A leading drugs expert says cannabis addicts are being let down because there is too much focus on helping people hooked on Class A substances.

Doctor Adam Winstock, founder of the Global Drug Survey, the world's biggest drug poll, told Newsbeat cannabis can be as tough to give up as heroin.

"We haven't invested enough in helping people who use cannabis use more safely - or stop," he said.

But health officials say there are properly funded services out there.

Dr Winstock said in the last 20 years services have focused too heavily on treating heroin and crack cocaine addicts "because they're the people the government sees as causing crime and disruption".

"I don't think people with problems with cannabis have easy access to services," he explained.

Cannabis use is falling across the UK but the number of people getting help with addiction is rising.

Experts say this is because cannabis is getting stronger and users are more likely to admit they have a problem with it.

In 2005 the number of 18 to 24-year-olds in England coming forward for treatment was 3,328. In 2013/14 that figure had risen to 4,997 and now accounts for nearly half of all new cases.

Cannabis Facts Cannabis is a Class B drug - it's illegal to possess, give away or sell



Possession is illegal whatever you're using it for, including pain relief



The penalty for possession is up to five years in prison



Supplying can get you up to 14 years and an unlimited fine



Giving it to friends, even if they don't pay, is considered as supplying

'My brain said no but my hands kept rolling'

Newsbeat gained exclusive access to Marijuana Anonymous (MA), a group which helps addicts.

We met one 25-year-old, "John", who explained how addiction took over his life.

"I would sit willing myself not to smoke even as I rolled a joint. My brain said no but my hands kept rolling and smoking.

"The drug wasn't making me happy, the weed was the cause and I couldn't stop. I couldn't stop.

"I have a hole inside me that I tried to fill. Weed fit the hole.

"It was the perfect match, it filled all the gaps and that's why I went back to it. Now I fill that with MA."

'50 to 60% have serious withdrawal'

Dr Winstock told Newsbeat that 50% to 60% of dependent users have serious withdrawal symptoms when they come off the substance.

"Some people become violent, some young people can't sleep and get very irritable".

Many claim that cannabis is different to other drugs and isn't physically addictive like heroin or cocaine.

Dr Winstock told us that argument misses the point.

"I think people get confused with physical withdrawal symptoms and equating those to being addicted.

"Addiction for me is a loss of control and when you stop you feel uncomfortable.

"[It] could be you feel miserable, you can't sleep, you lose your appetite or it can be very physical as it is with heroin or alcohol".

He said the younger the user the more likely they are to have problems in the future.

"About 10% of people who use cannabis are dependent and two-thirds of those people, when they stop, will experience withdrawal symptoms.

"They last seven to 10 days for most people. You are more likely to run into those problems if you start using early."

'I didn't wash. I could never put down weed'

23-year-old Lee got help from MA but before that he says his life was a blur of "joint after joint".

"Cannabis was my drug of no choice," he said.

"I found myself smoking even though I didn't want to be doing it. Physically it drained me, it made me very unhealthy. I was a broken man.

"I wasn't eating and I was just over five-and-a-half stone. Eating got in the way of my smoking.

"And I would go a week without having a bath or shower.

"I would smoke before work, during work, after work, I would lie to people just so I could be on my own smoking."

'I want to stop, but I am going to hang out with my friends'

Cases like Lee's make up most of the workload for drug workers like Phoebe Crowder from the charity Addaction, who works with young addicts in east London.

She told Newsbeat: "I have some young people saying 'I want to stop, but I am going to hang out with my friends. I have to physically not see my friends because I know they are going to smoke cannabis'.

"For some young people they feel it is around them all the time and that can be one of the biggest hurdles for someone looking to quit".

There are lots of departments responsible for drug addiction services across the UK. Scotland, Wales and Northern Ireland and England have separate systems.

Public Health England says waiting times are low for people looking for help with addiction,

A spokeswoman said: "Young people moving from young to adult services can be a really difficult transition; however services should be sensitive to the age and needs of the people they're working with and have the right arrangements in place to accommodate these."

Cannabis is a class B drug and carries a maximum prison sentence of five years for possession and up to 14 years for supply and production. You can also receive an unlimited fine for possession, supply or production.

Get help and information about drugs on the BBC Advice pages

And for more friendly, confidential drugs advice you can talk to Frank

Follow @BBCNewsbeat on Twitter, BBCNewsbeat on Instagram and Radio1Newsbeat on YouTube