Marijuana Lungs

Smoking marijuana can damage the lungs, causing inflammation, bronchitis and other health issues. Heavy smoking is associated with more dangers than infrequent smoking. At this time, no research indicates that marijuana causes lung cancer.
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Smoking weed is bad for your lungs. There’s a reason people cough after inhaling marijuana smoke. It irritates the throat and lungs, causing inflammation and damage. Over time, repeated irritation can cause long-term harm to the lungs.

The levels of toxins and carcinogens — chemicals capable of causing cancer — in marijuana smoke are similar to levels in tobacco smoke. Studies have not linked marijuana smoke to increased cancer risk. But smoking weed can cause other serious health effects.

A large portion of people who smoke marijuana also smoke tobacco. This likely increases the risk of lung damage, but it makes determining the exact cause of the damage difficult. Most research on marijuana’s effects on the lungs is preliminary or inconclusive.

We do know that marijuana smoke contains several harmful chemicals. Vaporizers, bongs and other smoking devices with water filters do not decrease the amount of dangerous chemicals in marijuana smoke, according to a 2008 study published in the journal Addiction.

People who use vaporizers have reported fewer breathing problems than people who smoke marijuana in other ways, according to a 2007 study in Harm Reduction Journal. But vaporizing marijuana also releases ammonia, which can cause irritation, asthma and other types of lung problems.

Smoking marijuana regularly is more likely to cause serious lung problems than smoking it infrequently. The risk of serious short-term damage is low for most people, but smoking weed daily can cause major breathing problems.

The effect of marijuana on the lungs hasn’t been fully researched. But studies have found conclusive evidence of several health problems caused by the drug, including marijuana addiction and other long-term health problems.

Short-Term Effects of Marijuana Smoke on the Lungs

Smoking marijuana can cause serious harm in people with pre-existing lung conditions, according to the American Thoracic Society.

People who have the following lung conditions should not smoke marijuana:

  • Asthma
  • Bronchitis
  • Chronic cough
  • Chronic obstructive pulmonary disease (COPD)
  • Influenza
  • Lung cancer
  • Pneumonia

People who smoke marijuana tend to hold the smoke in the lungs for a longer period of time than people who smoke tobacco. This increases the risk of lung damage.

Marijuana smoke usually makes people cough and experience shortness of breath. These effects may last for several minutes or hours depending on the health of a person’s lungs. However, marijuana smoke is unlikely to cause major short-term health issues in most people.

Long-Term Damage Caused by Smoking Marijuana

Lung damage caused by marijuana occurs over time. Most studies on marijuana-related lung damage include people who smoked heavily for several years. The effects of infrequent smoking for several years are unclear.

One of the most common symptoms of smoking marijuana heavily is chronic bronchitis. Bronchitis is a condition caused by an inflammation of tubes in the lungs that carry oxygen. Symptoms of bronchitis include increased mucus production, coughing up mucus and having difficulty breathing.

According to the National Institute on Drug Abuse, other types of lung damage caused by smoking marijuana include:

  • Increased airway resistance
  • Inflammation of the airway
  • Hyperinflation of the lungs

Airway resistance refers to friction in the lungs that makes it hard to breathe. Inflammation causes the lungs’ airways to narrow, leading to increased airway resistance. Hyperinflation occurs when air becomes trapped in the lungs, causing shortness of breath.

Effects of Shortness of Breath

Shortness of breath may seem like a minor symptom, but a lack of oxygen can harm several parts of the body. When the lungs don’t operate efficiently, the rest of the body becomes oxygen deprived.

Carbon dioxide can accumulate in the body when the lungs are weak. This causes chronic fatigue, cough and increased risk of infection. Other organs, including the heart and brain, are harmed by breathing problems.

Effects of Marijuana with Conflicting Evidence

Overall, research on marijuana’s effects on the lungs is still limited. Research consistently links regular, heavy weed use with lung problems, including bronchitis and difficulty breathing. People with pre-existing lung conditions are at risk for major health problems if they smoke any substance, including pot.

Some studies have found an association between marijuana use and bullous lung disease, a condition that can lead to a collapsed lung. However, a conclusive link has not been established.

Small studies have found a possible association between marijuana and lung cancer. But large, sophisticated studies have not found a link.

The long-term effects of infrequent smoking are not well understood. Although marijuana smoke contains numerous carcinogens and toxins, it’s unclear whether marijuana causes cancer or other major lung diseases, such as COPD.

Consuming other forms of marijuana, such as edibles, reduces the risk of damage to the lungs. However, other methods of administration can still cause health problems, including marijuana-related memory loss.

Medical Disclaimer: aims to improve the quality of life for people struggling with a substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare provider.

Chris Elkins, MA
Senior Content Writer,
Chris Elkins worked as a journalist for three years and was published by multiple newspapers and online publications. Since 2015, he’s written about health-related topics, interviewed addiction experts and authored stories of recovery. Chris has a master’s degree in strategic communication and a graduate certificate in health communication.

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