A cpl of years ago I had a chesty cough I couldn’t shift, it was diagnosed as adult onset Asthma. Had the blue and brown inhalers and never once needed the blue, fast forward to last August and I had a chesty cough i couldn’t shift and i called in the private healthcare. After a million tests including the following: Barium swallow, sputum test, MRI with blue dye pumped round (horrible feeling), exercise test all wired up and masked up on bike, various chest x-rays, and a load of lung volume tests. THE CONCLUSION? I don’t have asthma and they have no idea why i am coughing a lot.
It went away after about 6 months and then about 2 weeks ago it started again, so that’s 6 months after the last issue! I think there is just weird crap going around nowadays which is an advancement on the common cold.