Most people assume that if a drug is legal then it’s probably safe. However, the truth is that this simply isn’t the case, as many recently created synthetic drugs, commonly referred to as legal highs or new psychoactive substances (NPS), are often legal only because governments haven’t had time to ban them yet. Once outlawed, the manufacturers of these drugs simply tweak the ingredients slightly, labelling their product as an entirely new substance that is then exempt from any prior legislation.

Though these legal highs come in many forms, two of the most common are synthetic cannabinoids and synthetic cathinones, sometimes called “bath salts.” A new video by the American Chemical Society explains what makes these drugs so dangerous.

Synthetic cannabinoids, for instance, contain compounds such as JWH-018, which mimics the effect of THC (the active ingredient in marijuana) by binding to cannabinoid receptors in the brain. Like THC, these molecules generate certain sensations as they interfere with the regulation of mood, appetite, and sensitivity to pain.

However, the main problem is that JWH-018 is much more potent than THC, meaning taking synthetic cannabinoids can often lead to effects that are far more severe than those of marijuana.

Synthetic cathinones, meanwhile, are substances that mirror the effect of a natural stimulant that is closely related to amphetamines. When ingested, they cause large amounts of certain neurotransmitters such as adrenaline and dopamine to be released, giving users high amounts of energy and stimulating the brain’s reward system.

However, synthetic cathinones also block the transporter proteins that vacuum up any unused neurotransmitters in order to regulate their activity. As such, the effect is multiplied, with experts rating some of these “bath salts” as 10 times more potent than cocaine.

Abusing these drugs has been shown to increase the risk of psychosis and other negative health effects, so the bottom line is that these substances really are best avoided.