Last verified: April 2026
Definition
A greenout (also written “green-out”) is acute cannabis overconsumption — a cluster of symptoms that can include nausea, cold sweats, pale complexion, dizziness, anxiety, racing heart, and a spinning-room sensation. It is not fatal. There is no recorded case of a lethal THC overdose in medical literature. It is, however, genuinely miserable while it’s happening.
Etymology & Origin
The phrase is a direct analog to “blacking out” from alcohol. The color reference is to cannabis itself — and to the shade of green a person’s face sometimes turns mid-greenout. The term entered broad English-language use in the 2000s and became mainstream with the legal-market era, when edibles made overconsumption much easier. Most commonly caused by edibles eaten too fast (before the first dose kicks in), high-THC concentrates taken by a flower-tolerance consumer, or alcohol combined with cannabis (see crossfaded).
Usage
- “She greened out at the concert and had to sit down for an hour.”
- “I greened out on a 25mg gummy. Never again.”
- “If you feel like you’re greening out, eat something and chew peppercorns.”
The standard folk remedy — chewing black peppercorns — has an actual pharmacological basis: beta-caryophyllene in peppercorns binds to CB2 receptors and may temper a greenout (Dr. Ethan Russo, British Journal of Pharmacology, 2011). Hydration, a dark quiet room, and a trusted person nearby are the other core interventions.
Related Terms
See also crossfaded (greenouts are far more common when alcohol is involved), start low, go slow (the prevention mantra), and zooted.
Call 911 if chest pain is severe, if a person is unresponsive, or if you suspect the product was laced (edibles from unlicensed sources have tested positive for fentanyl in rare cases). For a standard greenout on lab-tested product: time, water, and a safe space are the treatment.
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