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Cannabis and cancer
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Effects of cannabis

How long do the effects of cannabis last?

  • Effects can last more than 24 hours after you use cannabis. This will depend on:
    • How much and how often it was taken
    • How you take cannabis

Side Effects

This list does not include all side effects.

Short-term side effects:

  • Dizziness
  • Dry mouth
  • Drowsiness
  • Bigger appetite
  • Blurred vision
  • Diarrhea
  • Nausea and vomiting
  • No energy

Long-term side effects:

  • Depression
  • Lack of motivation
  • Issues with learning, memory and attention
  • An effect on your mental health (delusions, hallucination, psychosis, schizophrenia)
  • Higher risk of chest infections if you smoke or vape
  • Tolerance - needing larger doses of cannabis to maintain the same effects
  • Nausea and vomiting

We do not recommend inhaling or smoking cannabis because:

  • We do not fully understand the health effects of smoking it.
  • It will affect your lungs.
  • You do not know how much THC and CBD you inhale.

Problem-use

People can start to rely on cannabis. If you use it a lot, you may start to depend on it.

If cannabis affects your motivation or mental health, please speak to a member of your healthcare team as soon as possible.