Types of Mucus Thinners Used to Treat Cystic Fibrosis

Reviewed by: HU Medical Review Board | Last reviewed: May 2022 | Last updated: September 2022

Just as the name implies, mucus thinner (mucolytics) help thin the thick, sticky mucus that clogs the airways of people with cystic fibrosis (CF). Mucus thinners are inhaled either before or during airway clearance techniques because they assist with moving the mucus out of the lungs. Getting extra mucus out of the airways helps prevent infections and slows damage to the lungs.

Types of mucolytics for cystic fibrosis

The most common types of mucolytics prescribed for people with cystic fibrosis are:

  • Hypertonic saline
  • Dornase alfa (Pulmozyme®)
  • Mannitol (Bronchitol)
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The CF Foundation recommends that mucus thinners be used after a bronchodilator and before airway clearance techniques. An inhaled antibiotic follows at the end so that the infection-fighting drugs get deeper into the lungs.1 After use, all equipment must be cleaned and disinfected to prevent the spread of germs.

What is hypertonic saline?

Hypertonic saline, a sterile saline solution (salty liquid), comes in concentrations of 3% or 7%. It helps thin mucus by increasing the amount of salt in the airways. This salt attracts water to the mucus, thinning it and making it easier to cough out. Research shows that using hypertonic saline twice a day reduces the number of lung infections in people with CF.2

How is hypertonic saline administered?

Hypertonic saline is most often inhaled as a mist through a nebulizer or compressor. It does not remain in the system, so its benefits are temporary. Hypertonic saline should not be taken at the same time as other medications.

Because it is salty, hypertonic saline can damage computers and other electronic equipment. Therefore, it should not be used too close to electronics.

What are side effects of hypertonic saline?

Common side effects of hypertonic saline include:

  • Increased cough
  • Sore throat
  • Tightness in the chest3

These are not all the possible side effects of hypertonic saline. Talk to your doctor about what to expect or if you experience any changes that concern you during treatment with hypertonic saline.

What is dornase alfa?

Dornase alfa (Pulmozyme®) also helps thin mucus when inhaled. This drug acts like scissors cutting up the long DNA strands in white blood cells. Cutting the strands into shorter bits helps break up the thick, sticky mucus of CF.

How is dornase alfa administered?

The CF Foundation recommends dornase alfa, or DNase, for people with CF who are age 6 and older to improve lung function and reduce exacerbations.3 Dornase alfa should be refrigerated until it is used. The drug is delivered to the lungs through a nebulizer. The prescription often must be filled at a specialty pharmacy.

What are side effects of dornase alfa?

Common side effects of dornase alfa include:3

  • Change or loss of voice
  • Throat discomfort
  • Red, watery eyes
  • Rash
  • Dizziness
  • Fever
  • Runny nose

These are not all the possible side effects of dornase alfa. Talk to your doctor about what to expect or if you experience any changes that concern you during treatment with dornase alfa.

What is mannitol (Bronchitol)?

Mannitol is an inhaled powder for people who are age 18 and older that makes it easier to cough up mucus, although is unknown how it works. Before being prescribed, your CF care team will have you use mannitol as a test, and determine if right for you.

Mannitol does not remain in your system, unlike medications such as antibiotics, so the thinned mucus benefits are temporary. So, it is important to directly follow mannitol with airway clearance techniques, or dornase alfa if you take it. Your mucus is still thin at this time and will be easier to move out of your airways.

How is mannitol administered?

Mannitol is taken twice a day, once in the morning and once in the evening (about 2 to 3 hours before bedtime).

Mannitol comes with a handheld inhaler and tablets (typically 10 in a blister pack).

What are the side effects of mannitol?

Common side effects of mannitol include:

  • Cough
  • Coughing up blood
  • Pain or irritation in the back of your mouth and throat and discomfort when swallowing
  • Vomiting
  • Fever
  • Joint pain
  • Bacteria in your sputum

These are not all the possible side effects of mannitol. Talk to your doctor about what to expect or if you experience any changes that concern you during treatment with mannitol.

If your insurance plan will not cover the cost of hypertonic saline, dornase alfa, or mannitol, contact the CF Foundation’s Compass service for help at:

Phone: 1-844-COMPASS (1-844-266-7277)
Email: compass@cff.org
Monday - Friday, 9 a.m. - 7 p.m. ET

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