What is the mechanism of action of Pulmozyme in treating cystic fibrosis?

• A. Breaks down extracellular DNA in pulmonary secretions
• B. Inhibits bacterial growth
• C. Neutralizes viruses
• D. Stimulates coughing

Answer: (A)

Pulmozyme works by enzymatically breaking down extracellular DNA in the thick mucus of cystic fibrosis. In CF airways, DNA from degenerating white blood cells (neutrophils) muddles the secretions and makes mucus very viscous. By cleaving this DNA, the solution lowers both viscosity and elasticity of the mucus, so cilia can move it more easily and secretions can be cleared from the lungs. It’s delivered as an inhaled nebulized treatment to act directly in the airways. It doesn’t act by inhibiting bacteria, neutralizing viruses, or directly triggering coughing; the benefit comes from making mucus easier to clear.