Dr Willie Notcutt, Dr Wai Liu, Dr Suzi Gage
The guests from the show return for a Q&A on the marijuana plant and the research into it's medical uses, discussing also the frustrations of working with such a controversial plant. Chris Smith began by asking Willie Notcutt for his take on whether we could minimise some of the negative impacts of cannabis in medical applications...
Willie - Well, I think in a way, we have done Ė this has been done already. I mean, the work that's been done over the last 15 years on the cannabis extract called Sativex has shown virtually no psychoactive effect at all. And certainly, no more than one would expect with an equivalent group of drugs which we use for example for pain management or managing spasticity. So, from that point of view, I think that Ė and sorry, the compound that weíve been using is a mixture, is a blend of THC and CBD which have been known since the early Ď80s. CBD has been known to block some psychoactive effects of THC. Itís been a well-received drug. We found that when used properly as a medicine, we need very low doses of it in controlling spasticity or in controlling pain. Patients, yes, they may get some side effects of dizziness, drowsiness, but nothing equivalent to the sort of effects that your last correspondent was talking about.
Chris - Thank you and Wai Liu, what about the point that some people are asking us, what about the fact that some forms of cannabis when you smoke them for example can be very carcinogenic?
Wai - Yeah. Some people always argue that the carcinogenic properties could be due to mixture with tobacco. whether or not cannabinoids or cannabis themselves are cancerous really the jury's still out. But itís really I suppose this whole idea that the tobacco, you mixed it, which is mixed with it can actually be the one that's causing the cancer.
Kat - And I was going to ask, in terms of things like the one clinical trial that's been done and what people are working towards for using cannabinoids for treating cancer, how would they be administered? Presumably, you wouldn't go to a doctor and they hand you over a massive bifta?
Wai - Hopefully, not. When it comes to clinical trials, I think the ones that are being tested predominantly were ones that were used as a spray. And then the Sativex people have talked about in the past and that's, I think the major one or the ones that people being investigating.
Kat - And we hear also of people for example on the internet using cannabis oil again and I believe so, ingesting it, eating it. is that a good way of delivering cannabinoids into the cancers, into the places where they're needed?
Wai - The problem with ingesting cannabis or in any form is the whole idea that these cannabinoids have different types of chemicals that can actually antagonise one another. And depending on how you get it into your system, you can actually cause more harm than good. That's the reason why people try to purify in a first instance to see if the concepts is correct, that is they are anti-cancerous.
Kat - And I did see something about the risk of increased pesticides and things like that in these oils because they're concentrating them right down. Is that also a risk?
Wai - Depending on the source of these marijuana plants, you can actually get other things interfering with your whole procedure of extraction, and that can cause more problems than you need.
Chris - Suzi, there's an interesting Tweet here which is coming from Jimmy Cullen who says, ďAre cannabinoids getting more research attention because they're a very promising option now or just because cannabis is a hot topic?Ē
Suzi - I think that's a good question, but in terms of Schizophrenia, Schizophrenia is such a debilitating disorder and of all the risk factors that are known about it, most are really, really hard to modify. So, if cannabis is a modifiable risk factor for psychosis or Schizophrenia then it presents a quite unique opportunity. So, that's why I think there's lots of research in it rather than it being a sort of hot topic. But there've been longitudinal studies being ran looking at cannabis since the early 1990s. So perhaps itís getting more media attention now because itís a hot topic. But I think the research has been going on for a long time.
Chris - One Tweet we did have to @nakedscientists, someone saying, ďIs it just frustrating that these chemicals that are so useful and so powerful are also bound up in a Ė to all intents and purposes Ė recreational drug and this is a major frustration in terms of stopping research effort.
Wai - Yeah, that's a very, very good point. The whole idea that itís cannabis that are so-called evil which the psychoactive substance that can possibly be helpful in cancer. And things like Ė I normally say to people is, if we were to call something else, letís call it the BBC drug for the sake of argument, would there more interest in it and if so, where's the problem?
Kat - So, you're really arguing that we should be talking about the cannabinoids, the chemicals themselves as in, we would talk about aspirin rather than white willow.
Wai - Absolutely and itís because itís all a murky, itís all mixed together cannabis; cannabinoids. I suppose to stress that these are cannabinoids. These are agents that have been derived from the cannabis plant which have these anti-cancer properties and that's something that we should really be exploring.
Kat - And people are trying to make synthetic cannabinoids and these kind of chemicals that look like THC or CBD and trying to make those in the lab.
Wai - Yeah, absolutely. And these synthetic ones have been trialled in some cases and in lab based studies, they've also been shown to be effective in certain situations and people argued they're not as effective as the other drugs, the natural stuff. Itís probably because they contain other impurities which are supporting the activities of these THC CBDs but again, people do not know what's going on. To suffice to say, at least cannabinoids, these chemicals do have an effect.