Asthma is a chronic disease that affects the lower airways inside the lungs, also known as the bronchial tubes, which are responsible for carrying air in and out of the lungs. Asthma is extremely common, and every year, more and more Americans are diagnosed with the condition than ever before. In fact, the Centers for Disease Control and Prevention (CDC) estimate that 1 in 13 people in the United States have asthma. The condition is also the most prevalent chronic disease found in children, with pediatric asthma estimated to affect over 6 million children in the U.S. alone.   

Those with asthma know that attacks can be terrifying, and can often start happening without warning. Asthma attacks are often prompted by exercise or environmental factors, such as chemicals, dust, pollen, and other allergens, but an attack can also be caused by a variety of other triggers including respiratory infection or stress. During an asthma attack, the muscles surrounding the airways constrict. This tightening is called bronchospasm, and causes symptoms like coughing and trouble breathing. Feelings of pain or tightness in the chest are also common.

Interestingly, research has shown that cannabis use does not negatively affect the lungs. Instead, certain cannabinoids found within cannabis — namely tetrahydrocannabinol, more commonly known as THC, may actually act as a bronchodilator, reducing respiratory obstruction and increasing airflow to the lungs. In fact, a 2012 study published in the journal American Review of Respiratory Disease showed that on average, those who used cannabis actually displayed better lung function than their peers who did not smoke at all.   

Additional studies also have suggested that cannabis may even specifically help asthmatics and those who suffer from other similar respiratory diseases. In 1975, Donald Tashkin, a professor of medicine at UCLA Berkeley, published a small study suggesting that cannabis may be able to effectively reduce symptoms of asthma. Another study published the following year suggested that the effects of THC may be comparable to salbutamol (aka albuterol), an active ingredient found in many inhalers, in improving ventilatory function. This means that cannabis, or more likely derivatives of cannabis, might someday prove to be a promising treatment for those with asthma and similar conditions. 

As demonstrated by the studies above, there is some evidence that THC may be useful in the treatment of asthma. Still, those living with asthma are certainly not advised to throw away their inhalers in favor of a cannabis-based treatment plan. THC simply cannot compare to a rescue inhaler.  It is critical that asthmatics, especially those with severe asthma, keep a rescue inhaler on hand in case they begin to experience an attack that warrants immediate treatment.  

Although there is not enough evidence to suggest that cannabis or cannabis smoke is related to lung disease or lung cancer, it is important to note that smoking anything is not considered safe. Inhaling cannabis smoke introduces an array of harmful chemicals into the respiratory system that can irritate the lungs and trigger respiratory illness or an asthma attack. Fortunately, many methods of cannabis consumption exist that are just as effective as smoking, but are far  healthier and suitable for everyone, and especially those with asthma and other respiratory conditions. Vaporization of flower (not oil), for instance, is a fantastic way to safely consume cannabis without putting one’s pulmonary health at risk.   

Another key point for asthmatics, is that their asthma need not stop them from reaping the benefits of medical use of cannabis for other conditions. There is ample evidence to support using cannabis for treatment of pain, insomnia, nausea and vomiting, and weight-loss due to poor appetite.  There is some evidence for using cannabis for treatment of depression, anxiety, and PTSD.  Those who have these conditions need not avoid cannabis, if used properly, just because of their asthma.  

Jordan Tishler, M.D. is a physician, cannabis specialist, and faculty at Harvard Medical School. He is also the president of the Association of Cannabis Specialists, and CEO of InhaleMD — a private institute of cannabis medicine. He has spent years assisting patients with cannabis. For more information, or to set up a consultation with the team at InhaleMD, call (617) 861-8519.