Heroin is a semi-synthetic opiate derived from morphine. It is produced in minimal
amounts legally and street heroin is produced in illicit laboratories. The chemical is a
white crystalline powder, soluble in water. Coloured preparations reflect different
contaminants present.
The drug is most commonly administered by injection (IV or IM) but it is also active if
smoked. While the drug can be used orally it is more often used parenterally because this
is a far more cost effective means of achieving the desired psychoactive effects.
The onset of action is rapid and the duration of action is approximately 3-4 hours. The
immediate effect or 'rush' after an IV dose is related to the high fat solubility of the
drug and thus its rapid entry into the brain.
As heroin is not legally available in Australia, illegal users obtain supplies of the
drug on the street. This results in the dosage being:
- of variable amount; and
- contaminated by a variety of diluents of varying quality and safety.
Most users inject their dose using a number of solvents for the powder they purchase.
Acidifying agents are used to facilitate dissolving the drug and these in their own right
may produce complications (eg fungal contamination of lemon juice). Users inject
intermittently and may pass from recreational use (1 x week or less) to a major habit
where doses costing up to $1000 day are used in 3-4 injections.
It is apparent that treating an individual who shoots up four times a day with heroin
would prove very difficult if each dose had to be supervised. Many illicit users are
unable to obtain regular doses every day and will substitute heroin with other CNS
depressants, typically benzodiazepines.
Management of heroin dependence is complex. A number of alternatives are available to
those who are opioid-dependent. Treatment options include methadone substitution,
detoxification in a hospital or approved detoxification centre, supervised outpatient
detoxification, drug-free therapeutic community programs, rehabilitation in a residential
centre, individual or family counselling and self-help groups.
While drug-free treatments attract fewer patients than methadone maintenance, have
lower rates of retention in treatment, and lower rates of successful graduation to a
sustained drug-free lifestyle, they have been shown to be effective in reducing the
frequency of injecting drug use. The natural history of opiate dependence indicates that
many do grow through their period of dependence irrespective of treatments offered. Each
approach aids some patients but by no means all.
The morbidity of heroin users is significantly higher than that of their non-drug using
peers. This reflects the severity of many of the complications they experience, including
those related to their drug-seeking lifestyle, eg nutritional deficits, violence.
Methadone has been employed in the management of heroin users for over 20 years, but
despite this many arguments continue to rage regarding the place of this treatment
approach.
Methadone, a synthetic opiate, replaces heroin and in doing so decreases the need for
heroin-dependent individuals to regularly use the intravenous opiate. As methadone has a
longer life in the body than heroin, clients participating in a methadone maintenance
program receive a single prescribed dose of methadone every day. The dose is determined
according to the characteristics of the individual. The amount of methadone prescribed is
enough to eliminate withdrawal symptoms for 24-36 hours, while still allowing the
individual to undertake normal activities and functions.
The client must take the prescribed dose every day to ensure a stable level of
methadone in the bloodstream and control any physical effects which may be experienced.
The effects of the drug will vary from person to person. While some individuals will not
experience any adverse effects, the strength of effects and their duration may depend upon
the size of the dose and the frequency of administration.
Methadone, when administered in pure and regular doses as part of a treatment program,
should not have any severe long-term effects on an individual's health.
Possible long-term effects:
- weight increase, usually due to fluid retention or change in diet
- tooth decay, due to reduction in amount of saliva produced (is often present prior to
participation in methadone program)
- may lead to impotence or delayed ejaculation in some men
- loss of libido has been reported by some women
- amenorrhoea
- disrupted menstrual cycles
- reduced fertility
- methadone can be particularly harmful to people with kidney and liver diseases.
These effects are often emphasised by the opiate-dependent and their suppliers to avoid
treatment.
MIXING DRUGS CAN BE DANGEROUS
Using other drugs with methadone can be dangerous. This includes alcohol,
tranquillisers and cannabis. While some drugs reduce or change the effects of methadone,
methadone itself can alter the effectiveness of other drugs, or produce unexpected side
effects.
It is very important that people inform their doctor or dentist of their participation
in a methadone maintenance program to ensure that they are not prescribed anything which
could affect the treatment, and so that other medical procedures (eg administration of
anaesthetics) are safe.
In establishing an effective methadone program, it is appropriate to have a clear view
of what the methadone is being used for. Guidelines for achieving success should include:
- establishing the goals and objectives of the program
- educating staff on the goals and objectives and reasons for them
- providing information to patients on the goals of the program
- establishing a working system directed to achieving the goals
- adhering to unit policy.
This list does not suggest that policies may vary from unit to unit and this is indeed
the case. Perhaps the most common use of methadone is in the form of a long-term
maintenance program in which patients receive a once-daily doses of methadone over a
period of months or, in many cases, years. Urine testing is carried out in almost all
programs and it is appropriate for patients to be challenged if heroin use continues.
Exactly what steps should be taken in a patient who persistently uses heroin remains
debatable. The approval of a State health authority is required both for doctors to
prescribe methadone and for a drug-dependent person to receive it.
Methadone maintenance is a complicated treatment for a complex group of patients.
Individuals should not embark on such programs without very clear guidelines and without
links to a major unit that can provide support should difficulties arise.
The Human Immunodeficiency Virus (HIV) has three main modes of transmission. It can be
transmitted through the exchange of HIV-infected body fluids during unprotected sex;
through the use of HIV-contaminated injecting equipment; and may be passed on from mother
to child during pregnancy or birth, and possibly via breast milk during feeding.
Injecting drug users are potentially at risk for transmission of HIV through sexual
contact or use of non-sterile injecting equipment. As there is no cure for HIV/AIDS, the
only way to curb its rapid spread is by eliminating or modifying the risk behaviours
involved in its transmission.
For injecting drug users changes may include abstinence, or if this is not feasible,
either changing the route of administration of the drug (eg oral ingestion or smoking), or
undertaking safer injecting practices, namely, not sharing injecting equipment or, if
sharing, properly cleaning the equipment by either sterilising or rinsing with bleach.
Medical practitioners and other health workers to should alert injecting drug users to
the risks of HIV transmission and provide them with information about safe sexual and
injecting behaviour. Appropriate information may include:
- warning about the risks of needle sharing
- needle and syringe cleaning techniques
- the availability of clean needles and syringes or needle exchange programs in the area
- safer sexual practices
- the availability of free condoms.
New users and irregular users are also a group which are at high risk of contracting
the HIV infection through the use of contaminated injecting equipment. For new users this
occurs because they are usually initiated with the use of an experienced user's injecting
equipment, while for irregular users their drug use is often unplanned and thus they may
share needles because they do not possess the necessary equipment.
Methadone maintenance programs have been found to be effective in reducing the
frequency of injecting and the incidence of needle sharing. They are also effective
dissemination points for information about HIV/AIDS, and for users who may be infected
with HIV they provide vital contact with the health system.
