“Greening out” describes an acute, uncomfortable reaction to consuming too much cannabis. It is a temporary yet distressing experience, often likened to a “cannabis overdose,” though it is typically not life-threatening. The term is thought to have originated from the idea of “blacking out” from alcohol overconsumption.
What Greening Out Means and Why It Happens
Greening out occurs due to an overstimulation of the body’s endocannabinoid system. Specifically, too much tetrahydrocannabinol (THC) overactivates the CB1 receptors in the brain. THC is the main psychoactive compound in cannabis responsible for its mind-altering effects.
Several factors contribute to greening out, including the potency of the cannabis product. THC concentration has significantly increased over the decades, from about 4% in the 1980s to an average of 15% to 20% today, with some strains reaching as high as 35%. Concentrates and edibles can have even higher THC levels, ranging from 50% to 90%.
Individual sensitivity and tolerance to THC also play a role; a comfortable dose for one person might be overwhelming for another. The method of consumption also influences the experience. Edibles, for instance, have a delayed onset of effects, typically taking 30 to 90 minutes to kick in, with peak effects often occurring two to three hours after consumption. This delay can lead individuals to consume more, thinking the initial dose was insufficient, resulting in overconsumption. Mixing cannabis with alcohol or other substances can also intensify effects and increase the likelihood of greening out.
Recognizing the Signs
Physical symptoms often include nausea, which may lead to vomiting, and dizziness or lightheadedness. Individuals may also experience excessive sweating, paleness, or cold sweats. A rapid heart rate and elevated blood pressure are also commonly reported. Some people might feel a physical immobility, described as being “locked” to a surface, or a general disorientation.
Beyond the physical manifestations, greening out can also present with distressing psychological symptoms. Intense anxiety and paranoia are common, leading to feelings of unease, fear, or mistrust of surroundings. Individuals may experience panic attacks, characterized by sudden and overwhelming fear, or feelings of confusion and a “foggy” mind. In some instances, altered sensory perceptions or mild hallucinations can occur. Feelings of depersonalization, where one feels disconnected from their body or surroundings, have also been reported.
Responding and Prevention
If greening out occurs, immediate steps can help manage the discomfort while waiting for the effects to subside. Finding a calm, quiet, and safe space is beneficial, and having a supportive person nearby can provide reassurance. Staying hydrated by sipping water can help with dry mouth, but avoid caffeine and alcohol as they can worsen symptoms.
Eating a light snack, such as toast or fruit, may help stabilize blood sugar levels. Focusing on deep breathing exercises can also help reduce feelings of panic and regulate heart rate. Resting, and if possible, sleeping, allows the body to process the cannabis more quickly. Symptoms usually fade within a few minutes to a day.
Preventing greening out involves responsible consumption practices. Start with a low dose, especially when trying new products or if tolerance is low. Wait to feel the full effects before consuming more, particularly with edibles.
Understand the potency of cannabis products. Avoid combining cannabis with alcohol or other substances. Consuming cannabis on an empty stomach can increase susceptibility, so eating beforehand is a practical measure.