By Simon Cox
Presenter, The Investigation: Heroin On The NHS
Earlier this week the first funeral took place of one of the five young women killed in Ipswich while working as prostitutes.
The Ipswich deaths raised concerns over links between sex and drugs
All had been supposedly working on the streets to help finance an addiction to heroin and crack cocaine.
Their deaths led to calls for heroin to be widely prescribed on the NHS as a way of stopping drug addicts becoming prostitutes.
On a cold night in Ipswich's red light district, Janine is working.
She is selling herself in order to buy drugs, specifically heroin and crack cocaine.
It's the same for all of the other prostitutes she knows. She says: "I can't name one girl who doesn't have a drug habit who works the streets."
Before the killings Janine was making almost £200 a night. All of it would be spent on drugs "apart from a phone credit and a packet of fags".
The heroin also helps her to do the work as, "it just numbs your emotions".
Her friend and fellow heroin user, Paula, the mother of a young baby, doesn't work as a prostitute but has watched many of her friends end up on the streets.
"I have seen girls do things for crack (cocaine) they would never dream of doing otherwise", she says.
Ten years ago Erin O'Mara, who lives in north west London, was in the same position as Janine.
To finance her habit she began working in the sex industry, initially as an escort. As her addiction developed she couldn't keep to any routine.
Many prostitutes work to get money to pay for drugs such as heroin
"When you have got a habit the drugs come first and if you don't have them by the time you start your shift you can't do it. That's why a lot of girls end up working on the street."
Erin no longer works as a prostitute but she does still take heroin. After 20 years on the drug she has tried every kind of treatment. Now she is part of a select group of drugs users who get their heroin on the NHS.
At a chemist near her flat there are several other addicts there collecting methadone prescriptions.
Methadone is synthetic heroin substitute and is the tried and trusted route for heroin addicts trying to kick the habit.
Erin is getting the real thing. The chemist is expecting her and hands over a bag containing her daily dose of pharmaceutical heroin. She has been doing this every few days, week in, week out, for the last four years.
She says: "You've got a measured dose, you know exactly how much you're taking and you can function perfectly well on it."
Her speech is a little slurred and she seems a little woozy but getting heroin on the NHS has given her stability - she now has a job and a flat.
"I felt like I was trapped on this treatment nightmare. Now that I get my heroin prescribed, all that anxiety has gone."
Erin is a special case. She is HIV positive and has had Hepatitis C so it's vital she doesn't share needles.
Currently just over 1% of heroin users in the UK, around 400 people, get their heroin in this way.
Each one costs the taxpayer around £10,000 a year.
In spite of this, some policy makers and police would like to see a lot more people being prescribed heroin.
Tom Lloyd, the recently retired Chief Constable of Cambridgeshire says heroin on the NHS could dramatically cut the cost of drug relate crime and improve the lives of heroin users.
"If they were allowed to have heroin under controlled circumstances then that chaos would be taken out of their lives, they could get their lives sorted out."
This is exactly what's currently happening in three areas in Britain where trials are being conducted into prescribing heroin on the NHS.
Users don't get it at their local chemist like Erin, but have to go to a centre to take the drug under strict supervision.
The trials have only been running for a year but Professor John Strang, director of the National Addiction Centre, says the early results are promising.
"Our strong clinical impression is we are seeing huge improvements which we would not ordinarily have seen."
The stiffest opposition to wide scale heroin prescribing comes from Professor Strang's own colleagues within the medical establishment.
Will suit 'a minority'
At his private GP practice in Felixstowe in Suffolk, Dr John McMurray has been dispensing methadone to heroin users for many years.
He says giving heroin to patients, even heavily addicted users like Erin O'Mara, could end up killing them.
"What you needed to feel perfectly OK yesterday if you use today could be sufficient to kill you".
Even those campaigning for heroin on the NHS say it will only be suitable for a minority of heroin users.
That could still mean up to 25,000 addicts being given free heroin. The bill for the NHS would be around £375m.
Dr Emily Finch is a consultant psychiatrist in addiction at the Maudsley Hospital, one of the sites conducting trials into heroin prescribing.
She says it won't be up to doctors to decide whether the scheme should be rolled out: "Society will have to think about whether they want this treatment to be available and whether they are prepared to pay for it."
The Investigation: Heroin On The NHS will be broadcast on Radio 4 at 2000 GMT on Thursday 8 February.
You can also listen online for 7 days after that at Radio 4's Listen again page.