Bronchiectasis is a lung condition where damaged airways cause frequent infections and daily mucus build-up. Some treatments, called mucoactive agents are thought to help patients expectorate mucus, but their effectiveness has not been clear.
A UK-wide multicentre study tested whether two of these mucoactive treatments (regular nebulised hypertonic saline, a concentrated salty solution, or carbocisteine, a medicine that thins mucus) reduced lung flare-ups.
Study design
- 288 adults with non-cystic fibrosis bronchiectasis and frequent flare-ups.
- Participants received either:
- Hypertonic saline
- Carbocisteine
- Both treatments
- Standard care alone
- All continued their usual bronchiectasis care.
- Main goal: to compare the number of lung flare-ups over one year between the above groups.
- They also looked at quality of life and safety.
Key findings
- Neither hypertonic saline nor carbocisteine significantly reduced flare-ups.
- Participants had about 0.8–1 flare-ups per year, no matter the treatment.
- Side effects were similar across all groups.
Takeaway
- These common mucus-thinning treatments are safe but do not significantly prevent flare-ups.
- Treatment with hypertonic saline and / or carbocisteine may still make patients feel better, and could prevent flare-ups in some patients with particular types of bronchiectasis.
- More research is needed to find effective ways to reduce bronchiectasis flare-ups.
Important note for patients
- This study does not mean you should stop any prescribed treatments, including 7% saline nebulisers.
- These treatments can still help manage symptoms and are safe to continue. Always talk to your doctor or specialist before making any changes.
You can read the full published findings here:
N Engl J Med. 2025 Sep 28. doi: 10.1056/NEJMoa2510095. Epub ahead of print.
[Posted November 2025]