CANNABIS
MEDICAL
34 MEDICAL CANNABIS
Rimonabant and CB1 Receptor Antagonists
This may surprise you – but a near perfect antidote to cannabis overconsumption already exists. It has already been tested in thousands of people and at one point was an approved drug in Europe.
This drug is called rimonabant – it is an antagonist (actually an inverse agonist) of the cannabinoid CB1 receptor. In other words, it binds the CB1 receptor (without activating it) and blocks THC from binding and activating the receptor. It essentially works the same way as naloxone does at the mu opioid receptor to reverse heroin overdoses.
Rimonabant was developed as an anti-obesity medication, but it was pulled from the market in 2008 after serious psychiatric side effects were observed. However, those side effects only occurred with chronic dosing. It appears to be very safe after a single dose, and this is all that would be needed to rescue someone from cannabis overconsumption.
A clinical study has already shown that rimonabant blocks the acute effects of cannabis in humans. Although they did not specifically test blocking the effects of a cannabis overdose, there is little reason to think that it would not be effective.
One key advantage of a CB1 receptor antagonist is that you would quickly regain more normal cognitive function. Unlike sedatives, you would not become even more drowsy and have to wait a long time for the effects to wear off.
I doubt there is much financial incentive for a company to get this drug reapproved for cannabis overconsumption. Perhaps the NIH (which already has a sizeable budget for cannabinoid research) could step up to the plate? Or we could get this crowdsourced? These scenarios all seem unlikely to me, but anything is possible.
[July 2017 update] It has recently come to my attention that a natural compound called olivetol may also act as a CB1 receptor antagonist. A company called Undoo has filed a patent for its use in THC overconsumption and created a product for this use. However, there are still no available studies to assess its efficacy.