n-acetylcysteine, an Antioxidant, Reduces Exacerbations of COPD

Benefits of n-acetylcysteine in Reducing COPD Exacerbation

Background: An exacerbation means sudden worsening of cough and/or shortness of breath usually due to a chest infection. It can have a major impact on someone’s daily life and may be bad enough to require a visit to the doctor or Emergency Department. So, prevention of an exacerbation for someone with COPD is an important goal in the management. Study: In this study of 120 patients performed in Hong Kong, China, the authors (Tse and colleagues) tested whether n-acetylcysteine (abbreviated NAC) might prevent exacerbations in two groups of patients with COPD: low risk – less than two exacerbations in the previous year; and high risk – 2 or more exacerbations in the previous year. Half of the patients took 600 mg of NAC twice a day, and the other half took identical placebo tablets twice a day. Neither the patients nor the doctors knew who was taking which medication for the one year period. Results were published in the September 2014 issue of CHEST (volume 146; pages 611 – 623). Results: NAC was successful in reducing the number of exacerbations and in prolonging the time until the first exacerbation occurred only in the high risk patients (2 or more exacerbations in the previous year), but not in the low risk patients. There were no major side effects with NAC or placebo. How does NAC work? NAC is an antioxidant that fights inflammation and thins mucus in the breathing tubes. What do these results mean for you? You should remember that there are many things that you can do to prevent getting sick and having an exacerbation. These include: 1. get flu and pneumonia vaccines 2. avoid inhaling cigarette smoke and airborne irritants 3. use good hand hygiene by not touching your eyes, nose, and mouth with your fingers 4. stay physically active as participation in pulmonary rehabilitation reduces exacerbations 5. ask your doctor about medications approved by the Food and Drug Administration to reduce a COPD exacerbation. These include salmeterol and fluticasone propionate (Brand name: Advair); tiotropium (Brand name: Spiriva); vilanterol and fluticasone furoate (Brand name: Breo); and roflumilast (Brand name: Daliresp) If you had 2 or more exacerbations in the previous 12 months, you are considered at high risk for having another one. I suggest that you discuss the results of this study with your health care professional to find out if he or she believes that NAC may be helpful for you. NAC does not require a prescription, and is typically available at a health food store or can be ordered on line.
One product of n-acetylcysteine

One product of n-acetylcysteine

If you take NAC, I strongly recommend the 600 mg dose twice daily as used in this study published in CHEST. You should expect that it will take several months or longer to find out if it will be helpful. However, NAC offers one more option to help prevent a COPD exacerbation.

Donald A. Mahler, M.D. is Emeritus Professor of Medicine at Geisel School of Medicine at Dartmouth in Hanover, New Hampshire. He works as a pulmonary physician at Valley Regional Hospital in Claremont, NH, where he is Director of Respiratory Services.