Up to 1.3 million adult asthma patients in the UK may be wrongly diagnosed with the condition and taking medicines they don’t need, according to the National Institute for Health and Care Excellence.

Publishing the first ever draft guideline to improve asthma diagnosis, the NHS cost watchdog said while 4.1 million people receive treatment in the UK evidence suggests that up to 30% do not have clear evidence of the condition. 

“Some may have had asthma in the past, but it is likely that many have been given an incorrect diagnosis,” the Institute said.

Its guidelines, which are now out for consultation, recommend spirometry as the first-line investigation for asthma in adults older than 16 and children aged five-16 years. 

Asthma UK has welcomed the development of the guideline, but notes that the claim 1.2 million might be getting the wrong treatment is based on small scale studies. 

“It is vital that no one with an asthma diagnosis stops taking their medication on the basis of this information, without discussions with their doctor,” the charity stressed.