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This product is manufactured by Gilead Sciences using the ingredient aztreonam.

This product is taken via nebulizer.

Why is it prescribed?

Aztreonam is an inhaled antibiotic used to treat P. aeruginosa lung infections in people with Cystic Fibrosis

  • Use via nebulizer exactly as the directions advise.
  • An inhaled bronchodilator should be used prior to each dose of Cayston®. Short acting bronchodilators can be taken between 15 minutes and 4 hours and long acting bronchodilators can be taken between 30 minutes and 12 hours prior to each dose.
  • The medication vials should be stored in a refrigerator at 2 to 8°C (36 to 46°F), however, vials may be stored at room temperature (up to 25°C/77°F) for up to 28 days. Diluent ampules may be refrigerated or stored at room temperature (15 to 30°C/59 to 86°F).
  • Do not use if stored at room temperature for more than 28 days. Unused vials  stored at room temperature for more than 28 days should be discarded. Do not store back in the refrigerator.
  • Do not use beyond the expiration date stamped on the vial. Do not use diluent beyond the expiration date embossed on the ampule.
  • Use immediately after reconstitution. Do not reconstitute more than one dose at a time.
  • Do not use diluent or reconstituted product if it is cloudy or if there are particles in the solution.



See other products used in the treatment of •cystic fibrosis •

The recommended dosage for both adults and children 6 years of age and older is one single- use vial (75 mg) reconstituted with one ampule of saline taken 3 times a day by inhalation for a 28-day treatment course. Each of the 3 daily doses should be taken at least 4 hours apart (e.g. morning, after school or work and before bed). The dosage is the same for patients regardless of age or weight.

When aztreonam is inhaled, it enters the lungs and come in contact with the P. aeruginosa bacteria that are present. It binds to certain P. aeruginosa proteins and interferes with the development of the bacterial cell wall causing the cell wall to break and killing the bacteria. By decreasing the number of P. aeruginosa bacteria living in the lungs, lung infection is reduced and respiratory symptoms and lung function are improved.

The most common side effects are:

  • cough
  • nasal congestion
  • wheezing
  • sore throat
  • fever
  • chest discomfort
  • runny nose

Contact your doctor if:

  • you develop a rash - this could mean that you have an allergic reaction to aztreonam
  • you have difficulty breathing (bronchospasm) immediately after inhalation.  Bronchospasm is a potential side effect with inhalation therapies such as this.

Do not use aztreonam:

  • if you are allergic to aztreonam or any components of this medication

Use aztreonam with caution:

  • if you have kidney or liver disease

Drug Interactions:

  • No known interactions

Safety in Pregnancy: Studies in animals suggest low risk in pregnancy but no human data available.

Safety in Breastfeeding: Use is likely safe if breastfeeding.