I posted a while ago on this topic and I thought I would update as it might be useful for everyone else.
Having has EIA for a number of years, this year it has been worse and also impacting on my everyday life. I historically too ventolin before exercise which used to work well but had stopped having an effect. I was sent to a lung specialist who identified that I was allergic to a number of things including pollen and dust mites.
He put me on a cortisone inhaler which after 2-3 weeks had eliminated the asthma I was having during normal day to day activities but I still was getting breathing difficulties when running.
I went back about 10 days ago and had a lung function test which was normal. I have now been prescribed Fenoterol to take 5-10 minutes before exercise and it seems to be working well and I am gaining confidence to exercise again.
I am not sure what it does or what side effects it might have but so far all is good.