Cannabis is a legal drug in Canada. However, it’s important to know and understand all of its effects in order to use it wisely.

Cannabis: a substance that generates interest

Cannabis comes from leaves and flowers from a plant with the same name, also called "marijuana". It is estimated that roughly 4% of the world’s population between the ages of 15 and 64 has consumed it in the past year. Youth are the biggest consumers of cannabis, men using it more than women.

Recreational use of cannabis

Those who consume cannabis are seeking certain recognized positive effects:

• feeling of well-being, pleasure, contentment
• impression of calm and relaxation
• improved mood or self-confidence
• feeling of lightness
• urge to laugh
• etc.

The effects of marijuana usually begin after a few minutes if it is smoked and a little longer if it is ingested. The effects are reversible, but can last several hours.

Therapeutic use of cannabis

In some situations, doctors may recommend the use of cannabis to patients for medical reasons. In fact, its effectiveness has been suggested in scientific studies. It is difficult to draw clear conclusions from current data found in scientific literature with regard to efficacy and safety, but certain results seem promising. This is why cannabis is sometimes used to relieve the following:

• certain types of pain (cancer for example)
• symptoms related to cancer or its treatment (e.g., nausea, vomiting, etc.)
• symptoms of multiple sclerosis (e.g., spasms)

Note that certain medications approved and used in Canada are derivatives of cannabis.

If you are considering the use of medical marijuana, it is important to carefully weigh the advantages and the risks associated with it. Be sure to carefully assess the therapeutic options available to you to make an informed decision. Your pharmacist and your doctor are the best-suited healthcare professionals to help and advise you.

The side effects of cannabis

Aside from the desired effects, cannabis users often experience side effects, such as:

• red eyes
• dry mouth
• increased appetite/food cravings
• nausea
• dizziness, and
• drowsiness

Some adverse effects of cannabis are more concerning, including neurological effects. Among those that are typically well-known:

• decreased attention or concentration
• decreased vigilance and reflexes
• confusion
• memory loss
• altered judgment, and
• onset of temporary psychotic symptoms (hallucinations, false perceptions, paranoid ideas, etc.)

The consumption of cannabis can lead to accidents and injuries. When under the influence of this substance, one must never practise activities that require vigilance, attention or concentration, such as:

• drive a car or any other vehicle
• use machinery
• take care of a baby or a young child
• perform a task likely to jeopardize safety, well-being or the health of others

The impact on health

Occasional or repeated use of marijuana can have repercussions on physical and mental health. Here are some examples:

• heart rhythm disorders (including rapid pulse)
• increased blood pressure
• aggravation of respiratory diseases
• onset or aggravation of a mental disorder (psychosis, bipolar disorder, anxiety disorder, depression, etc.) in predisposed individuals

The smoke produced by the combustion of cannabis contains harmful substances, some of which are carcinogenic.

The impact of cannabis can sometimes be amplified when it is taken with other substances.

The risks of addiction to cannabis

Addiction to marijuana ("cannabis use disorder" in medical language) is very much a reality. The risk of addiction increases along with the consumption of the substance. This is a serious and complex condition that is often difficult to control. Unfortunately, many users underestimate it, which can have adverse consequences on many aspects of their lives.

It can be difficult to make the distinction between moderate and problematic consumption of cannabis. In order to clearly establish the presence of cannabis use disorder, a medical diagnosis must be obtained based on certain well-defined criteria by a competent healthcare professional in the field, such as a doctor or a psychologist.

A withdrawal syndrome, characterized primarily by symptoms of agitation, irritability, insomnia and anxiety, is common upon discontinued use of cannabis.

The risks of cannabis intoxication

Cannabis comes in different formats and in various concentrations. It can be difficult to determine a reasonable dose to take, especially for an inexperienced user. On this basis, the risk of overdose or intoxication cannot be ruled out.

The risk exists not only for users, but for the people close to them who are likely to ingest cannabis inadvertently, such as young children. Even pets can fall victim to a cannabis intoxication.

Cannabis, like any other pharmacologically active substance, has side effects and substantial risks. If you consume it or are considering to do so, we strongly encourage you to speak to your pharmacist or doctor in order to make informed choices and to use it wisely. The situation of each individual is unique and a number of factors must be taken into consideration and carefully assessed.

Don’t hesitate to speak to your pharmacist or doctor if you are concerned about your cannabis consumption or that of a loved one. They will know how to help you and direct you to the appropriate resources. Better not leave anything to chance when it comes to your health!