Comparisons from UK, Victoria and NSW.

Comparisons from UK, Victoria and NSW. Drug dilution, crushing, take-aways: the practice versus the evidence. February 05, 2008

Presenter: Dr Nicholas Lintzeris.

Dear Colleagues,
Dr Lintzeris began by describing his shock at the state of skin and veins in a large proportion of drug users in England when he started a sabbatical session at the National Addiction Centre and Maudsley Hospital in 2003. He showed some unflattering photographs of lower limb ‘war-wounds’ inflicted by hypodermic needles, infections, impure brown heroin and neglect. Most of these people had ‘worked through’ their upper limb then moving to the legs so that 20 to 50% of patients in maintenance treatments were using their groin veins for access.

The street heroin used was of the Afghan or ‘brown‘ variety, needing lemon juice or acetic acid to make it soluble. Even then it was still caustic to the veins. Dr Lintzeris noted that there were very high rates of crack cocaine use in English patients, up to 40% smoking it regularly whilst in treatment. He quoted the mental and physical toll this took on the lives of addicts and their families. Alcohol and sedative use was also common. Notably, one common drug of abuse was amitriptyline (‘Tryptanol’, ‘Endep’), an antidepressant not known for recreational use in Australia.

Balancing the intravenous damage to some extent (and perhaps because of it) there was a high proportion of drug users who did not inject at all. Up to 40% were smoking, snorting or swallowing their drug of choice at the time of entering treatment. In Australia about 90% of addicts entering treatment are injectors.

Dr Linzeris noted two main differences in maintenance therapies. Dose levels were generally in the low range (30-50mg daily) and the medication was usually given as “take away” bottles of weak solution rather than being taken under supervision. The use of 1mg per 1ml solution had parallels with the common practice in Victoria of ‘topping up’ take-away bottles with up to 100ml of water or cordial to discourage injecting.

Some graphs were shown of methadone treatment in Victoria from 1985 when there were only about 100 patients in treatment. By 1996 there were nearly 4000, and by 2003 about 8000 patients on maintenance treatments. An early experience of 10 deaths in patients starting methadone has shaped the Victorian approach to treatment ever since (see Drummer 1990). Mean dose levels in Victoria have always been in the low range, around 40mg, and only reaching 50mg daily in recent years (NSW is around 70mg). We were told that there were essentially no public clinics in Melbourne and nearly all patients were treated in pharmacies from GP prescribers. This means no capacity for subsidised methadone treatment since all patients must pay for pharmacy dispensing which is normally from 3-5 dollars daily. Very few take-away doses were permitted (originally 3 single doses per month) although this is changing now under more flexible health department rules.

Next we were informed that 33% of 193 authorised prescribers had no active patients. Another 33% had from 1 to 10 patients only while just 15% of the busier prescribers were treating 69% of Victoria’s patients. Thus most of the dependency treatment service in Victoria relies on just 27 individual doctors! By contrast in 2005 NSW had over 500 prescribers and 16,000 patients with no one doctor prescribing for more than 150 patients. In England all doctors can prescribe methadone if they wish to.

Buprenorphine has had significantly greater uptake in Victoria than in the other states. After the first year of use (Jan 2002) there was just 10% of the total on buprenorphine according to some bar charts we were shown. By 2004 it rose to over 50% briefly and then dropped back slightly to 40:60 bup:meth since that time. One may speculate on the reasons, but they probably include the rigidity of the original methadone regulations in Victoria. There was widespread use of second daily buprenorphine even though this is not shown to be as effective as daily use.

In Victoria even the more complex patients with extensive needs and poor resources were still mostly managed by GPs and pharmacists as there are no comprehensive clinics with access to counsellors, psychology, vocational support, social work, etc. Dr Lintzeris called this the ‘minimalist’ model. On the other hand, he told us that considering the state of play in Great Britain, there was simply no model or ‘system’ at all! This was not quite fair since he then showed a pie chart demonstrating that one quarter of patients in GP prescribing (nearly all ‘NHS’), another quarter in ‘shared care’ between formal clinics and GPs with fully 50% of all patients now in formal ‘specialist programs’ (Community Drug Teams). While some of these latter can formally supervise doses, few pharmacies give witnessed doses.

Treatment access across the UK was highly variable and depended on GP willingness to prescribe. Waiting times for GPs is usually about 2 weeks but up to 3 months for Community Drug Team assessments. Proper, evidence based maintenance treatment (as per UK treatment guidelines) is the exception with most patients on low and reducing doses with sadly predictable results. A common practice is for 40mg daily to start with and reductions from there.

GPs in the UK also commonly prescribe codeine, dihydrocodeine and buprenorphine but more due to personal preference rather than patient need. This applies equally to injectable methadone which comprised 10% of all opioid treatment prescriptions 10 years ago but is less than that now, partly due to the 1999 “Orange” guidelines which were sent to every practising GP in the UK. Methadone tablets are also less used now with about 95% of maintenance medication being methadone in liquid form, mostly the watery and bulky 1mg/1ml solution. Injecting of methadone is rare, as in Victoria, presumably due to dilution of doses which is almost universal. Whether such measures have more benefits than drawbacks on balance has never been tested scientifically. Thus it would seem prudent to consider diluting (‘expanding’) doses in special cases but not ‘across the board’ until such evidence is presented.

Another disadvantage of non-supervised consumption in the UK is that the ‘black-market is flooded’. There is now a scheme whereby pharmacists are paid 1 to 2 pounds daily to administer doses of methadone; patients usually pay nothing. Over a third of patients attend once weekly (6 or 7 bottles dispensed) with a third attending daily (except Sunday) often taking a bottle home. Most of the reminder attend 2, 3 or 4 times weekly. There are no hard and fast rules to addiction treatment in the UK allowing much more professional freedom. Whether that is a good thing overall is a moot point considering the poor adherence to good prescribing practice over many years.

The scientific evidence shows that if take-away doses and less supervision were linked to demonstrated progress, such as urine test results, this was the most effective intervention as ‘contingency management’ by another name.

Dr Lintzeris mentioned the various risks of injecting methadone, overdoses, child deaths and the public perception of the drug treatment system generally. We were told that people could successfully inject the buprenorphine combination drug with naloxone, Suboxone (unpublished comparative study by Leslie Amass, CPDD 2000). Also Dr Lintzeris quoted reductions in the injecting of methadone in NSW and said that the reason behind this was not clear.

Crushing of buprenorphine tablets has been advised by some parties yet evidence is limited on the practice. It would seem logical in some patients who had been caught diverting tablets, yet it clearly will not solve all the problems of buprenorphine administration.

This returned us to some questions posed by Dr Hallinan before the seminar: Why do we have public clinics, private clinics and pharmacy dosing for supervised treatment in NSW? Along with prison programs, is this serendipitously world's best practice, or a ‘clumsy and vestigial hybrid’? Are we using a number of flexible treatment models for people in various circumstances, or limiting access to opioid maintenance treatments which could be given more effectively in another way? Later discussion and case studies dealt with issues surrounding "access block" in NSW.

Summary by Andrew Byrne based on Dr Lintzeris’ power point presentation, questions on the night and some comments from Dr Richard Hallinan.