Dornase Alfa

INTRODUCTION

Indications

Adjunct management (with standard therapy) of cystic fibrosis.

Action

Breaks down excessive amounts of DNA found in the respiratory tract of patients with cystic fibrosis. Excessive DNA contributes to increased sputum viscosity and risk of infection. Therapeutic Effects: Decreased infection rates and requirement for parenteral anti-infectives. Improved pulmonary function.

Adverse Reactions/Side Effects

EENT: sore throat, voice alteration, conjunctivitis, hoarseness, rhinitis. Resp: cough, dyspnea. CV: chest pain. Derm: rash. Misc: fever.

PHYSICAL THERAPY IMPLICATIONS

Examination and Evaluation

• Assess the quantity and consistency of sputum to help document whether this drug is successful in reducing the viscosity of respiratory secretions.

• Monitor any chest pain and attempt to determine if pain is drug-induced or caused by cardiovascular dysfunction (e.g., angina that occurs during exercise).

• Assess any breathing problems, and report severe or persistent cough or difficult, labored breathing.

Interventions

• When implementing airway clearance techniques or other pulmonary interventions, attempt to intervene when the drug has produced mucolytic effects. Effects typically begin 15 min after inhalation.

• Design and implement breathing exercises to maximize ventilation and help prevent infections caused by pulmonary congestion.

Patient/Client-Related Instruction

• Counsel patient and family/caregivers on proper inhalation techniques. Emphasize the need to adhere to the recommended dose and frequency of inhalations.

• Instruct patient and family/caregivers to report other troublesome side effects such as severe or prolonged headache, skin rash, fever, nasal inflammation, eye irritation, sore throat, hoarseness, or voice changes.

Pharmacokinetics

Absorption: Negligible absorption following inhalation.

Distribution: Action is primarily local.

Metabolism and Excretion: Unknown.

Half-life: Unknown.

Contraindications/Precautions

Contraindicated in: Hypersensitivity to dornase alfa or Chinese Hamster Ovary cell products.

Use Cautiously in: Children (incidence of cough, rhinitis, and rash is increased); Pregnancy or lactation (safety not established).

Interactions

Drug-Drug: None significant.

Route/Dosage

Inhaln (Adults and Children): 2.5 mg 1–2 times daily.

Availability

Solution for inhalation: 1 mg/mL in 2.5-mL single-use ampules.