The Psychoactive Substances Act—which pre-emptively banned new psychoactive drugs (NPS) in the UK—came into force over a year ago. Critics of the legislation are already beginning to see their predictions about the law’s harmful effects being confirmed, but the government has recently doubled down on its defence of the Act. Last week, a Home Office spokesperson stated:

Since we introduced the Psychoactive Substances Act we have seen use of these substances fall significantly, hundreds of retailers shut, and the first offenders convicted.

The use of NPS has indeed fallen from 0.7% to 0.4% among 16- to 59-year-olds since the ban. Although a report released earlier this year by drug treatment charity Addaction suggested that some users are substituting NPS use with more traditional drugs post-ban, few contest the idea that criminalization reduces overall drug consumption to some extent. But the total number of NPS users is only part of the story.

Back when the Psychoactive Substances Act was being debated in Parliament, I highlighted two major reasons for opposing the law: negative impacts on vital scientific research into psychoactive substances and more dangerous NPS consumption.

Those working on developing psychiatric medicines have seen their fears realized. This morning, I spoke to Alex O'Bryan-Tear who works at the Beckley Foundation, which was founded and directed by Amanda Feilding to lead research into psychedelic substances. He explained that:

Research into psychedelics such as LSD and DMT has been tightly regulated since the seventies, requiring stringent safety and ethical approval. But research into all psychiatric medication has been dealt a significant blow by the Psychoactive Substances Act, which makes it possible to commit a serious drug production offence without having any idea, and impacts research into any new medicine.

Candidates for psychiatric medicine get produced and tested in animals to see how they interact with the brain's neuroreceptors. Scientists in the field say that if a new chemical is shown to activate one receptor in particular, the serotonin 2A receptor (formally, 5-HT2AR), that chemical gets shelved immediately. Why? Because it's this receptor that's known to be activated by classic psychedelics, meaning this new chemical could also have psychedelic properties and therefore be illegal to produce. The flaw in this reasoning is that countless chemicals activate the serotonin 2A receptor - including, of course, the brain's naturally-produced serotonin. We don't yet understand why psychedelics have their effect, while other 2A receptor agonists don't. Many classes of medication, such as antidepressants, act on the serotonin system too, so it's vital that we work to understand this system and develop drugs that manipulate it effectively. But the result of drug scheduling laws is that we senselessly discard hundreds of potential medications that could have valuable therapeutic properties.

It also seems as though the NPS varieties available following the ban are, as predicted, more dangerous for users: both in terms of the drugs themselves and the context in which they are taken. With many retailers (head shops) being closed down as a consequence of law, users are left without guidance on safer usage and estimated dosage. Josie Smith, head of the substance misuse programme at Public Health Wales, told The Guardian last week that:

What we’ve seen particularly with the synthetic cannabinoids [a category of NPS] is a reduction in the range that appear to be available on the market, and those that are available are stronger and more dangerous – potentially fatal…

This suspicion that NPS are getting more dangerous is backed up by hard evidence. After a string of incidents in Manchester involving spice—a popular NPS—tests revealed that recent post-ban batches of the drug were ten times stronger than usual. The harms associated with unpredictable, often higher doses of spice have also affected violence in prisons, where the drug is especially popular. This comes as no surprise. Higher potency drugs tend to increase their market share in line with stricter enforcement, since the fixed per-unit costs associated with illegal consumption apply equally to all drug strengths and make high-potency varieties relatively cheaper.

This whole mess could be avoided if politicians took a sensible approach to drug policy by legalising safer, better-understood drugs such as cannabis and MDMA. In the meantime, repeal this wrongheaded law before it can wreak more havoc on young people, the homeless, and prisoners.