Dornase Alfa (Recombinant Human Deoxyribonuclease; DNase)

 Action Cleaves DNA released by neutrophils that are mobilized to respiratory tract in response to infection, reducing viscoelasticity of purulent lung secretions, increasing airflow and decreasing risk of infection.

 Indications Treatment of cystic fibrosis.

 Contraindications Hypersensitivity to Chinese hamster ovary cell products.

 Route/Dosage

ADULTS & CHILDREN > 5 YR: Inhalation 2.5 mg once daily by oral inhalation via nebulizer; patients > 21 yr and those with baseline forced vital capacity > 85% benefit from 2.5 mg bid.

 Interactions

None well documented.

 Lab Test Interferences None well documented.

 Adverse Reactions

CV: Chest pain. DERM: Rash. EENT: Conjunctivitis; sore throat; voice alterations; hoarseness. RESP Hoarseness; pharyngitis; laryngitis.

 Precautions

Pregnancy: Category B. Lactation: Undetermined. Children: Safety and efficacy in children < 5 yr not established.

 Administration/Storage

• Use in conjunction with standard therapies for cystic fibrosis.
• Discard solution if cloudy or discolored.
• Discard unused portions of ampules.
• Do not dilute or mix drug with other drugs in nebulizer.
• Keep refrigerated and protected from strong light. Storing at room temperature for < 24 hr does not adversely affect product.

 Assessment/Interventions

• Obtain patient history, including drug history and any known allergies.
• Assess patient's ability to clear secretions. Provide assistance with coughing, positioning (semi-Fowler's or sitting upright) and suctioning.
• Provide hydration to liquefy secretions and replace fluids.
• Perform auscultation to determine quality of breath sounds. Note characteristics of cough and sputum.
• Perform chest physiotherapy (percussion and postural drainage) as ordered.

 Patient/Family Education

• Teach patient to follow manufacturer's instructions on use and maintenance of nebulizer and compression system.
• Instruct patient in proper administration and storage of drug.
• Tell patient that drug may cause sore throat, voice alterations or hoarseness and to inform physician if these or any other symptoms become bothersome.
• Inform patient that benefits of treatment may not become apparent for months.
• Emphasize importance of avoiding contraction of respiratory infections.