Synthetic cannabis - what is it exactly, and is it dangerous?

Despite the name and the heavy marketing, synthetic cannabis has almost nothing in common with the natural plant, Cannabis sativa L. 

But what is synthetic weed (Spice, Kronic, K2, etc.)?

It doesn’t look like cannabis, it doesn’t smell like cannabis, our bodies don't react to it in the same way as when we take medical cannabis, and the scientific research into synthetic cannabis (backed up by a large body of anecdotal evidence) shows that it is simply not a safe alternative to legally prescribed medical cannabis, or even, unregulated ‘street weed’. 

In fact, where cannabis (when legally prescribed and monitored by a specialist) is classed as a viable medical treatment option, synthetic weed is the opposite. 

What is synthetic cannabis?

Marketed as herbal incense, or "herbal smoking blends" under punchy brand names like Spice, Kronic, Scooby Snax, Black Mamba and K2, synthetic cannabis (or neocannabinoids) is a mix of dried herbs (usually damiana, mullein, or marshmallow leaf) soaked in a liquid containing a lab-made synthetic cannabinoid designed to mimic THC, the main psychoactive compound in cannabis.

And alongside the colourful, oftentimes child-focused graphics, there will usually be (in tiny, almost unreadable font) a warning label along the lines of “not suitable for human consumption”.

A short history of synthetic cannabis use in the UK

Synthetic cannabinoids were originally developed as research drugs in the 1960s, but by the early 2000s, they started to creep into street markets - first in the USA, and then in the UK and the rest of the world. 

By the mid-2010s, synthetic cannabinoids were being seized in large quantities here in the UK and linked to a worrying increase in hospitalisations, mental health crises, and even sudden deaths.

Is synthetic cannabis legal in the UK?

No. Synthetic cannabinoids are not legal in the UK, and haven't been since 2016. 

And although usage started to decline slowly after the sale of all synthetic cannabinoids was made illegal under the UK’s Psychoactive Substances Act in 2016 (and during COVID, when importation slowed), synthetic cannabis is far from gone. Government seizures of synthetic cannabis rose by 60% in the last year alone.

Even though it is illegal, It’s not particularly hard to find. While you won’t see it being openly sold in petrol stations and tobacconists any more, it is still available online - and unfortunately, it is still negatively affecting lives.

How does synthetic cannabis differ from natural cannabis?

Cannabis and synthetic cannabis are not the same thing whatsoever. 

The main reason they are still lumped together is the fact that the words ‘cannabis’ ‘weed’, and/or ‘marijuana’ are tacked behind synthetic. This is a pure ‘black hat’ marketing decision. 

You can think of it in the same way you would if you compared a prescription medicine to mystery pills sold in a nightclub toilet.

Prescribable pharmaceuticals take years of testing, regulation, and clinical oversight before they ever reach a patient. Synthetic cannabis products, on the other hand, are made in unregulated labs, constantly altered to stay one step ahead of the law (with zero concern for the consistency of the products, and even worse, how safe they are).

While synthetic weed products claim to mimic THC, that is simply false.  

How synthetic cannabinoids behave differently from THC in the body

THC, a natural cannabinoid produced by cannabis plants, is a partial agonist of the CB1 receptor, meaning it can bind to the receptor but only activates it to a limited degree - think of it like a dimmer switch rather than an on/off light switch. 

Synthetic cannabinoids are often full agonists. They slam the receptor into full activation mode, often with far greater potency than anyone would ever want or need to experience, either recreationally or for therapeutic needs.

This results in effects that users aren't expecting, and some of these effects are extremely disturbing.

How synthetic cannabinoids affect the body and mind

Instead of offering patients potentially positive therapeutic effects, like pain relief, help with sleep disorders, and improved mental health outcomes, synthetic cannabinoids can trigger intense, sometimes dangerous, and often frightening reactions. 

The side effects of synthetic cannabis aren’t just uncomfortable - they can be dangerous, unpredictable, and in some cases, life-threatening.

The physical and mental effects of synthetic cannabis

• Visual memory, attention, and executive function are heavily affected.
• Overwhelming anxiety, hallucinations, severe paranoia, memory loss, seizures, and in some cases, a complete break from reality can and do (all too regularly) affect people who smoke synthetic marijuana.
• Synthetic weed has also been linked to lasting insomnia, psychosis, suicidal thoughts, and unresponsive states where users ‘freeze’. Physically, it can cause worryingly high blood pressure, chest pain, and measurable harm to the heart and kidneys, including heart attacks and acute kidney failure.
• Long term usage has also been shown to cause structural changes in the brain - including white matter loss, hippocampal shrinkage, and reduced frontal lobe activity.

The overstimulation of the CB1 receptors in the brain and throughout the central nervous system changes how our neurotransmitters function, triggering toxic cellular responses through more than just the endocannabinoid system signalling pathway - the MAPK, Akt, and ceramide cascades.

These signalling pathways are involved in regulating inflammation, cell survival, and stress responses, so when they’re over-activated by synthetic cannabinoids, the result can be widespread cellular dysfunction and damage across multiple organ systems.

What is withdrawal from synthetic cannabis like?

Synthetic marijuana withdrawal symptoms are, in one word, brutal. 

It's often described as being worse than coming off heroin, with side effects that include:

• Intense vomiting and nausea
• Cold sweats and chills
• Severe insomnia
• Muscle pain and shaking
• Extreme agitation, which can lead to heavy aggression
• Mental breakdown
• Suicidal thoughts
• Total loss of appetite
• Crushing fatigue and paranoia

In this fascinating (but also heartbreaking) study, many users share their experiences both while using synthetic weed and just how horrible it was to come off it.

Some spoke of blackouts, seizures, or terrifying hallucinations. Others described the way it crept into their lives, with it being so cheap and so easily available, only to spiral into dependency. 

And many mentioned the fact that there is no standardised formal treatment protocols, which only makes coming off of synthetic cannabis that much harder - more research and clinical guidance is urgently needed.

“I managed to get off it [SCs] there about 3 months ago now. That was awful. It [was] literally like being in hell. Your skin is on fire, your head is just far gone, like even in the hospital, like I ended up over there, it was that bad, and I was clawing at the ground and trying to rip my hair out and all and they jabbed me with diazepam, like the strongest stuff they had, and I was still losing the plot, so it’s a lot stronger than anything else I’ve ever came across in my life”

“Every time you smoked it you would have been sick but still you had to smoke it . . . The withdrawal is worse than any drug on the planet like. It’s like a withdrawal from heroin with no substitute, the withdrawal with that. It’s the heaviest thing to come off.”

Comparing natural cannabis and synthetic cannabis: What’s the difference?

The dangers of synthetic cannabis: What we know now

Synthetic cannabis is not a weaker or ‘safer’ form of cannabis, no matter if cannabis is legally prescribed or sourced through illicit avenues. If the above information hasn’t clearly shown that synthetic cannabis should be avoided at all costs, then consider this the final nudge. 

Synthetic cannabis should never be taken, either for therapeutic or recreational reasons. It’s an unpredictable, overly potent, and often deeply harmful class of substances that hijacks the brain and body in ways natural cannabis simply does not.

If you’re concerned about your own synthetic cannabis use (or worried about someone close to you), please don’t try to face it alone. Speak to your GP, reach out to a support service like Talk to Frank or Release, or contact a local drug support organisation. 

Help is available, and recovery is definitely possible.