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What illegal drugs do for pain and depression

Drug researcher David Nutt was sacked as the British Government’s chief drug adviser after clashing with politicians over cannabis. He tells Eloise Gibson that denying cannabis to sick people is ‘outrageous and inhumane’, and shares the latest findings from his trials of LSD.

In a sense, David Nutt was lucky. By the time he was fired from being the head of the British Government’s drug advisory council he was already well-established in his career as a psychiatric researcher.

The sacking hurt, but he's happy it happened – he thinks it opened up the debate on drugs and freed scientists to be honest.

A quick recap: Nutt was forced to resign in 2009 after publicly saying that cannabis and ecstasy were less dangerous to users than booze or cigarettes – and ecstasy was safer than horse-riding.

At the time the British Labour Government planned to upgrade cannabis from a Class C to a more serious Class B drug, so ministers absorbed Nutt's statements about as smoothly as swallowing the contents of an ash tray.

Nutt had evidence to back him up, but the government said it had different evidence. It changed the cannabis law anyway, against the advice of Nutt’s drug committee. Five other members of the committee, the British Advisory Council on the Misuse of Drugs, resigned in protest at Nutt's sacking. The government’s chief science advisor backed his comments about cannabis harm, and it soon emerged that the then-science minister didn’t support his firing, or even know about it. In 2013, Nutt won the John Maddox Prize for scientists who “promote sound science and evidence on a matter of public interest” in the face of difficulty or hostility.

Things worked out fine in the end for Nutt, who is now the Edmund J. Safra Professor of Neuropsychopharmacology at Hammersmith Hospital in Imperial College, London, where he studies, among other things, using LSD to treat stubborn and severe depression.

He spoke at a Brain Health Research seminar at Otago University last week, and next week he'll speak in Auckland about drug reform.

Newsroom asked him how it felt sticking his neck out for science, and how illegal drugs might help treat serious mental illness. [The interview has been edited for length and clarity].

EG: You had a bruising experience in 2009 when you were judged to have crossed the line between communicating science and pushing policy. In hindsight, do you think there's a meaningful line between stating the evidence and advocating for a position?

DN: Scientists have got to tell the truth. We have a body of knowledge built on experimentation and observation. Politics is utterly different, it’s largely about getting re-elected and, sometimes, it’s about trying to do what’s best for the country overall. The tension comes, not from scientists crossing the line, but from politicians lying about the science. If I show you that ecstasy is less harmful than horse-riding and politicians say ‘I don’t care about that, I want to keep ecstasy illegal because it helps me get elected,’ that’s fine. But if they say ‘I want to keep ecstasy illegal because it’s so harmful,’ that’s a lie. There’s a moral debate to have had about drugs but let’s have that debate, not pretend it’s a health debate.

EG: But values and morals affect our definitions of harm, so can we ever keep them out of the debate?

DN: That’s right, but we can develop harm matrices to cover everything, even the fridges and cooking implements we use. We set criteria for safety for those and we can do the same for drugs. But we choose not to because they are a convenient political tool.

EG: You’ve been willing to put your head above the parapet and advocate for evidence-based policy in your field. Some scientists pay a professional or personal price for that. What’s your experience been?

DN: I think it was good that I was quite old when I did it. I’d made my career so I didn’t have a lot to lose in terms of career progression and also, being older, I was pretty wise. I had a lot of information so I could bat off some of the marginal criticisms that someone younger in their career would not. But also I think sacking me was the worst thing they could have done because for the first time it allowed a completely open debate. The people in my role in government were always trying to appease both the government and the scientific community and … all of the sudden I could just tell the truth. For the first time people were hearing experts, government-sanctioned experts in a way, telling the truth and the debate has changed utterly. Ten years ago it was always couched as ‘Oh we’re not sure’ and people wouldn’t come out and say ‘Ecstasy’s less harmful than horse riding'.

EG: Was it worth it for you personally?

DN: Totally. I didn’t want to be sacked, but in the end the debate has moved on more because of my sacking. Governments want scientists to tell them what they want to hear and it’s nice to be able to tell them the truth. The important thing is to put it into the public domain.

EG: The last time you were on the radio in New Zealand, two years ago, you’d just completed brain imaging studies of people on LSD. What have you learned since?

DN: We’re pretty sure we know now how these drugs work in the brain. They change brain function profoundly.

EG: Give us a lay-woman’s summary.

DN: They make the brain much more flexible. Our brains are extraordinarily sophisticated, complicated machines. Every time I say the word ‘machine’ I say it in the same way, because my brain has learned to say it that way. Brains become repositories of actions, thoughts and even sights and sounds that have been acquired and refined over decades as we become a person. Most of brain development is about making sure the brain does the same thing in the same way so that we can make sense of each other. The downside of that is that the brain can become over-constrained. We can get into problems like depression, OCD and addiction because the brain can’t disengage, it gets too involved in negative thoughts (in depression) or too involved in thinking about heroin (in heroin addiction). What psychedelics do is they disrupt, during the period of the trip, that over-engagement and so they allow people to escape from those disorders during the experience. And then also because of the chemistry of these drugs they leave the brain more flexible. So after the trip people can develop new, alternative ways of thinking and potentially overcome their problems.

EG: Do these pathways remain in the brain after a single experience, or do people have to take LSD for the rest of their lives?

DN: I wouldn’t recommend that because the effect would wear off quickly! If you take it more than two-three times the effect disappears, which is why these drugs aren’t addictive. It’s the opposite to cocaine, which very much encourages you to take more. We’ve done imaging studies which show that after psilocybin (magic mushroom) treatment for depression, the brain is more reactive and more responsive.

EG: For how long?

DN: That’s a great question and a difficult one to answer. We’re setting up another study now to see if we can measure the effect at four weeks. We’ve seen the effect the next day, and that flexibility predicts … recovery from depression at four weeks. Some people will stay well for six months. But we need to measure the effect on the brain.

What would be really helpful would be if governments, including your government, would reschedule it (to a lower criminal classification) to make it easier to study. At the moment, magic mushrooms are stuck alongside drugs like crack cocaine in terms of their supposed dangerousness and lack of clinical value and that’s silly. I’m going to be talking in Auckland (on 26 February) about how if we had a more rational approach to drug classification we wouldn’t have any more recreational use but we’d certainly greatly facilitate medical use. We can alleviate enormous problems such as pain with cannabis, addiction with psychedelics. There are many health benefits if we allow people to use and research these drugs … even if you still keep them illegal, but facilitate research by changing their scheduling.

EG: New Zealand is embroiled in what feels like an endless debate on medicinal cannabis use, particularly in terminally ill patients. What are the prospects of patients being able to access LSD if we can’t get cannabis into medical use?

DN: Denying medical cannabis is outrageous and inhumane. It is simply a political decision, there are no health arguments [against it]. Two hundred million Americans have access to medical marijuana and the states that have it, have reduced death rates from opiates and alcohol. But we’ve got to get that through first. Medical marijuana will be the first step and then medical magic mushrooms. LSD is a tougher drug to work with and I think it should still be in the research bag at present. We’ll see some countries moving ahead [with mushrooms and cannabis] and New Zealand and the UK will be left behind and that means people who suffer from these disorders in our countries will be disadvantaged.

EG: There was some research from the Dunedin study showing that people with a particular genetic profile were more susceptible to psychosis from cannabis use. Is there a role for gene testing to screen people out before giving them medical treatment?

DN: You can screen and you can tell them, but you can’t stop them. You can inform people that it will be riskier to use say cannabis medicinally but to be honest it’s a very small proportion. I think it was four subjects in the Dunedin study. I’m in favour of people knowing their genes and the vulnerability their genes contribute to illness and the effects of medicines and drugs but I don’t think you could deny people access to medicinal cannabis if they had an increased risk of psychosis, if they needed cannabis to deal with their pain. The other thing is, people who get psychotic on cannabis stop using it, it’s not like people will keep forcing themselves to take it.

EG: Do people have lasting issues with psychosis, though? You still hear quite genuine researchers raising concerns about psychosis triggered by cannabis use.

DN: What we can say is that in Britain, in the last 50 years, the number of people using cannabis has gone up 20 times and the number of people with psychosis has not gone up at all. So in population terms cannabis has no impact on psychosis. There are individuals who are psychotic who use cannabis and it may worsen some aspects of their psychosis. But the reason they use cannabis is that it makes other aspects of their psychosis better. There is some evidence that cannabis probably brings forward schizophrenia, which is enduring and untreatable. If you have a vulnerability to schizophrenia then smoking cannabis in your teens is quite likely to bring it forward by a year or two, but you were going to get it anyway. It’s not a good thing, and I’m not encouraging people to smoke cannabis. We take the same view with psilocybin or magic mushrooms – we don’t want to provoke psychosis, and there is a risk that mushrooms can provoke psychosis, so we avoid giving it to people with a history of psychosis or a first degree relative with an episode of psychosis.

EG: If you’re screening at-risk people out of clinical trials, where does that leave those people?

DN: Most people don’t have a risk of psychosis. Psychosis is maybe one percent of people, depression is 35 percent. So that’s a lot of people we can treat. And it may be that mushrooms are useful for people with, say, bipolar depression. But I want to go very slowly so that we are very clear about the value of our treatment and how to maximise benefit and minimise risk. History tells us if we are over-enthusiastic, we create problems and backlash. The last backlash [against over-eager experiments with psychedelics] has lasted 50 years.

EG: How important is talk therapy in all of this?

DN: It’s vital, for two reasons. We want to prepare people for the experience of the trip and absolutely minimise the possibility of people having bad trips. And it’s also vital because people have experiences during those trips that they want to deal with. So it’s important that they have a session afterwards. I’m keen on having therapists present to help them. That makes it quite a bit more expensive than traditional treatments, but the positive side is we’re talking about days of this and one single treatment with a medicine, rather than giving a medicine for months, and so in the long run it might be as cost-effective as an anti-depressant.

EG: And cheaper than months or years of talk therapy?

Well, remember that the people we’re treating have failed both those treatments. They’ve failed cognitive therapy and they’ve failed drug treatment so it’s reasonable to go to the next stage even if it is a bit more expensive.

EG: So this is for stubborn clinical depression?

DN: In our trial, they’d all failed [multiple] drugs and cognitive behavioural therapy. One person had failed nine drugs.

EG: What the next trial we should look out for?

DN: We’re doing this clinical trial of psilocybin [and depression] and also a micro-dosing study of LSD to see if the talk is true from Silicon Valley, that micro-dosing makes you more creative and better-functioning. That’s separate from the psilocybin trial. Both new trials will be two years before they are complete.

EG: We’ll keep an eye out. Thanks for your time.