This is what it was like for prisoner who became addicted to spice in prison

"I landed in jail and took some weed with me and two little phones," explains Tom.

That's not his real name. He's 33 and served a four-year sentence for dealing cocaine.

"I smoked my weed on the first night in the induction cell and wanted to swap one of my phones for a half ounce of weed but I ended up getting half an ounce of spice," he remembers.

"I didn't know what it was. That was the first time I came across it."

Tom says he started using spice more and more as it become an addiction.

"When I had nothing else to buy it with I was robbing people, slashing people, hitting people with cups over their heads just to get the drug," he admits.

"I was asking my family and friends for £50 every day. It spiralled out of control and I ended up spending £12,000 in two years."

If the government doesn't tackle the supply of drugs properly, its big shake up of how prisons are run is set to fail, according to drug experts Volteface.

Their study has found new psychoactive substances - like Spice - have become commonplace in jails and are contributing to record levels of suicides, violence and self-harm.

Results from the study don't surprise Tom: "It's everywhere. You'll never stop it getting into jail."

Tom says he lost a lot of weight while he was hooked on spice and he struggled sleeping.

"Everyone's got mobiles in jail," he says. "You'd phone your people, give them the bank details and they'd go to the bank and pay it in.

"They'd then phone their people and make sure it's been paid in. If it's been paid in you'd get the drugs."

He's been out of prison for four months now and doesn't want to go back to the addiction he had, where he describes having "blood coming out of my ears."

"I haven't touched a single drug, a single drop of alcohol," he says.

"I'm clean and living the dream."

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