"You don't know what you're getting these days ... I could be dead," she said.
Her fears over the declining quality of the drug on sale in clubs and the recent deaths of some young people, including Leah Betts, reflect a growing sense of caution among a number of ecstasy users.
But Kelly, a housing association worker, has decided not to take any more chances and no longer takes the drug. "I didn't have a bad trip as such, but the after-effects just don't make it worth it any more. You don't get depressed like on LSD but your kidneys and back ache for days afterwards.
"It made me tired and listless for ages afterwards, and it can destroy your free time because you don't have energy to do anything else."
Ian, a 19-year-old student from Islington, north London, thought ecstasy was enjoyable but overrated. "I've had it a couple of times at clubs to get me in the mood. It was OK for a few hours but the comedown was not at all enjoyable."
It was endorsed more enthusiastically by Greg, 27, a bookseller from Clapham, south London: "I had my first trip in 1990 and it was brilliant. You feel euphoric and can almost feel the music washing over you.
"The trips can vary though and sometimes it just makes you want to dance. It's good because you don't get any horrible side-effects."
All three agreed that their ecstasy experiences had depended upon where they had got the drug. Kelly said: "I bought mine in a club, which may have explained why it was bad."
Greg and Ian both said that the best way to lay their hands on the drug was from friends.
But despite the caution there are no signs of a drop in the popularity of the drug. Greg said: "It's so popular now and it will remain so until either the music changes or another drug becomes more fashionable."Reuse content