This Dr. Christopher's formula contains some beneficial herbs for asthmatic lung health like Marshmallow and Mullein. But personally I haven't noticed any improvement in overall lung function or less need for a rescue inhaler or long term inhaler and found the Lobelia gave me an upset stomach. I read that Dr. Christopher gave Lobelia to his critical asthmatic patients to make them vomit up phlegm. I am not sure phlegm is the problem for every asthmatic. I think the key issue for me is air quality and bronchial inflammation due to my sensitivity to environmental factors like gas heat, wood smoke, pollen, dust, any perfume. I started to take Phytocort by Nutricology instead which appeared to be nominally better at keeping me off occasional Prednisone during asthma flares (usually at the end of a cold when it has settled in my chest). However I noticed a new California Proposition 65 warning label on Phytocort that says: This product contains chemicals known to the state of California to cause birth defects or other reproductive harm. The same for this Dr. Christopher's formula: chickweed has of yet no studies regarding pregnancy and pleurisy root is a danger during pregnancy because of it's contracting properties. A concern if you are of reproductive age and female.