How does this medication work? What will it do for me?

Dornase alfa is a medication that is used in combination with other medications to treat cystic fibrosis. It is used to reduce the risk of respiratory tract infections (e.g., bronchitis, pneumonia) and to improve lung function. It works by breaking up DNA (genetic material) in sputum, making it less thick and easier to clear from the lungs.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. As well, some forms of this medication may not be used for all of the conditions discussed here. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

What form(s) does this medication come in?

Each ampule of sterile, clear, colourless, aqueous solution contains dornase alfa 1 mg/mL (2.5 mg). Nonmedicinal ingredients: calcium chloride dihydrate, sodium chloride, and sterile water for injection. This medication does not contain any preservatives.

How should I use this medication?

The usual dose of this medication is one 2.5 mg ampule inhaled once a day using the recommended nebulizer. Some people may use this medication twice a day if recommended by their doctor.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

It is important to use this medication exactly as prescribed by your doctor and that you understand how to use and maintain the nebulizer. Read the patient instructions provided and talk to your doctor or pharmacist if you are not sure how to use this medication properly. Use the nebulizer and mouthpiece that is recommended or provided to you. Do not mix this medication with any other medication in the nebulizer. Before using an ampule, squeeze it to ensure it does not leak. This medication contains no preservative and once an ampule is opened, the entire content must be used or discarded.

If you miss a dose, use it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication in the refrigerator, protect it from light, and keep it out of the reach of children.

This medication should be kept refrigerated during travelling and should not be at room temperature for more than 24 hours. If you notice that the solution is cloudy or discoloured, do not use it and discard it.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Who should NOT take this medication?

Do not use this medication if you:

  • are allergic to dornase alfa or any ingredients of this medication
  • are allergic to Chinese hamster ovary cell products

What side effects are possible with this medication?

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

  • chest pain
  • cough
  • difficulty breathing
  • fever
  • heartburn
  • laryngitis
  • rash
  • red eyes or swelling of the eyelids
  • runny nose
  • sore throat
  • voice changes

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.

Stop taking the medication and seek immediate medical attention if any of the following occur:

  • signs of a severe allergic reaction (e.g., hives; difficulty breathing; swelling of the face, mouth, tongue, or throat)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Are there any other precautions or warnings for this medication?

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while using this medication, contact your doctor.

Breast-feeding: It is not known if dornase alfa passes into breast milk. If you are a breast-feeding mother and are using this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for children less than 5 years old.

What other drugs could interact with this medication?

Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications that you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them. Depending on your specific circumstances, your doctor may want you to:

  • stop taking one of the medications,
  • change one of the medications to another,
  • change how you are taking one or both of the medications, or
  • leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. In many cases, interactions are intended or are managed by close monitoring. Speak to your doctor about how any drug interactions are being managed or should be managed.