He has been using drugs since he was 11 and says he wishes he had never started. This is his story:

"I first got into drugs when I was 11. I started taking cannabis because everyone was doing it at the time.

"Then I got on to hard drugs. I began taking heroin and crack cocaine and have been taking them for the last four years.

"I take them both together. Smoking crack cocaine can make me feel paranoid and I need the heroin to bring me down.

"I get pain in my stomach and legs and I don't feel very well. I feel generally ill.

"My mum and dad have tried to get me off drugs.

"They have been to look for drug dealers and given them my picture and told them not to sell drugs.

"I have tried to get off drugs. I went to rehab for three months, but it did not work.

"I will get off the drugs, but not at the moment.

"I just wish I had not got involved with them really."

Combining drug use

Dr David Best of the National Addiction Centre said treatment did work, but it may not work the first time.

Dr David Best: 'Treatment does work'

"People on the whole get better," he said on BBC One's Breakfast News.

Steve Barker, a community drugs worker, said X's case was typical. Many young people were combining their drug use now, he said.

"They use one drug to manage the effects of another and this can have complications," he said.

Dr Best said drug availability had increased massively in recent years and young people were becoming more sophisticated about using them.

The price of drugs had also come down. The cost of heroin had halved in the last 10 years.

"The cost of drugs is not particularly high and could be funded through perfectly legitimate means," he said.

He added that prevention programmes should concentrate on trying to stop people starting drugs at a very young age as the effects were much worse the longer drugs were used.

He said there should also be an attempt to reduce the barrier between drug use and alcohol and tobacco use.