Determining whether a side effect is cause for concern is not always clear for cannabis consumers. Additionally, assessing the significance of a side effect can prove to be challenging while it is occurring, particularly when anxiety, a common side effect, increases the intensity of an already undesirable experience.

Side effects & adverse events refer to unintended responses to a treatment. Side effects, both positive & negative are defined as predictable responses that occur in addition to the desired therapeutic effect. Side effects while potentially unpleasant, are self-resolving &without long-term health impacts. Adverse events are unexpected & potentially harmful effects.

Adverse events may or may not produce an immediate reaction or may be the result of a secondary occurrence stemming from other side effects such as injuries sustained from falls due to loss of coordination or passing out. They can result from factors such as dosage, timing of onset, duration, drug interactions, or reactions to allergens or contaminants.

Familiarity with side effects & appropriate responses is essential for the safe use of cannabis treatments. For example, side effects associated with excessive THC consumption, often referred to as "THC overdose/greening out,” while extremely uncomfortable & even frightening, will resolve itself over time. On the other hand, consumers may not associate the effects of contamination with cannabis products & continue their exposure which can lead to more serious health impacts.

"Greening Out/THC Overdose" Symptoms

While cannabis cannot lead to a fatal overdose, it can cause an unsettling phenomenon known as "greening out" or "THC overdose" from ingesting an excessive amount of intoxicating cannabinoids, overwhelming the body's capacity to handle the effects."Greening out" occurs more often with edible & concentrated cannabis products & dueto mislabeled products, to novice cannabis consumers who are unfamiliar with their body's tolerance & experienced consumers when trying new products. Mixing cannabis with alcohol, drug interactions, dehydration, insufficient caloric intake & sleep deprivation can increase the effects of THC, which can trigger an occurrence.


Different people have different experiences. One individual may feel stress relief, while another feels overstimulated and stressed, while another feels energized and on-task. There are many factors that impact the effect:

  • Amount used (dosage)
  • Strain of cannabis used and method of consumption
  • Environment/setting
  • Experience and history of cannabis use
  • Biochemistry
  • Mindset or mood
  • Nutrition or diet
  • Type of cannabis used

Symptoms of Contamination

Contamination isn't always immediately apparent & can have lasting health impacts. Symptoms might not manifest right away & in some cases, can take weeks, months, or even years to become evident. These health impacts can affect various body systems, increase the risk of cancer, & complicate underlying conditions. Moreover, the presence of certain prescription drugs can hinder the body's ability to eliminate these contaminants.

If you experience these symptoms, cease using the product immediately & seek medical attention if symptoms worsen or persist.