This medication is used to treat people with a certain inherited condition (cystic fibrosis) who have an ongoing lung infection with a certain bacteria (Pseudomonas aeruginosa). People with cystic fibrosis produce thick, sticky mucus that can plug up the tubes, ducts and passageways in the lungs. This can result in serious breathing problems and infections in the lungs.

Aztreonam belongs to a class of drugs known as beta-lactams. Aztreonam inhalation solution works by stopping the growth of a certain bacteria (Pseudomonas aeruginosa) that commonly infects the lungs of people with cystic fibrosis. This effect decreases lung infections and damage, decreases the use of other antibiotics, and helps to improve breathing.

This antibiotic treats only bacterial infections. It will not work for viral infections (such as the common cold, flu). Using any antibiotic when it is not needed can cause it to not work for future infections.

Read the Patient Information Leaflet and Instructions for Use provided by your pharmacist before you start using this medication and each time you get a refill. This medication is used with a special machine called a nebulizer that changes the solution to a fine mist that you inhale. Learn and follow all instructions for the use of this medication and the nebulizer. Children may need help from an adult to use this medication properly. If you have any questions, ask your doctor, pharmacist, or respiratory therapist.

Before treatment with inhaled aztreonam, you should inhale a bronchodilator (such as albuterol, formoterol, salmeterol). Ask your pharmacist or doctor how soon to pre-treat with the specific bronchodilator you are using.

Use this medication with the nebulizer as directed by your doctor, usually three times a day (every 8 hours). Each treatment lasts about 2 to 3 minutes. Do not swallow or inject this medication. This medicine is usually used for 28 days in a row, followed by 28 days without this medication, repeating the cycle until your doctor directs you to stop.

Each vial of aztreonam is for one-time use. Inspect each vial before use. Discard the vial if the prepared solution is cloudy or has particles in it, or if it has expired or has been stored at room temperature for longer than 28 days. Use all of the contents of the vial for each dose immediately after mixing the medication. Do not mix aztreonam with any other medicines in the nebulizer.

Do not use other forms of aztreonam in the nebulizer. Other forms of aztreonam may contain arginine which can cause breathing problems if inhaled.

For the best effect, use this antibiotic at evenly spaced times. To help you remember, use this medication at the same time(s) every day.

Continue to take this medication until the full prescribed amount is finished, even if symptoms disappear after a few days. Stopping the medication too early may result in a return of the infection.

Tell your doctor if your condition does not get better or if it gets worse.

Cough, chest discomfort, or headache may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including:

• wheezing

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

• rash
• itching/swelling (especially of the face/tongue/throat)
• severe dizziness
• trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before using aztreonam inhalation solution, tell your doctor or pharmacist if you are allergic to it; or to penicillins, cephalosporins, or certain other antibiotics (such as imipenem, meropenem); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

• kidney problems

Aztreonam may cause live bacterial vaccines (such as typhoid vaccine) to not work well. Tell your health care professional that you are using aztreonam before having any immunizations/vaccinations.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

It is unknown if inhaled aztreonam passes into breast milk. However, other forms of this drug pass into breast milk in very small amounts, and many doctors consider breastfeeding safe while using this drug. Consult your doctor before breastfeeding.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Some of the products that may interact with this drug include:

• cefoxitin
• imipenem

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669.

Do not share this medication with others.

Lab and/or medical tests (such as breathing tests, bacterial cultures) may be done while you are using this medication. Keep all medical and lab appointments. Consult your doctor for more details.

It is important not to miss any doses. If you miss a dose, you can still use all 3 daily doses as long as you leave at least 4 hours between each dose. Do not double the dose to catch up.

Store in the refrigerator away from light. This medication may also be stored at room temperature if needed. If the medication is stored at room temperature, discard after 28 days. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired, or no longer needed, or if it has been stored at room temperature for more than 28 days. Consult your pharmacist or local waste disposal company.