What Are Legal Highs?

Stacked Spice tropical synergy packs

Legal highs are available as synthetic compounds that mimic the effects of other recreational drugs, or as psychoactive plants that are not illegal. There are huge concerns over safety of synthetic legal highs and there has been great difficulty in the management and control of synthetic highs.

Legal highs arguably pose a greater threat to society than many illegal highs such as cannabis, cocaine, or ecstasy. Legal highs are a relatively new phenomenon whereby someone takes an already illegal high such as THC, manipulates it ever so slightly, and creates a new chemical compound. As the law can’t keep up with the creation of these new substances, they are legal for a small period of time before discovered and prohibited again.

So why might this be more dangerous than legal drugs? To start with, we know more about cannabis, cocaine, meth, and ecstasy than we do about legal highs! When legal highs enter the market, virtually nothing is known about their effects on the human body and psyche. But the medical community has been researching cannabis and other illicit drugs for a long time — so at least they know what to expect!

In this article, we outline the different kinds of legal highs and the controversy that surrounds them. We won’t go through all the laws in all the different countries, so some of these legal highs might be illegal in your country.

What are legal highs?

Legal highs may be one of two things:

  1. A psychoactive plant that is legal, or
  2. A chemical variation on an illegal compound that makes it legal

Legal highs have been in headshops for decades. They are sometimes plants that are legal to cultivate, but have a profoundly psychoactive effect. Other times, they are synthetic copies, if you will, of other better-known intoxicants. More often than not, they are marketed as herbal incenses that are “not for human consumption”, but attract many of those without the resources to buy “real”, “illicit” drugs.

They sometimes come in the form of pills designed to replicate the effects of certain stimulants such as cocaine or ecstasy. Other times, they are herbal preparations that can be smoked and are designed to mimic the effects of cannabis or other hallucinogens.

In some parts of the world, Salvia divinorum, otherwise known as Diviner’s Sage, is legal. But it is one of the most potent hallucinogens when smoked. Depending on where a person lives, salvia can be obtained from headshops or even grown in the backyard. This is an example of a psychoactive plant that is legal in some places.

The majority of legal highs are of the second kind. This involves the manipulation of an illegal compound such as THC, for example, into an entirely new chemical substance. This substance is not yet listed as “prohibited” because it is new, and thus becomes a legal high. This has been done on millions of occasions, all around the world.

Spice is one example of this kind of legal high. It is essentially a manipulation of THC so that it resembles the compound very closely, and though it has similar effects, it is completely different.

A man lying down in front of the bench sleeping

Are legal highs safe?

The short answer is no. And for very obvious reasons. Before a drug becomes approved by any food and drug administration organization, it must undergo rigorous testing for toxicity, pharmacokinetics, and adverse side effects. Legal highs enter the market before this has ever been thought about. Because most of them are marketed as “not for human consumption”, they are not subject to these testing requirements.

Many users of illicit drugs understand the risks associated with their drug use. Legal highs pose more than just the risk to the individual. There are other concerns, such as the exposure of legal highs to undiscerning adolescents, especially because they are typically available in headshops.

Another major concern rests with the medical community. Thanks to decades of research into the effects of cannabis, heroin, cocaine, ecstasy, and other illicit drugs, there are protocols for medical practitioners in the event of an overdose. There is a general understanding of how to manage adverse reactions and events, as well as preventing fatal overdose.

Legal highs enter the market so rapidly and without any scientific inquiry that these protocols cannot be measured. Essentially, the medical community may be helpless to assist someone in the event of an adverse reaction.

There is far less danger associated with legal highs that are psychoactive plants, but have remained legal (such as Salvia divinorum). This is because there is likely some research about these psychoactive plants, or otherwise distinguishable chemical constituents. This is unlike synthetic legal highs which are comprised of entirely new compounds that have never been researched.

An infographic of synthetic cannabinoids

The Spice epidemic

Earlier this decade, the USA, Australia and some parts of Europe confronted one of the strangest “epidemics” in the history of mankind: the Spice epidemic. Spice, sometimes known as ”K2”, “Cloud 9” or “Mojo”, is a kind of synthetic cannabinoid that became increasingly popular in the last decade. And while there have been no known deaths from organic cannabinoids, many deaths have been reported as a direct result of synthetic cannabinoid use.

To give an example, in the USA in 2011, 28,531 visits were made to the ER linked to synthetic cannabinoids. In the same year in New Zealand, 45 deaths were reported as a direct result of synthetic cannabinoids, otherwise known as Spice.

Stacked Spice tropical synergy packs

One of the biggest problems that researchers face with respect to legal highs like Spice is what to do in the event of an emergency. As it stands, treatment is mainly symptom management and supportive care without a general understanding of long-term effects (if there are any).

And in any case, there should be further research to be able to predict adverse health events and treat them effectively. But as one can imagine, this is especially difficult with synthetic legal highs. They enter the market faster than they can be tested, and are often prohibited before they ever enter a laboratory.

A person with blue gloves holding a pack of dried cannabis

Concerns over management of legal highs

There are major concerns over the management of legal highs entering the market. As the model stands in most countries, a substance is, unless specified, not prohibited. For example, most countries have something that resembles a Narcotics Act that outlines prohibited substances. These lists usually include illicit drugs such as amphetamines, cocaine, ecstasy, THC, etc.

Certain substances remain scheduled rather than prohibited. Prescription pharmaceuticals are a perfect example. Outside of scheduled and prohibited substances, everything is considered “fair game” until it’s considered otherwise.

Typically, a legal high will enter the market under the pretence of being a new substance. Once it is discovered as a legal high, that substance is prohibited and all stock is removed from shelves. Usually, the substances will be manipulated slightly again, creating a new one. Within weeks, a new legal high can appear in stores.

Because of the nature of synthetic legal highs, quality and control is virtually impossible. Consumers should be aware that safety and quality are not at the forefront of the minds of those who manufacture synthetic highs.

It is nearly impossible for regulatory bodies to keep up with the production of synthetic highs. It is a perpetuating cycle of prohibition and release of a new compound, and oftentimes, a new compound is created faster than the previous one can be prohibited.

Various herbs against the white background

A discussion on the prohibition of groups of substances

One of the only hypothesized solutions to the phenomenon of legal highs is the prohibition of groups of substances rather than single substances. The current practice of illegal laboratories is the alteration of the molecular structure of a prohibited substance in such a way to create a drug that is not yet prohibited – a legal high. If, however, a whole group of substances were to be prohibited at once, this could truly work against the illegal trade practised by these laboratories.

It is difficult to ban all legal highs at once, though. For one thing, the pharmaceuticals industry and the big chemical companies would object because their products also contain substances that would belong to the prohibited groups of substances.

Secondly, illegal laboratories could easily innovate new groups of substances.

Alternatives: banning the behaviour, not the substance

It may not be effective or efficient to continue the chase after new substances. It requires a lot of resources and is tedious for the organizations in charge of managing these kinds of problems. There may be a possible solution in punishing the behaviour of these illegal laboratories rather than simply prohibiting substances.

In 2017, Australia enforced strict penalties on manufacturers of legal highs. As well as being illegal to sell, the compounds are illegal to produce. Though this may sound militant at first, it can be likened to the cannabis policy in many countries. In many parts around the world, growing cannabis for personal use is legal and acceptable, but trafficking and selling cannabis essentially are not. Thus, it is not the drug itself that is the major problem, but the illegal manner with which they are dealt.

  • Disclaimer:
    While every effort has been made to ensure the accuracy of this article, it is not intended to provide legal advice, as individual situations will differ and should be discussed with an expert and/or lawyer.


5 thoughts on “What Are Legal Highs?”

  1. Mattias Mattsson

    Dont blame Mr JWH!!

    He did not invent it.
    Yes. Compounds made to bind with our cb1/cb2 receptors are not made to be used as a drug. There are soooo many chemical cannabinnoids that has terrifing highs. 1 for example makes you instatly the most stoned you ever been so you want it to go over. Its not pleasent. But for every 30min the effects dubbles. And this goes on for aweek. Morons.
    To those who dont care.
    Plz use only cb2 & mix it w CBD. 🤫

  2. marihuana planet

    I do not think legal highs are safe, it must really undergo testing to its possible side effects or toxicity levels, legal drugs are hitting the industry before this has even been considered. Since most of them are advertised as ‘not for human use,’ these research criteria are not accessible to them.

  3. I agree with you, and every time they ban a legal high – a new one pops up, as usual. In New Zealand they seemed to ban ALL smoke mixes which is good. More European countries should take after that.

    What about legal lean by the way? It seems.. strange. Seems to be all natural.

    1. Scarlet Palmer - Sensi Seeds

      Hi Shiiiing,

      Thank you for your comment 🙂 I’ve never heard of legal lean, will look into it further. I agree, it does seem strange!

      With best wishes,


  4. You made some good points there. I did a search on the topic and found most people will agree with your blog.

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    The Sensi Seeds Editorial team has been built throughout our more than 30 years of existence. Our writers and editors include botanists, medical and legal experts as well as renown activists the world over including Lester Grinspoon, Micha Knodt, Robert Connell Clarke, Maurice Veldman, Sebastian Maríncolo, James Burton and Seshata.
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