Health Risks of Marijuana

The reputation of marijuana is that it is a natural substance, useful for sick people. Is that the truth? Are there health risks to using marijuana, either occasionally or constantly? Let’s take a look at what information is available on the health risks of cannabis, known in the US as marijuana.

Rolling Joint

Some basic information about marijuana:

The active ingredient in marijuana is delta(9)-tetrahydrocannabinol. For short, THC. This is the euphoriant, which means it causes a euphoric state after consumption. The effect is stronger when the plant’s leaves and buds are smoked than when it is ingested.

Marijuana is rolled into a cigarette referred to as a joint, or smoked in a pipe or a bong. A bong is a long, glass pipe that cools the smoke before it is inhaled. The reservoir at the bottom of a bong is filled with water and the smoke passes through the water before reaching the mouth.

Marijuana can also be added to food - brownies have long been a popular vehicle for marijuana. In states that have legalized the medical use of marijuana, there are many “edibles” for sale that have very high doses of THC – tetrahydrocannabinol, the primary ingredient that gets one high. Some edibles like cookies or brownies advise only eating one-sixth of the item for a recommended dose of THC. There are also hard candies, drinks, candy bars, caramels and many other items on the market.

In Morocco, hashish is made by collecting the resins that grow on the buds of the marijuana plant and pressing them together. Hashish usually appears as a dark brown, crumbly block. It too is smoked.

Marijuana is known to causes risks to the lungs, brain, stomach and intestines, and mind. It can also cause birth defects. Here are the details.

Smokey Lungs


When a person inhales marijuana, his bronchial passages open for about an hour and then constrict. A broad study done in New Zealand found that one joint caused the same lung obstruction of 2.5 to 5 tobacco cigarettes. It is common for marijuana smokers to complain of wheezing, coughing and lung congestion.

Changes in the lungs’ ability to protect themselves from infection has been associated with higher chance of illness.

Marijuana can be contaminated with Aspergillus, a type of fungus found on plants, among other places. There are several types of Aspergillus. One type causes allergic reactions for many people, including wheezing and coughing. Another type of Aspergillus is more invasive. It can spread through the body and damage any of the organs, most commonly starting with the lungs. Symptoms of invasive aspergillosis (being infected by Aspergillus) include fever, chest pain and shortness of breath, particularly for people with compromised immune systems.

A British report stated that invasive aspergillosis can be fatal in 90% of cases, depending on which strain of Aspergillus is involved.

The National Institutes of Health report on a man who was smoking marijuana heavily while he was being treated for leukemia. He received a bone marrow transplant and 75 days later, was admitted to the hospital with a diagnosis of aspergillosis in his lungs. Despite treatment, he died.

Another case was reported in 2008 of a Canadian man who was being treated for colorectal cancer. It took three months of antifungal medication to knock out the infection.

While there is a shortage of conclusive research in the area, it appears that heavy marijuana smokers are more prone to lung cancer and emphysema, like tobacco smokers are. When a person smokes both, the risk of emphysema is even higher. Of 92 people who smoked both substances and were examined as part of the New Zealand study, 16% showed signs of emphysema.

A Danish report states that smoking marijuana is associated with a higher risk of malignancies in the airways, that contamination with fungus can lead to infections and that sharing bongs has been associated with the spread of tuberculosis.

These are only a few of the many reports that point to smoked marijuana use posing a danger to the health of the lungs.


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