Greening out is the slang for consuming too much cannabis and feeling unwell: anxiety or panic, nausea, dizziness, a racing heart, sometimes vomiting. The Ontario Cannabis Store uses the term itself and notes it is generally not life-threatening, but can come with many unpleasant symptoms.[1] Here is what it feels like, what to do, when to get help, and how to avoid it, especially with edibles.

Key Takeaways

  • Greening out means overconsuming cannabis. It is generally not life-threatening, and the effects are generally temporary.[1]
  • Get medical help for chest pain, panic attacks, loss of contact with reality or seizures.[1] If you feel unwell, call 1-844-POISON-X (1-800-463-5060 in Quebec), call 9-1-1, or go to your nearest hospital.[2]
  • Edibles are the usual trap. They take 30 minutes to 2 hours to start working, and that delay can lead people to take more.[2]
  • Alcohol makes it worse. Mixing can increase the risk of unpleasant effects.[1]
  • No driving for up to 24 hours after consuming, the Ontario Cannabis Store advises.[1]

On this page

What greening out is

The Ontario Cannabis Store puts it simply: overconsuming cannabis is sometimes called greening out, and although it is generally not life-threatening, it can come with many unpleasant symptoms.[1] Health Canada describes the same thing as overconsumption that can lead to cannabis poisoning, with effects such as panic or anxiety, paranoia and hallucinations.[2]

Symptoms

The Ontario Cannabis Store lists these signs of consuming too much:[1]

In the bodyIn the mind
Nausea, sweatingAnxiety or paranoia
Dizziness, faintingConfusion, disorientation
Sleepiness, clumsiness, restlessnessPanic attacks
Chest pain, abnormal heartbeatLoss of contact with reality
Seizures

It adds that you may experience severe anxiety and paranoia, vomiting and, in rare cases, an acute psychotic episode.[1]

When to get help

Seek immediate medical attention if you have chest pain, panic attacks, loss of contact with reality or seizures.[1] Health Canada's advice if you overconsume and feel unwell: call 1-844-POISON-X (1-800-463-5060 in Quebec), call 9-1-1, or go to your nearest hospital.[2]

What to do if you green out

For milder symptoms, the Ontario Cannabis Store suggests:[1]

  • Eat a snack. It may help, and it is a distraction.
  • Drink water. It helps with dry mouth and may help you stay calm.
  • Shift your focus to calming music, a show, a quiet space or someone supportive. Dwelling on the negative feelings can make them worse.
  • Don't drive or operate heavy machinery for up to 24 hours after consuming.

The effects are generally temporary.[1]

Why edibles cause it so often

The timing is very different. Health Canada says inhaled cannabis takes effect within seconds to minutes and lasts 2 to 4 hours, with some effects lingering 12 to 24 hours. Eaten cannabis takes 30 minutes to 2 hours to start and lasts 4 to 8 hours.[2] It warns that the delayed effects of edibles may lead to overconsumption.[2]

Strength adds to it. Edibles sold in licensed stores are capped at 10 mg of THC per container,[3] while many edibles listed by online dispensaries carry far more per package, so check the amount per piece, not just the package. Our edibles page compares them by price per 100 mg of THC.

Cannabis and alcohol

The Ontario Cannabis Store advises avoiding mixing cannabis with other drugs, including alcohol: mixing can increase the risk of unpleasant effects, and cannabis can amplify the effects of central nervous system depressants such as alcohol.[1] More in what being crossfaded means.

How to avoid greening out

  • With edibles, wait. Give it the full 30 minutes to 2 hours before even thinking about more.[2]
  • Check the strength per piece, especially on products from online dispensaries.
  • Skip the alcohol.[1]
  • Be careful with concentrates. They are much stronger than flower; see honeycomb wax and other concentrates.
  • Know your tolerance. See how cannabis tolerance works.

FAQ

What does greening out mean?
Consuming too much cannabis and feeling unwell. The Ontario Cannabis Store notes it is generally not life-threatening but can come with many unpleasant symptoms, such as anxiety, nausea, dizziness and a racing heart.
How long does greening out last?
The effects are generally temporary. Health Canada says inhaled cannabis lasts 2 to 4 hours, with some effects lingering 12 to 24 hours, and eaten cannabis lasts 4 to 8 hours.
Can you overdose on weed?
Overconsuming is generally not life-threatening, but it can cause serious symptoms. Get immediate medical help for chest pain, panic attacks, loss of contact with reality or seizures, and call 1-844-POISON-X or 9-1-1 if you feel unwell.
What should you do if you green out?
Eat a snack, drink water, and shift your focus to something calming. Don't drive for up to 24 hours. Get medical help for chest pain, panic attacks, loss of contact with reality or seizures.
Why do edibles make people green out?
They take 30 minutes to 2 hours to start working, and Health Canada warns that the delay may lead to overconsumption.
Is greening out worse with alcohol?
Mixing cannabis with alcohol can increase the risk of unpleasant effects, and cannabis can amplify the effects of alcohol.

References

  1. Ontario Cannabis Store. Can You Consume Too Much Cannabis? Cannabis Safety Answers. ocs.ca
  2. Health Canada. Consumer information: Cannabis. canada.ca
  3. Health Canada. Guide on composition requirements for cannabis products. canada.ca

For adults 19+. General information, not medical advice. In an emergency, call 9-1-1.