Chris Coughlan, 33, started smoking cannabis towards the end of his school days. Moving on to ecstasy, cocaine, alcohol and then crack, he became homeless and contemplated suicide before finding help with Teen Challenge, where he now works as a volunteer.
Chris Coughlan from Ilford, east London, helps others with addictions
I came into contact with a lot of drugs through the building trade - it's a tough life out there in all weathers and drugs are an escape.
I was earning good money working as a builder and dealing in drugs, but it got to the point where I was taking 10 to 15 tabs a night and my head was mashed all the time.
The first time I stopped taking cocaine, I realised I had an alcohol problem too. When you're on coke you can drink a lot without getting drunk, and I was becoming very aggressive, starting to lose weight and look bad.
I eventually stopped working and ended up homeless around the West End.
It was a bit exciting at first - no rules, do what you want. I used to think homeless people were scum, but once you get into that trap, it's very hard to get out.
The lowest point was when I woke up sprawled on the street near Leicester Square and people were walking over me to get to work.
One Christmas, when I was squatting in the East End, I went to a Crisis homeless centre in Whitechapel, where I met a tea lady who started to give me the gospel. She was the first person I was ever honest with.
Later, as I was contemplating suicide one night, I looked down and saw the Bible she'd given me and I prayed to God "get me out of this mess I'm in".
So I decided "I'm gonna give this a go".
At first I was suspicious of Teen Challenge - you read about these cults - but that passed after two weeks. They get you up at 7.15am and keep you active. You've got people encouraging you and you're not dwelling on stuff. I needed the discipline.
You don't have to be a Christian to get help from them, you just need to be open to it. I've seen guys come through the programme without finding God.
But coming off drugs is easy, it's staying off drugs that's the hard part, and to do that you need to sort your heart out.
'Toughening the law'
The growth in drugs in the last five years has been 100 times what it was when I was in it.
I go to my local park in Ilford and see 10 and 11-year-olds smoking joints. There's no way I would have come into contact with drugs when I was growing up in Tottenham.
I feel sorry for people living on the estates. I didn't realise how big a problem it was until I came to Teen Challenge.
The downgrading of cannabis to class C is a massive shame. It sends a bad message out to young people.
A lot of it is much stronger nowadays, and I've seen guys of 18 to 21 who've smoked since they were very young and are now accessing mental health services.
Cannabis leads to stronger drugs, so the change angers me a bit. I know the mess it made of my life, so I'm all for toughening the law.
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