Are synthetic cannabinoids more harmful than grown cannabis?

In short - Yes.

While synthetic cannabinoids can produce some effects similar to cannabis, such as relaxation, euphoria and loss of co-ordination and attention,¹³ they impact upon the cannabinoid receptors in our brain with much greater force than THC in cannabis does. This makes them more potent and more capable of producing strong effects on our mental and physical state.^{13, 14}

And there are often many different types of synthetic cannabinoids (even in one batch) – each packet or product is likely to be unique, containing a range of strong chemicals with unpredictable effects.

Serious reported side effects include:

Heart

• chest pain
• fast and irregular heartbeat
• hypertension (raised blood pressure)

Lungs

• breathing difficulties

Kidneys

• acute kidney injury

Brain

• seizures
• stroke

Psychological

• agitation, anxiety and paranoia
• aggressive and violent behaviour
• psychosis

Other

• severe hyperthermia
• breakdown of muscle tissue (rhabdomyolysis)
• vomiting.^{1, 2, 13}

Some of these side effects (like anxiety, paranoia, psychosis) can occur with cannabis use, but this is more common in people who have not used cannabis much before and vulnerable individuals (e.g. someone with a pre-existing mental health condition, or someone with a family history of a mental health condition).¹³

Other synthetic cannabinoid side effects, such as irregular heartbeat, haemorrhagic stroke, hyperthermia and acute kidney injury, are very unlikely to occur with cannabis use – even after taking a large amount.⁴

The effects of synthetic cannabinoids also wear off more quickly than cannabis, which can result in someone taking more of the drug in quick succession, leading to a higher chance of negative effects and dependence.³

There is also growing evidence of withdrawal symptoms that are much worse than cannabis.^{4, 13}

Synthetic cannabinoid use may also produce long-term side effects which are more severe and long-lasting than cannabis – including psychiatric conditions, serious heart issues and behavioural and cognitive impairments.^{13, 15-18}

Deaths from synthetic cannabinoid use

Perhaps the most glaring difference between synthetic cannabinoids and cannabis is that no deaths have ever been recorded due to cannabis toxicity, but drug toxicity has been a direct cause of death in many synthetic cannabinoid-related fatalities.⁴ This is largely because synthetic cannabinoids can be 10 to 100 times more potent than cannabis and can cause acute cardiovascular events (heart attacks etc).⁴

From 2011 to 17, there were 55 deaths in Australia where synthetic cannabinoids were considered a contributory cause. Of all these deaths, accidental toxicity was the most common cause of death.¹

A lot of these deaths occurred in the home where nobody else was there to intervene or call an ambulance. Cases also involved the person suddenly collapsing after experiencing some of the well-known synthetic cannabinoid side effects, such as vomiting/aspiration, delirium, intense agitation, seizures, chest pain and laboured breathing.¹