There is heightened public and media interest in synthetic cannabis after the events of the past few weeks, but what exactly are these products, and how do they work?
Synthetic cannabis contains chemicals that mimic the effects of THC, the main component of natural cannabis responsible for eliciting a ‘high’. Hundreds of synthetic cannabis compounds exist, with new compounds emerging rapidly in a game of cat and mouse with regulators as specific ingredients are banned. As such, the precise chemical composition of a single product can differ significantly over time and from batch to batch, leading to uncertainty as to the specific risks associated with their use. These synthetic chemicals have their origins in research laboratories, engineered for potency and never intended for human consumption.
Both natural and synthetic cannabis target a receptor widely distributed in the brain, with an equally wide range of effects on memory, reward, pain and anxiety, to name but a few. If THC could be said to disturb the fine chemical balance of these systems to cause a high, then synthetic cannabis causes a high in a manner likeable to cracking a walnut with a sledgehammer.
The obvious question is, are synthetic cannabis products more dangerous than natural cannabis? The rapidity with which these synthetic cannabis products have come to the market has exceeded the ability of evidence based science to thoroughly assess the potential risks and dangers.
With some synthetic cannabis compounds able to activate their target up to 100 times more readily than THC, the potential for toxicity is high. But it is not only the brain that is at risk. Some medical practitioners are particularly concerned about the increased incidence of acute heart attacks and kidney damage, as well as the seizures and long-lasting psychosis seen in otherwise healthy synthetic cannabis users. These effects are not normally associated with natural cannabis use.
The cells of the immune system are also likely to be affected by synthetic cannabis, since they possess a receptor closely related to the one in the brain through which cannabis acts. A finely balanced immune system with an appropriate mix of stimulation and suppression is required to not only fight off infections, but also prevent allergy, cancer and autoimmune diseases. Natural cannabis generally suppresses the immune system, and although it might be a stretch to suggest that synthetic cannabis could lead to serious diseases, the simple fact is that it remains unexplored.
In fact, no systematic study about the long term health effects of synthetic cannabis products in humans has been published to date. We aren’t even entirely sure at what dose these chemicals become fatal.
The uncertainty of the long-term risks associated with the use of synthetic cannabis products is almost certainly a significant factor contributing to the government’s legislative action. Requiring the manufacturers of synthetic cannabis to prove that their products are safe will require a significant investment of time and money on their part. The hope may be that even if the products can be proven safe, the financial capital required for them to reach the marketplace will be a deterrent.
Even if a product is tested and found to be acceptable, the approval system should at least fix a defined chemical composition for that product and lead to greater clarity of the risks taken by synthetic cannabis users.
Dr Steel completed his PhD on the effects of cannabis on adolescent learning and memory.