Actually, my Mum has asthma, and the doc told her menthol in cigs would help. It works for her for the same reason they claim it's the worst type for the rest of the population, menthol basically seizes the airway, but for asthmatics, it helps because it usually seizes it open during the inhale, giving them a few hours of easier breathing. So OP, try menthol.
_________________
Every time you think you've made it idiot proof, someone comes along and invents a better idiot.
?the end of our exploring, will be to arrive where we started, and know the place for the first time. - T.S. Eliot