inhalation

Question

Hi, I use ACC for inhalation, but I have heartburn and stomach difficulties, so I wish to ask you for advice. What is the difference between dornase and acetylcystein? Do you think that I can start dornase? Thank you.

Answer

Dear questioner,
it is a question whether your problems are caused by acetylystein. In the instruction leaflet nausea and vomiting is described as a less common side effect of ACC, heartburn is not mentioned.

You asked about the difference between ACC and dornase. From both drugs one expects an improved clearance of secretions due to a reduced viscosity of the mucus. The mechanism by which this is achieved is however different for both drugs. ACC cleaves so-called di-sulfide bridges of large molecules called "mucopolysaccharides" which are responsible for the viscosity of the mucus in the bronchial system. Dornase is an enzyme which selectively cleaves deoxyribonucleic acid (DNA), the genetic material of degenerated leukocytes present in CF sputum. Excess of DNA increases the viscosity of sputum. Dornase hydrolyzes the DNA and so reduces the viscosity.

The available data about the two drugs which is summerized in the American
Cystic Fibrosis Pulmonary Guidelines (Flume et al. 2007 Am J Respir Crit
Care Med 176:957-969: Cystic Fibrosis Pulmonary guidelines) points out the benefit of dornase alpha inhalation for CF patients with moderate to severe lung disease and even for asymptomatic or mild courses. The available data on ACC is not so exuberant to make a clear statement.
It is only your CF doctor who can give you an advice; he is also the only one who can prescribe dornase for you. I suppose that you are from Slovakia, where 3 CF centres are in function, therefore it is necessary to ask them. Good luck.
Vera Vavrova

04.01.2009