Spice outbreaks of altered behaviour in Manchester and Wrexham have hit the headlines. Scare stories and images of so-called zombie–like behaviour (people being completely intoxicated and sometimes frozen in an unresponsive state), have become commonplace. Although these terms sound perjorative, this is not scaremongering - these behavioural changes show the profound impact that new powerful forms of synthetic cannabinoids can have on users. So what is spice, why do we have it, and what can we do to mitigate its possible harms?

Spice is a slang media term for a range of synthetic cannabinoids that have entered the market in recent years. Their use in the UK really started because the last Labour government decided to target cannabis users to gain the anti-drug vote, or at least to show it was “hard on drugs”. Successive Home secretaries from John Reid to Alan Johnson incentivised the police to catch cannabis users, and to urine-test prisoners for cannabis products. As the penalties for conviction were profound, many turned to legal alternatives, the most popular of which were the synthetic cannabinoids. These are man-made compounds that act at the same sites in the brain as cannabis but are often many times as powerful.

The first synthetic cannabinoids were made in the 1970s as potential medicines, but human testing found them to be so unpleasant that none were ever taken to the market. But three decades on, to bypass the ban on herbal cannabis, underground chemists re-synthesised them and dealers made them available as a smoking mixture called “spice”. This was made by taking a herb – e.g. honeyweed, and spraying a solution of the synthetic cannabinoids onto it. It could then be smoked as a legal alternative to cannabis.

The problems with spice come from a number of factors. The first is lack of any quality control - some parts of the pack may be sprayed more heavily with the solution than others. Secondly scientists know little about the relative safe use of these substances, or the relationship between the dose and the effect. As a result, users may be taking spice at doses well above what they might consume in cannabis. Most importantly, the newer ones have never been tested in animals or humans so there is no data. This is why they are responsible for a rising number of deaths in the UK, particularly in prisoners and the homeless.

The Psychoactive Substances Act of 2016 compounded the problem, because it led to the closure of most “head shops” that were selling relatively milder versions of spice. These shops had an important role in providing reliable sources of spice - owners tested the product to some extent, in order not to harm their regular customers. As predicted from the earlier experiences in Ireland and Poland, shutting down legal sources of psychoactive substances led to a surge in harms from more dangerous ones sold on the black market where customer relations are much less valued.

Another feature of the synthetic cannabinoids is that they are potent in tiny amounts. This potency makes the synthetic cannabinoids very cost effective and also very hard to detect. It took many years before the first spice contents were identified, and then not in the UK but by expert analytical chemists in Germany. In particular, this is why prisoners prefer them.

Synthetic cannabinoids are very profitable drugs. A spice solution costing a few pounds can be sprayed onto a single A4 sheet of paper which, when dried, can be cut up into about 100 units each of which will give a decent “hit” at £5 each. This remarkable profit ratio has led to many prison officers being corrupted into becoming drug mules.

How has the government responded? It began by banning the original synthetic cannabinoids that were detected. Within days, underground chemists had started making analogues of these from the same chemical series. The second-generation were then banned, but the chemists then became more inventive and started making drugs with very new chemical structures. Some of these are extraordinarily potent, and completely untested. Some can cause seizures, heart attacks and death.

The last government’s approach was to try to develop a ban based on core chemical structures. This was brought into law the week before Christmas 2016. Unfortunately, this new law bans many other compounds that are not a bit like cannabis – and many exemptions had to be made to keep many current medicines legal. However, it has banned tens of thousands of useful research chemicals which have no cannabis-like activity and threatens to destroy UK pharmaceutical research unless it is changed.

Yet despite all synthetic cannabinoids now being illegal, we still see growing use because of the attractiveness to the black market and the low cost of an intense “hit”. As well as the homeless, prisoners are being targeted, with some estimates suggesting that three quarters of all prisoners in open prisons use spice regularly. In closed prisons, spice use has also become a huge problem, with prisoners being hospitalised daily because of extreme intoxication. The extreme violence that spice can induce often requires several paramedical teams working together to restrain and admit the person to hospital. This is now placing an intolerable burden on some hospital accident and emergency departments.

What should the government do? First, they should recognise that this problem is not going to be dealt with by simplistic approaches such as more bans, or more severe sentencing of users. Currently synthetic cannabinoids are illegal as class B drugs - which means up to seven years in prison for possession and 14 years for dealing. More deterrence won’t work. We should understand that the targeting of herbal cannabis use is the main reason for spice emerging in the UK. So we should stop testing for cannabis in prisoners and others to encourage a move back to herbal cannabis. Countries with legal access to cannabis, particularly Holland, have a low use of spice. This suggests that we should consider opening up cannabis coffee shops here, to allow safe and legal access to herbal cannabis.

We should also develop known antidotes to spice for use by health professionals. The success of naloxone as a reversal agent for heroin overdose is now well recognised as a way to save lives. Last year I wrote to the Health and Home secretaries with suggestions as to how similar antidotes for synthetic cannabinoids could be developed. Their replies revealed a complete lack of appreciation of the magnitude of the synthetic cannabinoid problem, and a lack of interest in the idea of an antidote. Worse still, in December 2016, the Home Office rejected appeals to make the only herbal antidote to cannabis (THCV) legal, despite its having no psychoactive properties when used orally. We need scientific advisory bodies like the Advisory Council on the Misuse of Drugs and the Academy of Medical Sciences to take up this challenge and push for research funding to develop antidotes.

Spice is a problem that is largely of our own making. History tells us that prohibition of one drug often leads to the emergence of more toxic alternatives. The ban on smoking opium led to injecting heroin, alcohol prohibition in the USA led to deaths from hooch and methanol, cocaine enforcement led to crack, the mephedrone ban led to naphyrone and so on.

We need a much more holistic and mature approach to drug use than simply banning everything. Heroin has been illegal for recreational use for a hundred years. Yet the latest data we have shows the highest ever number of heroin-related deaths in the UK. Prohibition of synthetic cannabinoids is not working, and will not work, as the sole approach to this growing and very worrying problem.