Studies Examining Marijuana and COPD
Joan Vos MacDonald
Joan Vos MacDonald is a freelance writer living in upstate New York.
Whether marijuana use increases COPD susceptibility remains uncertain.
As more states legalize marijuana for medical and/or recreational use, people who have been diagnosed with chronic obstructive pulmonary disease (COPD) may wonder if marijuana use is safe or perhaps less harmful to their lung health than smoking tobacco.
While it is estimated that 85% to 90% of COPD cases are caused by smoking cigarettes, studies report conflicting outcomes regarding marijuana use. In the meantime, The American Lung Association, the American Thoracic Society, and the National Institute on Drug Abuse caution the public, particularly those with respiratory problems, against smoking marijuana.
Although the risks of respiratory problems associated with marijuana may be lower than those associated with smoking tobacco, studies to date have shown that it is not risk free.
According to The American Lung Association, the danger has much to do with how marijuana is generally used, as it’s often smoked using pipes, bongs or paper wrapped joints. Inhaling smoke is harmful to lung health, whether it is smoke from burning wood, tobacco, or marijuana. Toxins, irritants, and carcinogens are released when these materials combust, all of which can harm the lungs of those who smoke and those who inhale secondhand smoke. While marijuana smokers may inhale less smoke per day than cigarette smokers, they may inhale deeper and hold the smoke in longer, greatly increasing the amount of tar that remains in the lungs.
According to the American Thoracic Society, regular marijuana smoking is likely to cause lung damage, which could potentially increase a person’s risk of developing COPD. A 2013 study showed that regularly smoking marijuana injures the cell linings of the lungs’ airways, which interferes with the ability to filter out germs and dust.
Research has not yet concluded whether marijuana use affects the immune system, potentially depressing the body’s ability to fight disease. Marijuana use can make an already weakened immune system more vulnerable to respiratory problems associated with aspergillus, a fungus that grows on marijuana and which may be inhaled when marijuana is smoked.
According to the National Institute of Drug Abuse, those who smoke marijuana regularly report more symptoms of chronic bronchitis than those who do not smoke. In younger smokers, marijuana smoking has also been associated with the development of large air sacs, called bullae. Ruptured bullae can leak air and potentially lead to a collapsed lung.
Pharmacists may want to urge patients who are considering marijuana use to discuss that use, and potential delivery systems, with their doctor, especially if they have COPD and/or other breathing problems.
Whether marijuana use increases COPD susceptibility remains uncertain.
Is there a link between marijuana and COPD?
Marijuana is legal for medical or recreational use in several parts of the United States. Researchers continue to investigate whether marijuana can cause or even help treat chronic obstructive pulmonary disease.
Some people use marijuana to relieve chronic pain, and there is growing interest in using marijuana to treat a range of other health issues, including epilepsy and the side effects of cancer treatment.
However, there is also concern that recreational use of marijuana increases a person’s risk of developing conditions such as chronic obstructive pulmonary disease (COPD).
In this article, we examine the links researchers have found between marijuana and COPD.
Share on Pinterest Symptoms of COPD can include wheezing, shortness of breath, and tightness in the chest.
COPD describes a group of long-term lung diseases that includes bronchitis and emphysema.
These diseases cause inflammation, which impairs airflow in and out of the lungs, making breathing difficult.
COPD is progressive, meaning that a person’s symptoms tend to get worse over time. Cigarette smoking is the most common cause of COPD.
Symptoms of COPD can vary in severity but typically include:
- tightness in the chest
- shortness of breath
- unintentional weight loss
- low oxygen level
According to the American Lung Association, cigarette smoking is the cause of around 85–90 percent of COPD cases.
The link between marijuana use and COPD is less certain, and findings have been mixed.
Any association between the drug and the disease seems to relate to the way a person uses marijuana and how often they use it.
Authors of a 2014 study concluded that smoking small amounts of marijuana probably does not cause significant harm, but that heavy use may obstruct the airways and damage lung tissue.
Marijuana contains various chemical compounds called cannabinoids. Two of best-known cannabinoids are cannabidiol (CBD) and tetrahydrocannabinol (THC). THC is the compound that causes the psychoactive effect, or the “high.”
Smoking is a common way to use marijuana, but oils, edibles, and tinctures can also contain CBD and THC. No conclusive research suggests that any of these alternate methods lead to lung damage.
The medical community is unsure whether smoking marijuana increases a person’s risk of COPD.
According to the American Thoracic Society, heavy marijuana smoking is likely to cause lung damage, which could increase a person’s risk of developing COPD.
Many of the harmful and volatile chemicals in tobacco smoke are also present in marijuana smoke. Regardless of the source, smoke, ash, and heat are harmful to the lungs and can damage their lining. This seems to suggest that marijuana smoke is likely to cause COPD.
Also, the manner of smoking can increase the risk of lung damage. A person usually inhales marijuana smoke more deeply and holds it in the lungs for longer than cigarette smoke.
The risk of developing COPD may also depend on how long a person has been using marijuana.
One case study suggests that long-term marijuana use may lead to airflow obstruction and increase a person’s breathing rate, which can affect lung function.
Long-term use may also lead to inflammation and swelling of the bronchial tubes, which can cause symptoms of chronic bronchitis, such as increased mucus production, coughing, and wheezing.
Results of other studies indicate that smoking marijuana in moderation does not cause COPD. Authors of a 2013 review concluded that regular marijuana use may cause a slight increase in airway resistance, which may damage the linings of the lungs and make it harder to breathe.
However, there does not appear to be a definitive link between regularly smoking marijuana and developing COPD.
While smoking marijuana may not cause COPD, it may make symptoms more severe in people who already have the disease.
For example, smoking marijuana can damage the small blood vessels in the airways, which may worsen symptoms such as coughing and increased mucus production.
Smoking marijuana also causes microscopic injury to the large airways, which may make symptoms of chronic bronchitis worse.
Chronic obstructive pulmonary disease (COPD) describes a group of long-term lung conditions. Here, we explore whether marijuana can cause, worsen, or even help to treat COPD, and we examine the research behind these claims.