Short answer: A cannabis overdose, often called "greening out," is not fatal on its own, but it can feel severe. Common symptoms include anxiety, panic, nausea, vomiting, dizziness, fast heartbeat, and confusion. Severe cases bring chest pain, fainting, psychosis, or vomiting that needs medical care.
What a cannabis overdose means
A cannabis overdose means taking more THC than your body can handle. It is not the same as a fatal overdose from opioids or alcohol. The dose, product strength, your tolerance, and how you consumed it all change the reaction. Edibles and concentrates cause stronger and longer episodes because the body absorbs THC differently.
what happens if you smoke too much cannabis
Symptoms
Common early symptoms
- Dry mouth and thirst
- Anxiety, worry, or panic
- Nausea
- Dizziness or lightheadedness
- Fast heartbeat
- Confusion or trouble following a conversation
- Red eyes and sweating
- Shakiness or chills
These effects often peak within 30 minutes when smoked and within 1 to 3 hours when eaten.
Stronger symptoms
- Vomiting
- Intense panic or a feeling of doom
- Short-term memory loss
- Slow or slurred speech
- Feeling detached from your body
- Muscle weakness
Emergency signs
- Chest pain
- Trouble breathing
- Fainting or unresponsiveness
- Seizures
- Severe confusion or paranoia that does not ease
- Repeated vomiting that stops you from keeping fluids down
- Suicidal thoughts
What to do
- Stop using cannabis for the day.
- Move to a quiet room and sit or lie down.
- Drink water in small sips.
- Stay with the person and keep the room calm.
- Track symptoms and time.
- Call 911 if emergency signs appear.
- Call Poison Control at 1-800-222-1222 for guidance if symptoms are intense but not life-threatening.
When to get help
Get medical help for chest pain, fainting, seizures, trouble breathing, or psychosis. Children who eat edibles need care right away. Pregnant people and people with heart conditions should also get advice from a clinician.
cannabis edibles overdose risk
Why edibles drive more cases
Edibles delay the high, so people take more before the first dose hits. Labels list serving size in milligrams of THC, but many products contain several servings. A 10 mg serving can feel mild to a new user and overwhelming to someone else. Store edibles away from children and pets, and keep the package.
Lower the risk
- Start with a low dose, especially with edibles.
- Wait at least 2 hours before taking more.
- Read the label for THC per serving.
- Avoid mixing cannabis with alcohol.
- Use only in a safe place with someone you trust.