I quit smoking in 1991 and developed asthma, sensitive skin and all kinds of allergies..chemical, odors, etc....anyway I started smoking again and  everything went away.  I quit smoking again in January 2017 and my allergies and asthma are back and I actually feel worse than I did when I smoke. Why does this happen?? I have been to he Dr....I am on medication for asthma and allergies again...I am not going to start smoking again... just wonder why this happens