People with bronchitis and emphysema could find their life transformed by a new medicine currently being researched.
The conditions are known collectively as chronic pulmonary obstructive disease (COPD).
COPD is on the rise throughout the world, killing 2.74m people each year and by 2020 it will be the fourth leading cause of death in the world.
It is also a leading cause of disability. Sufferers' lung capacity can be reduced to 40% of that of a healthy lung, making even the most basic physical activity extremely difficult.
The new drug tiotropium has been widely tested in four studies over a 12 month period involving more than 1,400 patients at centres in the US, Belgium and the Netherlands.
Patients found it significantly improved the quality of their lives, making breathing easier and reducing attacks and visits to hospital.
It also allowed some to enjoy physical activities which were once out of bounds.
The effects of the drug were found to be long-lasting. It was easy to administer, and had only minor side effects such as a dry mouth.
In the studies, some patients were given tiotropium, while others were received either a dummy treatment or a recognised treatment called ipratropium.
The researchers measured the volume of air patients could breathe out in one second after breathing in as much as possible. This is known as the FEV 1 measurement.
The performance of the patients who took tiotropium improved by 20% just three hours after taking the treatment. Even 24 hours later their performance was improved by 10-12%.
There was also a big reduction in their shortness of breath, a condition known technically as dyspnea.
In the American studies, tiotropium produced a clinically significant improvement in dyspnea in nearly half of all the patients who took it.
The European authors also found that one patient in nine in the tiotropium group had not experienced any attacks during the year.
The tiotropium patients experienced 20-25% less attacks while taking the medication, and the number of times they were hospitalised as a result was cut by up to 50%.
Even when they were hospitalised, their average stay was up to 50% shorter.
Dr Walter Vincken, of the Academic Hospital University of Brussels and main author of the Belgian-Netherlands arm of the study, said: "The effects that we have seen on exacerbations (attacks) and hospitalisations are even more impressive than the effects on lung function.
"For a COPD patient, an exacerbation leading to hospitalisation is always an ordeal, a setback, a nuisance. So our results speak very strongly in tiotropium's favour."
Dr John Harvey, chairman of communications with the British Thoracic Society, said the trial results for tiotropium appeared to be good.
He said: "It is potentially quite exciting and the trial results seem to be good.
"But we do have to be careful as trials can sometimes give better results than when drugs are used in general cases."
Dr Harvey, who is also a respiratory consultant at Southmead Hospital, said it remained to be seen whether tiotropium should have a use for all sufferers or targeted at those with moderate to severe symptoms.
"Further studies should be done to determine this," he added.
Dame Helena Shovelton, of the British Lung Foundation, said: "We are very hopeful about new developments and new treatments for people with COPD, but treatment with drugs is not the only way to alleviate problems of lung disease."
She said methods such as pulmonary rehabilitation could make an enormous difference to how someone copes with COPD and manages their breathlessness.
"But both the right drug and rehabilitation together can have the greatest impact," she said.
The research is published in the European Respiratory Journal.