What is cystic fibrosis (CF)?

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Cystic fibrosis is a genetic condition, which means that it is something you are born with. Cystic fibrosis is known to cause your lungs to produce extra-thick, sticky mucus. This mucus builds up and clogs your airways.

Even before symptoms present, people with cystic fibrosis develop mucus that is thicker and stickier than normal.

Affected lungs

Healthy lungs: The lungs naturally produce a thin layer of mucus that helps protect the airways from dangerous bacteria that can cause infections.

Lungs affected by CF: For people living with CF, the mucus in the lungs is thicker than normal. This thick mucus can build up in the airways, allowing germs to thrive and become a source of infection and inflammation. Inflammation is caused by your immune system’s response to something harmful, and inflammation can lead to decreased lung function.


Sticky mucus contributes to the progression of cystic fibrosis over time 

Controlling mucus early in the course of cystic fibrosis may be an important part of managing the disease.

Mucus cycle

When white blood cells fight an infection caught in the mucus, they leave behind remains of the infection. This is called extracellular DNA. The buildup of these remains makes the mucus in lungs affected by CF even thicker than before. This leaves your lungs even more vulnerable to decreased lung function. Because the mucus is even more thick and sticky, it is more difficult for the body to remove.

This may begin a cycle of blockage, infection, and inflammation that may lead to poorer lung function.


Signs and symptoms of pulmonary exacerbations, or flare-ups, from CF include:

  • Increased cough
  • Changes in mucus (volume or consistency)
  • Loss of appetite or weight
  • Worsening lung function

Living with Cystic Fibrosis

Get the most out of your treatment

  • Understanding treatments: Each treatment works differently to support you
  • Establish a routine: Building a routine can help you stay on track and stay healthy
  • Maintain a positive attitude: Managing CF can be a challenge, but keeping a positive attitude goes a long way to help you stay on track

Helpful tips on how to stay ahead of CF

Eating well, being active, and establishing treatment routines may help you manage your CF

  • Eating a high-calorie, high-fat diet is important to help make sure you are getting the nutrients you need from food
  • Exercise as often as you can to help manage lung function. The effect of Pulmozyme (dornase alfa) on exercise tolerance has not been established in adults or children
  • Partner with your CF Care Team to come up with a treatment routine that works best for you
  • Make time every day for your Pulmozyme (dornase alfa) and other cystic fibrosis treatments

It is important to discuss these plans with your doctor and your CF Care Team to find the right balance to fit your unique needs.

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Get info on our CF treatment support programs

Indication and Usage

Pulmozyme (dornase alfa) is indicated, along with standard therapies, for the management of pediatric and adult patients with cystic fibrosis (CF) to improve pulmonary function.

In CF patients with an FVC ≥ 40% of predicted, daily administration of Pulmozyme has also been shown to reduce the risk of respiratory tract infections requiring injectable antibiotics.

Pulmozyme should not be used in patients who are allergic to any of its ingredients.

Patients may experience the following when using Pulmozyme: change in or loss of their voice, discomfort in the throat, rash, chest pain, red watery eyes, runny nose, lowering of lung function, fever, indigestion, and shortness of breath. There have been no reports of severe allergic reactions caused by the administration of Pulmozyme. Mild to moderate hives and mild skin rash have been observed and have been short-lived.

Pediatric Use

The safety and effectiveness of Pulmozyme along with standard therapies for cystic fibrosis have been established in pediatric patients. The use of Pulmozyme in pediatric patients at 5 to 17 years of age is supported by evidence from a randomized, controlled trial. The use of Pulmozyme in patients less than 5 years of age is supported by the efficacy data from the same randomized, controlled trial and additional safety data in pediatric patients aged 3 months to less than 5 years who received Pulmozyme.

You are encouraged to report side effects to Genentech and the FDA. You may report side effects to the FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. You may also report side effects to Genentech at 1-888-835-2555.

For further information, please see the Pulmozyme full Prescribing Information. If you have questions, please discuss them with your CF Care Team.