B2 Prescriptions
Key Points 2006/07
Overview
Methadone hydrochloride (methadone mixture) is the most commonly
used pharmacological treatment for opioid dependency in Scotland.
It is used primarily for the treatment of drug addiction. Tables
B2.1 and B2.2 list other drugs which are sometimes used for the
treatment of opioid dependence. Some of these are also commonly
prescribed for non-drug misusing patients. It is not possible to
assess what proportion of these prescriptions were for the purposes
of treating drug dependence.
- In Scotland in 2006/07 there were 489,447 prescriptions for
methadone mixture, around 96 prescriptions per 1,000 population
(Table B2.3).
- The cost of dispensing methadone mixture (dispensing fees and
ingredients) for Scotland in 2006/07 was £12,683,660
around £2,479 per 1,000 population (Table B2.4).
- Diazepam, dihydrocodeine and temazepam were prescribed at,
respectively, rates of 163, 85 and 72 prescriptions per 1,000
population in 2006/07. Buprenorphine was prescribed at a rate of 9
prescriptions per 1,000 population (Table B2.1).
- In 2006/07 87% of methadone prescriptions in Scotland were
dispensed in instalments (Table B2.5).
Five year trends - 2002/2003 to 2006/07
- The cost of methadone mixture prescriptions has seen an overall
increase of 17% between 2002/03 and 2006/07
(£10,855,585 rising to £12,683,660).
However, the highest cost over the period was in 2004/05
(£12,935,828). It then fell in 2005/06 to
£12,200,215 before rising again in 2006/07 (Table
B2.4).
- Methadone prescribing rates have risen by 35% over the last
five years, from 71 per 1,000 population in 2002/03 to 96 per 1,000
population in 2006/07 (Table B2.2).
- The rate of prescribing of dihydrocodeine has remained
relatively stable between 2002/03 and 2006/07. The rate of
prescribing of buprenorphine has increased from 2 to 9
prescriptions per 1,000 population between 2002/03 and 2006/07.
Diazepam prescribing rates rose by 9% between 2002/03 and 2005/06
(150 to 163 prescriptions per 1,000 population). The only decrease
over the time period was in temazepam prescribing which fell by 16%
from 86 to 72 prescriptions per 1,000 population (Table B2.2).
Geographical profile
- Methadone prescription rates vary across Scotland from 180 per
1,000 population in NHS Ayrshire and Arran to 16 per 1,000
population in NHS Borders (Table B2.1).
- NHS Tayside is the only area which has seen a decrease in the
rate of methadone mixture prescribing between 2002/03 and 2006/07,
from 56 to 38 prescriptions per 1,000 population. The rate
increased in all other areas (Table B2.3).
- The cost of methadone mixture fees and ingredients per 1,000
population varies across Scotland. The cost was highest in Ayrshire
and Arran (£4,121 per 1,000 population), Greater
Glasgow and Clyde (£3,927 per 1,000 population) and
Lothian (£3,480 per 1,000 population) (Table
B2.4).
- The percentage of methadone mixture prescriptions dispensed in
instalments varied across Scotland. It was highest in NHS Greater
Glasgow and Clyde and NHS Shetland with 91% of prescriptions
dispensed by instalment. It was lowest in Orkney where only 47% of
methadone mixture prescriptions were dispensed by instalment (Table
B2.5).
Background information
Prescribed medication can be used for the treatment of drug
addiction. Methadone hydrochloride (methadone mixture) is a
commonly used pharmacological treatment for opioid dependence.
Methadone mixture for the treatment of opioid dependence comprises
the majority of methadone prescribing. Other formulations of
methadone are used in the treatment of severe pain and palliative
care.
There is no national routine information which reports the
number of people in Scotland who are receiving methadone
hydrochloride mixture, nor information on the cost per person to
the NHS. The Prescribing Information System (PIS) at ISD Scotland
holds information derived from prescriptions dispensed in the
community in Scotland. The system and information held constitute a
key part of the pharmacy payment process. However, the PIS does not
store patient identifiable information (e.g. name, date of birth,
address) that can be used to count the number of people receiving
particular medications.
Temazepam and Diazepam are prescribed to sedate, induce sleep,
and relieve severe anxiety as well as a substitute medication for
problem drug users. Dihydrocodeine and Buprenorphine are used for
the relief of moderate to severe pain and also for the management
of opiate dependence. Some of these drugs are commonly prescribed
for non-drug using patients and so is not possible to assess
precisely what proportion of these prescriptions is for the
treatment of drug dependence.
Defined Daily Doses
Defined Daily Doses (DDDs) cited in the following data are
considered to be a more accurate index of prescribing volume than
the number of items prescribed alone. A DDD is defined by the World
Health Organisation (WHO) as the typical adult daily maintenance
dose of a drug1.
Although DDDs are considered to be superior to number of items
as a unit of comparative analysis, difficulties may arise when they
are used in estimating disease prevalence, because they correspond
to a drug's principal indication2.
Defined Daily Doses used in the production of the following data
are based on the WHO Definitions:
Methadone mixture 25mg; insofar as methadone mixture is
concerned, it is useful to bear in mind that Department of Health
Guidelines (1999)3 suggest that while 25-40 mg of
methadone mixture is an appropriate initial daily dosage (during
assessment), the stabilization dosage offered on a longer term
basis should be 60-100 mg/day.
Dihydrocodeine 120mg;
Buprenorphine 1.2mg;
Diazepam 10mg;
Temazepam 20mg.
Instalment dispensing
Single dispensing occurs where the whole of an item is dispensed
on one occasion (e.g. multiple doses are dispensed and taken home
by patient). Instalment dispensing occurs where a proportion of the
prescription item is dispensed on multiple occasions (e.g. a single
daily dose is dispensed each day for seven days).
Where items are dispensed in instalments, the number of
dispensings exceeds the number of items, but where items are
dispensed singly, the number of dispensings will equal the number
of items. For many instalment prescriptions the quantity per
dispensing is equivalent to the daily dose of methadone requested.
However, it should be noted that for a significant proportion of
prescription items, there will be a discrepancy between the
prescribed daily dose and the amount dispensed by instalment. This
is because pharmacies often dispense a double dose of methadone
mixture on Saturdays, to cover Sunday’s instalment;
additional doses will also be added to an instalment to cover
public holidays.
References
1 -World Health Organisation (WHO) (1991). Guidelines for
defined daily doses. WHO Collaborating for Drug Statistics
Methodology. Oslo.
2 -Frischer M, Chapman S (1998). Issues and directions in
prescribing analysis. In: Medicines Management. Eds. Panton R,
Chapman S. 82-84 BMJ and Ph.Press. London.
3 --Department of Health (1999). Drug misuse and dependence
– guidelines on clinical management. The Scottish Office
Department of Health, the Welsh Office and the Department of Health
and Social Services, Northern Ireland. London: Stationery
Office.
Further information
Although there is no routine information on the number of people
receiving a methadone prescription, ISD Scotland has published a
paper providing estimates of the number of people receiving a
methadone prescription. This paper was published in 2005 and is
available at http://www.drugmisuse.isdscotland.org/publications/abstracts/isd_methadone.htm
The Prescribing Information System (PIS) holds information on a
variety of different medications prescribed in Scotland.
Information on the data and statistics are available at http://www.isdscotland.org/prescribing
If you would like further information on methadone prescriptions
or on prescriptions of other medications related to drug misuse
please contact the Substance Misuse Information Strategy Team at substancemisuse@isd.csa.scot.nhs.uk.
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