First Aid for a Cannabis Green Out: Steps and Warning Signs

What a green out is

A green out is acute overconsumption of THC, the main psychoactive compound in cannabis. Symptoms start within 30 minutes of smoking or vaping. Edibles take 30 to 120 minutes to begin and 2 to 3 hours to peak. Effects last 4 to 6 hours, and sometimes longer. Signs include nausea, vomiting, dizziness, sweating, pale skin, fast pulse, low blood pressure, anxiety, panic, paranoia, and confusion. A green out is uncomfortable but it is uncommon as a medical emergency. Cannabis alone has not caused a fatal overdose in an adult. The real risks are falls, vomiting while asleep, heart strain, and accidental high-dose edible ingestion by children.

how long does a green out last

First aid steps

1. Stop all cannabis use. Do not smoke, vape, dab, or eat more THC. More THC adds to the problem.
2. Move the person to a quiet room. Dim the lights. Keep the room cool.
3. Choose a position. Sit upright during nausea. Lie on the side if the person is sleepy or vomiting, so the airway stays clear. Raise the legs if the skin is pale or the person feels faint.
4. Speak in short sentences. Repeat the same facts: "This is THC. It peaks, then it passes. You are safe. I am staying."
5. Offer water in small sips. Do not force food or drink during vomiting.
6. Offer sugar if the person has not eaten in several hours and feels shaky. A sweet drink or hard candy can help. Low blood sugar can copy green out symptoms.
7. Skip folk remedies that need more smoke or vape. Black pepper and citrus peel are common folk cures. Evidence is thin. They do not treat the cause.
8. Do not give alcohol, caffeine, or other stimulants.
9. Stay with the person. Check breathing and response every 15 minutes.
10. Allow sleep only when breathing is normal and the person can be woken.

Call 911 if any of these appear

• Chest pain or chest pressure.
• Breathing that is slow, shallow, or has stopped.
• No response, or the person cannot be woken.
• Seizure.
• Vomiting that will not stop, or vomit breathed into the lungs.
• Pulse above 150 beats per minute, or an irregular pulse.
• Hallucinations that lead to risk of injury, or talk of self-harm.
• The person is under 18, pregnant, or has heart disease.

For a child who ate an edible, call Poison Control at 1-800-222-1222 first, then 911 if symptoms are severe. Do not wait for symptoms to start. Edibles release THC for hours.

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What to expect

Peak intensity lands 1 to 3 hours after an edible dose and 10 to 30 minutes after inhaled THC. Most episodes ease over 2 to 4 hours as the drug clears. Sleep ends many episodes. Symptoms can return in waves, so keep checking the person until they are steady on their feet.

what causes a green out

Lower the risk next time

Start with 2.5 to 5 mg of THC in an edible, then wait 2 hours before any second dose. Check the label for total milligrams per package, not per piece. Keep THC products in a locked box away from children and pets. Choose a lower potency flower or vape. Keep CBD on hand. Some users report that 25 to 100 mg of CBD eases the edge, though the evidence is limited. Eat before use. Avoid mixing cannabis with alcohol.