He could have allergies even after testing,
JANUARY, THAT'S THE BEGINNING OF TREE ALLERGIES..
GOOGLE IT.
I also have a horrible cough that leaves me exhausted.. Chest x-rays, mri's, cat scans, allergy tests only show grass, weeds as allergy related. He could have post-nasal drip causing him to cough. Elevate his bed (pillows under mattress) portion. He could also have "reflux" and should try otc prevacid for acid reflux..stay away from spicy foods.Try using the neti pot (which has done wonders for me vs. medication) which can clear up some of the mucus that is dripping down the back of his throat. Mucinex 12hr.release tablets can help thinning out the mucus also. Dairy products will only make more mucus. Check inside home for "mold" which can be a cause of coughing also. I'm hoping this information will help. Hope the best for you!!!
Has he had a chest x-ray if not that is what I would look into. Also were any of the meds inhaled steriods (like flovent) and was he prescribed any other type of inhaler? Has he been exposed to anything different starting in January?
I hope you get your answers,
achilles2
PS As any part of the homeopathic included a good chiropractor?
http://www.copd-international.com/COPD.htm
Check these symptoms of COPD
If he is not a smoker he could still have it