Marijuana can act as a "bronchial dilator", opening up the passageways in your lungs when you breathe. Anyone who has ever coughed from a tobacco cigarette will notice a marked different, when coughing from smoking marijuana...since tobacco is the opposite and actually constricts the airways.{Also Proven to help with three types of Cancer and Lukimeia}Today, of the 16 million American asthma sufferers, only those living in California, Arizona and Nevada, with a doctor's recommendation can legally grow and use cannabis medicines, even though it is generally the most effective treatment for asthma.