I had sucked in two huge gulps of the stuff before I started spluttering. I am not a smoker, and the skunk was being delivered in vapour form – two huge balloons of the stuff.

The first balloon was dilating slowly. I increased the strength of my gulps, spluttered more, and after some five minutes had consumed the lot.

I was in a small lab room somewhere behind University College Hospital. I had been told to arrive by 7am because the MRI scanner, into which I would be put, was only available at 8am.

I was part of a Home Office-approved, NHS-supported trial of skunk, under Professor Val Curran, who moved graciously about the place as I became more stoned. A young doctor, Rebecca, was on hand to supervise me.

I am a guinea pig along with others for the trial which has been filmed for Channel 4’s Drugs Live: Cannabis On Trial programme on 3 March.

We had three appointments with Prof Val. At each we had to imbibe two balloons of vapour. One session was to involve street strong skunk that so many consume. Another session was to involve ‘adulterated skunk’ in which the drug’s two worst chemicals had been removed. Another was to involve a placebo.

‘Lost all control’

I knew within five minutes, or so, of taking the first two balloons, that I had taken skunk. What was happening to me outstripped anything I have ever experienced.

I have been passed the odd spliff of cannabis in the distant past perhaps a dozen times. But this of course in a social context, in which you probably only get two or three puffs of the thing. I never experienced anything beyond a slight sense of mellowness.

By the time I was completely stoned I felt utterly bereft. I felt as if my soul had been wrenched from my body. There was no one in my world. I felt I had lost all control and had only the vaguest awareness of who I was and what on earth I was doing. I cascaded into a very, very, dark place, the darkest mental place I have ever been. I was frightened, paranoid, and felt physically and mentally wrapped in a dense blanket of fog. I lost all sense that I was being filmed by Channel 4.

The moment came for me to stumble along the corridor to the MRI scanner for Dr Val to see what the drug was doing to my brain. I lay on the slim hi-tech rack that I knew would take me into what already appeared to me to be a tunnel of terror. I’m too tall for the scanner. The mask over my head kept catching the top of the inside once I’m pushed in.

The terror in me kept rising, my panic chasing hard behind. When you see the film, you can here this distant voice wailing “I can’t stay in here…let me out!”

I’ve worked in war zone but I’ve never been as overwhelmingly frightened as I was right then – and as I emerge from the scanner you see me blearily sitting up and hugging young Dr Rebecca for my dear life, as if she was my mother.

Never again

It took me four hours to come down. Just toward the end I felt a sense of euphoria and expressed it by drawing a pastoral scene on an old box that was lying around in the lab. I drew trees, a fence, a river, and a couple of people – perhaps the very people, trees, and water, that I had felt so deprived of whilst stoned.

I have no idea yet what my experience contributed to the research. Did the other guinea pigs suffer? Did any have some have some other kind of experience? We won’t know until ‘Drugs Live ‘ airs on 3 March.

In the meantime, the placebo had no effect despite the vapour smelling like skunk. The adulterated stuff was just boring. It smelt like skunk, it was a bit foggy and destabilising but I never lost site of my world as I had before.

I would never do it again. I can fully believe this week’s figures that tell us that 25 per cent of all psychosis treated in Britain is associated with smoking skunk.

But what I know, every citizen should know, this is a dangerous, horrible substance.

I had no idea it could be so powerful and terrifyingly mind altering. And I am someone who worked for three years in a drug dependents day centre.

I’ve never believed criminalisation was the answer, I do now believe that education should include a serious and detailed account of what drugs do to your brain.

If many who smoke this stuff had ever seen the physical effects on the brain as displayed through the MRI scanner, they would make a more informed judgement as to what they were doing.

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