Acute Cannabinoid Overdose


There is a pressing need for a reversal agent to counter Acute Cannabinoid Overdose (ACO).

  • ACO can cause acute psychosis
  • ACO accounts for 1.7 million emergency room visits annually
  • Current ACO treatment options only supportive
  • ACO results in days in the hospital if severe

While the opioid epidemic continues to be a national health crisis, legalization of medical and recreational use of cannabis has created an emerging problem: Acute Cannabinoid Overdose (ACO).  ACO is most often associated with consuming edible products containing large quantities of Δ9-tetrahydrocannabinol (THC), the active ingredient in cannabis.

In contrast to smoked cannabis, it can take an hour or more to achieve peak blood levels of THC by consuming these “edibles”, sold as brownies, cookies, chocolates, and candies. This slow absorption often results in people consuming additional quantities because they perceive the edibles are “not working”. Edibles pose a special risk to children because they can easily be mistaken for candies and cookies. ACO is also produced by synthetic cannabinoids (sometimes called “Spice” or K2) that are generally sprayed on plant materials (such as oregano) and smoked.

Synthetic cannabinoids can be much more potent than THC and are particularly dangerous because the amount and type of compound sold is highly variable. Synthetic cannabinoids are structurally unrelated to THC and are not detected by routine blood tests.  While rarely fatal, it has been estimated that there are about 1.7 million cannabinoid-related emergency department visits every year.  

Silhouette illustration of a man filled with smoke

What are the symptoms of Acute Cannabinoid Overdose?

ACO symptoms can include panic and anxiety, feelings of paranoia, agitation, visual and auditory hallucinations, and nausea. These symptoms, often requiring emergency medical attention, can take several days to fully resolve. There are no FDA approved medicines to treat Acute Cannabinoid Overdose. Current treatment is largely supportive and symptom-driven, requiring emergency medical attention and in some instances, hospitalization.  With an increasing number of states legalizing the recreational and medical use of cannabis, the number of ACO related emergency department visits will continue to increase.

Opiant is working on a medicine that will specifically treat ACO

Because the effects of cannabinoids (both THC and synthetic cannabinoids) are produced by activation of specific cannabinoid receptors (CB-1 receptors) in the brain, we have licensed a specific CB-1 antagonist, drinabant, from Sanofi. We are developing this compound for use in the emergency department to reverse the symptoms of Acute Cannabinoid Overdose.