Mega-dosing vitamin C and taking B-100s for asthma. Also vitamin A has shown to repair lung tissue, use halibut liver oil though as its more universally bioavailable. Taking the inhalers helps the vitamins work as well.
http://realfarmacy.com/plant-based-compound-reverse-lung-damage-associated-copd/
See Cathcart protocol: http://www.doctoryourself.com/asthma.html
Thiamin (B1) is recommended for asthma, too. Egg white have thiaminase which depletes thiamin. Quail eggs don't have thiaminase but they have a huge amount of thiamin, the Chinese use it for asthma.