[MargaretR]

I have been suffering from 'breathlessness on exertion' for a year now.
Doc did ECG and blood tests and said they were all 'normal'.

A chest xray showed early signs of COPD(emphysema) but not bad enough to warrant medication.
He supplied an inhaler anyway saying he was bending the rules, and it would 'halt progress of COPD'.
My websearching found a medical study done in India where that inhaler increased risk of heart disease and stroke by 40%.
So that got binned sharpish
(I am in better nick than Amy Winehouse - who isn't?)

When considering whether a blood test result is 'normal', the Nhs is often years behind the latest research.
My serum B12 level is normal by our Nhs standards but would be considered dangerous by the Japanese and in several other countries.
I began a regime of food supplements with special reliance on vitamin B12.
My breathlessness has reduced by 50% in a few months, and I 'move faster' and the improvement continues.

So I can say from personal experience that breathlessness is not caused solely by lung disease.

I now take no prescription drugs whatsoever - not even paracetemol - Zantak(Ranitidine) contributed to my B12 deficiency - that got binned too
Anything that doesn't involve drugs I would try - looks like that machine is ideal if I get bad enough to need it.