Using cannabis, for example, smoking, vaping, or edibles, has potential benefits and harms. Research is ongoing.
Cannabis (both THC and CBD) is known for its ability to address nausea and vomiting associated with chemotherapy for cancer and stimulate appetite in people living with AIDS. Cannabis also eases pain, improves daily functioning, and has fewer harms than using opioids.
Current explorations of cannabis for treatment of several health conditions show promising results. Cannabinoids have been found to be helpful in dentistry in the treatment of Burning Mouth Syndrome and show potential in the treatment of dental caries (cavities), through prevention of build-up of disease producing plaque on teeth. Use of cannabis in treating dementia is also under investigation. Though this research is in preliminary stages, there is potential for positive outcomes here as well.
Recent research (since 2018) has added nuance to current understandings of some potential harms of cannabis use. Cannabis increases heart rate, blood pressure when laying down and can lower blood pressure when a person gets up quickly from a flat position. This can be risky, especially for those who may have other medical conditions.
Further, cannabis is not recommended for people who have a history of or risk factors for heart disease. Since cannabis can stimulate appetite, it can lead to weight gain, a component of metabolic syndrome (type 2 diabetes, high cholesterol, and high blood pressure), a condition known to have greater chances of fostering adverse cardiovascular events and death in females.
The relationship between cannabis and schizophrenia is well known. Even though cannabis use raises the risk of developing schizophrenia from 1-2%, 1% is significant in a group where the illness can have widespread impacts. In one study, people experiencing a first episode of psychosis were found to be more sensitive to positive "enjoyable feelings" from cannabis as well as negative effects including cognitive (thinking) impairment. Cannabis did not lessen psychotic experiences in this study, perhaps because those experiencing their first psychotic break had higher levels of psychotic experiences.
Another study found that older adults who used edible cannabis products experienced greater balance issues and overall increased feelings of intoxication than non-user controls. Older cannabis users may also be at risk for developing psychosis, poorer attention spans, as well as memory and learning difficulties. An increased risk of heart attack was found in one study of middle-aged African-American males who used cannabis.
The most frequent issues resulting from long term cannabis use are increased blood pressure, bronchitis, and reduced lung capacity in people who smoke it. Some cannabinoids also affect fertility and the immune systems as well and may cause mood problems and anxiety.
As research increases, potential harms and benefits from cannabis use continue to emerge. Each person should consult with their physician or medical team to weigh the positive and negative aspects of using cannabis and find a balance that works for them in their lives.
About the author
The Canadian Institute for Substance Use Research is a member of the BC Partners for Mental Health and Addictions Information. The institute is dedicated to the study of substance use in support of community-wide efforts aimed at providing all people with access to healthier lives, whether using substances or not. For more, visit www.cisur.ca.
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