Marijuana and COPD: Is There a Connection?
Chronic obstructive pulmonary disease (COPD) is connected to breathing irritants. For this reason, researchers have been curious about a link between COPD and smoking marijuana.
Marijuana use is not uncommon. A national survey in 2017 showed that 45 percent of high school seniors reported using marijuana in their lifetime. About 6 percent said they used it on a daily basis, while reported daily use of tobacco was just 4.2 percent.
Use among adults is growing as well. A 2015 report noted that marijuana use doubled among U.S. adults over a 10-year span. In 2018, researchers found that the greatest increase in marijuana use since 2000 has been among adults age 50 and older.
COPD is an umbrella term that describes chronic lung conditions such as emphysema, chronic bronchitis, and nonreversible asthma-like symptoms. It’s a common condition in people who have a history of smoking.
In fact, it’s estimated that 90 percent of people with COPD have smoked or currently smoke. In the United States, about 30 million people have COPD, and half of them don’t know.
So could smoking marijuana increase your risk of COPD? Read on to learn what researchers have found about marijuana use and lung health.
Marijuana smoke contains many of the same chemicals as cigarette smoke. Marijuana also has a higher combustion rate, or burn rate. The short-term effect of smoking marijuana may depend on the dose.
However, repeated and consistent use of marijuana may increase the risk of poor respiratory health. Smoking marijuana long-term can:
- increase coughing episodes
- increase mucus production
- damage mucus membranes
- increase risk of lung infections
But it’s the habits that may play the largest role in overall lung health. People often smoke marijuana differently than they smoke cigarettes. For example, they may hold smoke longer and deeper into the lungs and smoke to a shorter butt length.
Holding in the smoke affects the amount of tar the lungs retain. Compared to smoking tobacco, a 2014 review of studies shows that marijuana inhalation techniques cause four times more tar to be inhaled. A third more tar gets into the lower airways.
Longer and deeper inhalations also increase the carboxyhemoglobin concentration in your blood by five times. Carboxyhemoglobin is created when carbon monoxide bonds with the hemoglobin in your blood.
When you smoke, you inhale carbon monoxide. It’s more likely to bind to hemoglobin than oxygen is. As a result, your hemoglobin carries more carbon monoxide and less oxygen through your blood.
There is significant interest in studying marijuana. Scientists want to learn about its medical and relaxation purposes as well as its direct relationship to lung issues like COPD. But there are many legal, social, and practical limitations.
Factors that impact research and results include:
Marijuana is a Schedule 1 drug. This means the U.S. Food and Drug Administration doesn’t consider the drug to have a medical purpose. Schedule 1 drugs are classified this way because they’re thought to have a high chance of abuse.
Marijuana’s classification makes studying its use expensive and time-consuming.
The amount of THC and other chemicals in marijuana can change based on the strain. The chemicals inhaled can also change based on the size of the cigarette or how much smoke is inhaled. Controlling for quality and comparing across studies can be difficult.
It’s difficult to keep track of how much of the active ingredients are consumed. The average person can’t identify the dose they’ve smoked. Most studies also focus on frequency of use but ignore other details that may affect health and a study’s results.
These factors include:
- joint size
- intensity of how someone smokes a joint
- whether people share joints
- use of a water pipe or vaporizer
Even though research is limited for marijuana, smoking anything can be unhealthy for your lungs. Most COPD symptoms aren’t noticeable until the condition has progressed and a certain amount of lung damage has occurred.
Still, keep an eye out for the following symptoms:
- shortness of breath
- chronic cough
- chest tightness
- frequent colds and other respiratory infections
More serious symptoms of COPD go along with more severe lung damage. They include:
- swelling in your feet, legs, and hands
- extreme weight loss
- inability to catch your breath
- blue fingernails or lips
Call your doctor right away if you experience any of these symptoms, especially if you have a history of smoking.
Marijuana smoke has many of the same chemicals as tobacco, but the link between marijuana use and COPD is not as clear. Learn what research says.
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.