COPD & Marijuana Smoking: Harmful or Beneficial?

Marijuana legalization is sweeping the country these days. Several states enacted legislation in the last Presidential election year to legalize recreational marijuana. I recently moved to a state where both recreational and medicinal marijuana is not only legal; it's pretty mainstream. In fact, marijuana has a number of common medicinal uses. So, I thought it might be interesting to take a look at whether it could be useful for people who have COPD.

Where Marijuana Is Legal in the U.S.

Only 8 states and the District of Columbia have passed laws legalizing marijuana broadly enough to include recreational uses¹. They are:

• Alaska
• California
• Colorado (my home state)
• Maine
• Massachusetts
• Nevada
• Oregon
• Washington

A number of other states, though, have broad laws allowing for medicinal use of marijuana¹. They include:

• Arkansas
• Arizona
• Connecticut
• Delaware
• Florida
• Illinois
• Louisiana*
• Maryland
• Michigan
• Montana
• New Hampshire
• New Jersey
• New Mexico
• New York
• North Dakota
• Ohio
• Pennsylvania
• Rhode Island
• Vermont
• West Virginia

* In Louisiana, marijuana can only be used in the form of oils, topical applications or other non-smokeable forms.

Most of the remaining states do allow limited use of medical marijuana. However, this is generally under specific circumstances or only for certain types of illnesses, such as epilepsy or very rare conditions. Even in the states where medical marijuana has been broadly legalized, laws vary greatly. And a few states only allow cannabis-infused products such as oils or pills.

It should also be noted that despite laws at the state level, the Federal government still prohibits any legal use of marijuana for either medicinal or recreational uses. So, physicians can only recommend marijuana but are unable to formally prescribe it as therapy.

Is Marijuana Smoking a Risk for COPD?

Unfortunately, we do not have enough research at this time to make a definite judgment on this. However, we do know that inhalation of combustion products, such as tobacco smoke or wood smoke has definitely been linked to respiratory diseases such as COPD and asthma. In fact, tobacco smoking is the biggest risk factor for COPD. So, it stands to reason that inhaling marijuana smoke might also be harmful.

And, in fact, according to a 2016 report on Marijuana use trends and health effects by the Colorado Department of Public Health & Environment: "The U.S. National Health and Nutrition Examination Survey (NHANES) recently found that daily marijuana users have higher levels of toxic combustion by-products than non-users²."

This could be because marijuana smokers tend to take deeper inhalations and hold the smoke in their lungs longer than tobacco smokers. And we also know that marijuana smoke contains many of the same toxins that tobacco smoke has. However, marijuana smokers tend to smoke a lot less daily than tobacco smokers do.

No definite links have been made yet as to whether marijuana smoking could cause COPD, as tobacco smoking can. It does seem likely that in people who already have COPD, smoking marijuana is not going to be helpful. Still, there has not been sufficient research done to know for sure the exact risks of marijuana smoking and COPD health.

Could It Be Helpful for COPD Symptoms?

Research done by a Dr. Donald Tashkin, emeritus professor of medicine at the David Geffen School of Medicine at UCLA, over the past 40 years has revealed that smoking marijuana can dilate the airways and ease the bronchoconstriction typical in COPD³. In fact, the same chemical in marijuana (THC) that causes the "high" experienced by marijuana smokers also results in this bronchodilation.

One theory suggests that THC may also have some kind of immunosuppressant effect in the body. Since the hallmark of COPD is airway inflammation caused by an overactive immune system, this seems hopeful. Unfortunately, there is no conclusive evidence along those lines.

Also, unfortunate is the fact that marijuana smoking has been linked to chronic bronchitis, a closely-related condition to COPD². This would detract from any possible benefits.

What About Marijuana Vaping?

Many people believe that vaping is a healthy alternative to smoking. With vaping (also called vaporizing), the marijuana flower or concentrate is heated in a vaporizing device to a temperature that is below the point of combustion. Therefore, theoretically, the vapor will not contain the toxins that are associated with combustion. This may or may not mean the vaporized marijuana is safe for people who have COPD. The Colorado report referenced above did find that vape-using marijuana smokers did report fewer respiratory symptoms and improved lung function². But these benefits were not measured scientifically.

You may also wonder if edibles might be an option. Dr. Tashkin does not recommend them, as they often contain a synthetic form of THC that's been "manipulated to markedly increase the potency³." And there have been reports of serious complications from edibles, including seizures.

In Summary

We just don't know enough at this time about the effect of marijuana on lung health, good or bad, especially over the long term. Much more research needs to be done to determine if marijuana is helpful or harmful to people who have COPD. One of the complicating factors in this research is that so many marijuana smokers are also tobacco smokers. So, it's difficult to sort out the causative risks.

Marijuana has been greatly publicized as having positive benefits in treating other medical issues, such as severe pain. So, if you are thinking of using it for one of those reasons, you will need to discuss the risks vs. the benefits with your health care team before embarking on that path.