health effects of cannabis

The chemical delta-9-tetrahydrocannabinol (THC) is the ingredient in cannabis that impacts your brain and body . When you feel the effects and how long they last, can vary depending on how you ingest cannabis. If you smoke or inhale cannabis, the effects can be felt almost immediately. If you consume cannabis as a food or beverage, the effects may be more delayed and can last longer.

Short-term effects

Whenever you use cannabis it can:

  • cause confusion, sleepiness and anxiety
  • impair your ability to remember, concentrate or react
  • increase the risk of accidents that lead to injury or death
  • cause psychotic episodes characterized by paranoia, delusions or hallucinations
  • damage blood vessels due to smoke
  • decrease blood pressure, which can cause you to faint or pass out
  • increase heart rate, which can be dangerous if you have a heart condition
  • lead to increased risk of heart attack

Combining cannabis with other substances

Consuming cannabis with alcohol greatly increases the level of impairment and the risk of injury or death. Combining cannabis with other psychoactive substances can increase a drug’s effects.

Long-term effects

Using cannabis frequently and over a long period of time can have lasting effects on your health. Starting early when you’re younger can cause more harm and the effects may not go away when you stop. Ongoing use of cannabis can:

  • increase risk of dependency and mental health problems
  • harm your memory, concentration, IQ, ability to think and make decisions
  • affect the health of your lungs (when smoked), which can cause bronchitis, lung infections, chronic cough and increased mucus buildup in the throat

You can become dependent on cannabis

Regular and heavy cannabis use can lead to a physical dependency. THC causes an increase in levels of dopamine, the pleasure chemical in the brain. This motivates people to keep using it. You can develop a dependency at any age. Youth are especially vulnerable as their brains are still developing. Frequent cannabis use that begins at a younger age increases the likelihood of dependency.

Mental health effects

Chronic use of cannabis has been linked to depression, anxiety, suicidal behaviours and psychosis. The risk is higher if you start earlier in life and use it frequently. People who are already prone to psychosis are more susceptible if they use cannabis.

Pregnancy and breastfeeding

Using cannabis when you’re pregnant or breastfeeding can harm your baby. Toxins in cannabis are passed on through a mother’s blood to the fetus and in breast milk following birth. Cannabis use during pregnancy can lead to lower birth weight. It has also been linked to longer-term developmental effects in children such as:

  • decreased memory function, ability to pay attention, reasoning and problem-solving skills
  • hyperactive behaviour
  • increased risk for future substance use

Cannabis poisoning

Children, inexperienced adults, or pets may mistake cannabis or cannabis edibles for food. Edibles may contain high amounts of cannabis. Store cannabis in a safe place where it’s out of sight and out of reach. Keep it away from children and pets.

Small children are at a higher risk based on their size and weight. Children who consume cannabis may have severe symptoms and need hospital attention. Symptoms can include loss of coordination, sleepiness and trouble breathing. If you believe your child may have ingested cannabis, call poison control at 1-800-565-8161 or 911. For more information about preventing poisoning, visit the IWK Regional Poison Centre.

Cannabis can make pets very ill and could result in death. Symptoms in pets can include salivation, wobbling, vocalizing, inappropriate urination and vomiting. If you believe your pet may have ingested cannabis, call a veterinarian.