More and more of the 3.4 million people with asthma in the UK are turning to alternative treatments, and there is evidence that techniques such as acupuncture and yoga have a positive impact.

Yet research by the National Asthma Campaign shows that more than a third of GPs will not recommend complementary medicine to their patients, mainly because there is little scientific evidence that it works.

A report entitled The Jury's Out, published by the charity, calls for for the barriers between the two areas of medicine to come down to ensure complementary therapies are appropriately used.

It also calls for more research into the safety, efficacy and cost-effectiveness of alternative therapies. It is crucial to know, the NAC says, whether such therapies work simply by relaxing people, or whether they actually result in a physical change to the symptoms of asthma.

The NAC also wants better training and regulation for people who practice alternative therapies.

'Suspicion and territorialism'

Anne Bradley, the charity's chief executive, said: "Suspicion and territorialism benefit no one - least of all the people who are ill.

"Regardless of whether complementary medicine works, we know from our own and other surveys that people with asthma are using complementary medicine so we simply can't ignore it, and need to address some of the problems as best we can now.