The use of marijuana for medicinal purposes has been a topic of controversy throughout the medical and political worlds for decades. While marijuana, or cannabis, has been used for thousands of years in healing and treatment, it is currently illegal in many U.S. states. Regardless of its legal status, the question remains whether smoking marijuana is harmful to our lungs, especially for patients living with chronic obstructive pulmonary disease (COPD).

In the last several years, many people with sensitive lungs have turned to vaping with the idea that it is a safer smoking experience. But is vaping safer than smoking? Can COPD patients experience marijuana’s benefits from vapor? Read more about the facts on smoking and vaping marijuana.

The impact of smoking marijuana

Marijuana doesn’t have the exact same negative effects as smoking cigarettes. However, most health experts still warn against smoking the drug. That's because smoking marijuana can harm your lungs or worsen respiratory issues. Even though cannabis rarely contains nicotine, marijuana smoke does contain harmful chemicals.

These chemicals include:

  • airway irritants
  • tumor promoters
  • carcinogens (cancer-causing substances)

Research shows that smoking marijuana also causes visible and microscopic injury to the large airways. This is associated with an increased likelihood of developing chronic bronchitis.

The inhalation patterns when smoking marijuana are different than when smoking cigarettes. Studies have shown that marijuana smokers tend to take larger puffs, inhale more deeply, and hold their breath longer, compared to those who smoke cigarettes. This may be the reason marijuana smokers are at risk for developing a collapsed lung, or pneumothorax. Marijuana smokers also have more cough, mucus, and wheezing compared to people who don’t smoke.

The risk of smoking marijuana with COPD

COPD affects about 30 million people in America. Most cases are caused by smoking cigarettes. Other causes are due to air pollution, chemical exposures, cooking fumes, or genetics. Smoking marijuana may increase your risk for developing COPD. If you already live with COPD, it may worsen your symptoms. In the lungs, smoking marijuana can cause the stretching out of small air sacks (alveoli) into larger, ineffective air sacs called bullae. The risk is higher in male smokers younger than age 45. Bullae can cause shortness of breath. They can also become infected or rupture, causing the lung to collapse. People with significant bullae may require surgery for treatment.

Marijuana smoke may also increase the risk of developing lung cancer, according to American Thoracic Society. It’s important to keep in mind that it’s the chemicals in smoking that can be harmful, regardless of what you’re puffing on. Marijuana contains over 450 different chemicals, some of which are linked to cancer.

“We know that smoking tobacco is very dangerous, leading to COPD or lung cancer. This has been proven beyond doubt,” says Jordan Tishler, MD, a medical cannabis specialist. “Of course, this lead to the concerns that smoking cannabis would do the same.”

Alex Berezow, senior fellow of biomedical science at the American Council on Science and Health, agrees. “The only thing people should be putting in their lungs is oxygen. The reason cigarettes are dangerous isn't because of the nicotine. The tar and other chemicals that cause emphysema or cancer make it so dangerous. Burning or inhaling is a bad idea. That's why we will probably discover that marijuana is bad for your lungs, too.”

The impact of vaping marijuana

An alternative method for taking in marijuana is through vaping. Vaping involves inhaling water vapor through a vaporizer or e-cigarette. Although this method has made a splash in recent years as a “safer” way to smoke, it comes with its own set of risks.

Research shows that vaporizers can release harmful chemicals into your system. Certain chemicals like ammonia can negatively interact with your central nervous system. You also face other risks, like aggravating asthma or causing bronchial spasms when vaping marijuana. The American Heart Association has recently pushed for tougher regulations on selling e-cigarettes. These are similar in nature to vaporizers and can greatly impact youth because of the potential cancer-causing substances they release.

There is still too little research to know the extent of the risk you face by vaping marijuana. Yet, it’s important to remember that vaporizers do not protect you from the harmful effects of the smoke. That means they cannot be regarded as safe to use, according to the American Thoracic Society. If you do choose to vape, Dr. Tishler advises using the safest method possible.

“Not all vaporizing is the same. I recommend vaporizing the whole cannabis flower. The little pen-shaped vaporizers that have become very fashionable and use cannabis oil should be avoided,” he says. “The cannabis in those devices is most often thinned with propylene glycol or polyethylene glycol. Neither of these are safe to heat and inhale. There are alternatives for patients who find loading a conventional vaporizer with ground cannabis is too much for them. I’d recommend looking into a pod-based device, like the upcoming CannaCloud.”

Are there other, safer alternatives?

If you're trying to avoid respiratory risks, there are still ways to ingest marijuana. Edible marijuana products, or “edibles,” do far less damage to your respiratory system. But edibles come with their own setbacks. They are usually slower to take effect and can also last longer than you might want. The dosage is also hard to determine.

This increases the risk of toxic doses and can cause other complications, including:

  • anxiety
  • panic attacks
  • paranoia
  • increased heart rate
  • low blood pressure
  • other physical and mental complications

Life-threatening doses rarely occur but have been associated with death due to heart attacks and sudden cardiac deaths, an unexpected failure of the heart’s electrical system.

There are other ways to take in marijuana, including:

  • sublingual (under the tongue)
  • rectal
  • transdermal delivery (through the skin)

Keep in mind that these methods have little research as to their risks and benefits.

The takeaway

Research in the field looks promising for medical marijuana. However, we still don't know whether medical marijuana is an effective treatment. Beyond that, only 28 states and the District of Columbia allow the use of marijuana for medical use.

If you’re interested in this potential therapy and live in an area where medical marijuana is legal, consider discussing it with your doctor. They can work with you to determine whether this is an option for you.

Your doctor can also guide you through other options and together you can develop the best strategy for you.

Foram Mehta is a San Francisco-based journalist by way of New York City and Texas. She has a bachelor’s of journalism from The University of Texas at Austin and has had her work published in Marie Claire,, and Medical News Today, among other publications. As a passionate vegan, environmentalist, and animal rights advocate, Foram hopes to continue using the power of the written word to promote health education and help everyday people live better, fuller lives on a healthier planet.