Short-term effects of cannabis use include feelings of happiness, relaxation, and a sense of wellbeing. The effects that a person experiences from using cannabis can vary depending on how much they consume, how they consume it (inhaled vs. edibles), what their mood and mindset is like prior to using it, what setting they are in, and the variety of cannabis they are using.

While there can be good experiences when using cannabis, it can also:

  • increase the risk of a heart attack in the first hour after smoking cannabis
  • trigger a short-term psychotic episode (paranoia, hallucinations), or an anxiety attack if taken in high doses
  • impair your ability to drive a vehicle or operate machinery
  • make it harder to remember things or make decisions

Visit the Lower-Risk Cannabis Use Guidelines for more information on how to reduce these risks.

Taking too much and what to do about it

Contrary to popular belief, it is possible to overdose on cannabis. It is not fatal, but overconsumption can be very uncomfortable and cause sleepiness, confusion, disorientation, clumsiness/loss of coordination, fainting, dizziness, chest pain, fast, slow or pounding heartbeat, panic attacks, loss of contact with reality, paranoia, and seizures.

Overdoses are more common when eating or drinking cannabis-infused foods, called edibles.  Because edibles can take between 30 minutes and two hours to take effect, people sometimes take a second dose thinking the initial dose was not enough. This can result in an overdose.

This is why, even if you have experience using cannabis, it is important to start with lower doses of a product, and to take time between “puffs” or “hits,” or before taking more edibles. It is recommended to wait at least four hours before taking a second serving of edibles to avoid taking too much.

Seek immediate medical attention in case of overdose if experiencing chest pain, panic attacks or seizures.

If you have taken too much and find the effects overwhelming, and you are not experiencing chest pain, seizures, or a loss of contact with reality, make sure you are in a safe place and do not drive a vehicle or ride a bicycle. As the effects of cannabis wear off, you should begin to feel less anxious and uncomfortable.

For lesser symptoms, contact poison control (1-855-776-4766 or 1-855-7POISON), or Health Links – Info Santé (204-788-8200 or toll free 1-888-315-9257) for 24 hour advice.