A Cornish GP who has carried out a pilot study of a drugs-free asthma treatment says it could save the NHS millions of pounds.
Dr Manley said the saving on drugs in a year could amount to £268m
Dr Rupert Manley says the Buteyko Method, using controlled breathing, has led to an improvement in his patients.
Most of the patients at his surgery in St Ives said they had used fewer drugs as a result of the training.
Dr Manley said the money saved nationally on asthma drugs could amount to nearly £270m.
He said: "The cost saving for asthma treatment was just more than £2,000 in the first year after the course which was for 13 patients.
"Now if you translate that nationally - we spend more than £500m a year on asthma treatment - you'd be looking to save something of the order of £268m."
Simon Paddon and Nikkie Jewell teach the Buteyko method throughout Devon and Cornwall.
The technique is named after a Russian medical scientist. It involves a five-day training course, which can be followed up with refresher courses if necessary.
But Nikkie Jewell says a few minutes of breathing exercises each day is normally sufficient to keep symptoms in check.
She told BBC News it was about retraining patients' breathing.
"What we're doing is normalising respiration - it's nothing quirky.
"Once things are back to normal, the body starts to heal itself."
The National Asthma Campaign said a recent study into breathing techniques had shown the use of inhalers could be reduced for some people by up to 80%.
But Erica Evansat Asthma UK said it was important for people to continue treatments which had been prescribed by their doctors.