
Protein Bound: 56%
Excretion: Urine (60-70%); feces (13-15%)
