A British woman who used cannabis for a month as part of a BBC documentary says it was a horrendous experience. It left her paranoid and frightened, she says.
Nicky Taylor, from Kidderminster, took part in the experiment in Amsterdam, where the drug is legal. She also became psychotic after an injection of an active ingredient of cannabis.
She said that the effects of a powerful version of the drug called "skunk" were "absolutely horrendous", though not long-lasting. This is not the first time Nicky has become a guinea pig - other programmes have seen her binge drinking, and undergoing plastic surgery, reports the BBC website.
Although scientific research has firmly linked cannabis use with health problems, the UK has, according to UNICEF, the third highest rate of use among young people in the Western world.
Although she had previously used cannabis two decades ago at university, Nicky said that she wanted to find out what would happen to her children if any of them went on to take today's version of the drug.
Some modern varieties are said to have up to five times higher levels of the active ingredient THC.
After taking a job at an Amsterdam coffee shop she smoked different varieties and strengths on a daily basis.
Her experiences with "skunk" cannabis, she said, made her feel "irrational and paranoid".
"Some nights I couldn't sleep at all, and would be pacing my room, becoming more and more paranoid and thinking everyone I'd met at the cafe, as well as the BBC crew, was talking about me."
Although weaker types of cannabis did not have the same effect, she said that her ability to function properly was compromised, making it even more difficult than usual to perform tasks such as putting together flat pack furniture.
"The drug totally wrecked my mind," she said. "There is no way I would want to repeat it again. Nothing made much sense to me any more."
Another noticeable effect of the drug was on her appetite - she said she gained half a stone over the course of the month due to cravings for sweet and salty snacks.
After the month was over, she visited scientists at the Institute of Psychiatry in London, where she was injected with THC alone, and THC with cannabinoid, the combination found in less potent cannabis. After the pure THC, she had a severe psychotic episode.
"I thought that the reasearchers conducting the episode were characters from a horror film, "I was thinking about jumping out of a window."
A psychological score taken during the experiment suggested that the level of her psychosis was greater than that found in some people suffering a schizophrenic attack.
Fortunately, after the end of the month-long experiment, she has suffered no long-term effects, but has vowed to try to keep her children away from the drug.
However, she said a sober public debate was needed about cannabis, as there was growing evidence that it had potentially useful medical applications.
"This is a complex plant, it can do an awful amount of harm, but it can also do an awful amount of good," she said.
"On one hand you have people who think it is the spawn of the devil, and then you have people who think it's fantastic, so nobody ever gets to sit down and actually talk constructively about what we should do with the problem."
Martin Barnes, chief executive of charity Drugscope, said that most evidence about the potential health harms of cannabis had been gathered using lower-strength cannabis varieties.
"The average potency of cannabis available in the UK has increased, and while it is intuitive that greater harm potentially will arise from stronger forms of cannabis, people shouldn't assume that only the stronger types are harmful.
"A big issue is also the longer-term problems which may arise from cannabis use."
A spokesman for Addaction, the drug treatment charity, said cannabis was easily obtained, and normally the first drug used by young people.
She said: "Using the drug can provoke the onset of psychosis or worsen existing psychotic illness - so for people with a history of mental health problems or depression, taking this drug is not a good idea.
"What we need is open, realistic education and information on the associated risks of cannabis use and to make sure high quality treatment is available to all those who need help."