Methadone (methadone hydrochloride) is the predominant MAT drug used inside and outside prisons. It is a synthetic opioid agonist that has an effect similar to that of morphine. Methadone is well absorbed from the gastrointestinal tract, irrespective of formulation type (syrup versus tablet). It has very good bioavailability of 80–95%. The estimated elimination half-life of methadone is 24–36 hours, with considerable variation across individuals (10 to 80 hours). This pharmaceutical profile makes methadone useful as a substitute opioid medication, because it allows oral administration, single daily dosage and achievement of steady-state plasma levels after repeated administration with no opioid withdrawal during an usual one-day dosing interval.
Some patients experience side effects. The most common side effects include increased perspiration, constipation and disturbances of sleep, reduced libido (sex drive) reduced power of concentration as well as a potential for weight gain. Such undesirable side effects generally occur at the beginning of treatment and ameliorate over time. In some patients these side effects persist over longer periods of treatment, but mostly remain without medical consequences. In total, these side effects affect less than 20% of patients taking methadone therapy.
Methadone is a safe medication with no lasting deleterious physical or physiological effects. Contrary to what is popularly assumed, it has no direct damaging effects on bones, teeth or organs (opioids do restrict saliva production, which in turn can lead to dental caries). However, for some patients, detoxifying from methadone might be very difficult and protracted.
Methadone is a cheap medication; it is easy to deliver to the prisoner and the intake can easily be supervised. In most of the cases, only little information is given to patients about the substitution drug. This might be due to the assumption of providers that everything about the medication is already known by experienced patients. However, this is not always the case.
The barest basics – a guide for providers
To the greatest extent permitted by local laws and regulations, methadone should be provided pursuant to the same professional and ethical standards that apply to all other health services. Providers should encourage the availability of a broad range of treatment approaches and sources of care and assist in referring and transferring drug users upon request.
The vast body of experience with the use of methadone in the treatment of opioid dependence should be utilised to the maximum. It is accessible through the professional literature, web-based resources or direct consultation with colleagues. Methadone maintenance – even when provided over a period of decades – is not associated with adverse effects on any organ of the body.
People’s lives can be chaotic at the start of treatment, which warrants a relatively greater degree of supervision and structure. Any constraints, however (such as on take-home medication), should be reviewed on an ongoing basis and relaxed or removed as stability is achieved.
General rule: start low, go slow – but aim high
First, do no harm: estimates of the degree of dependence and tolerance are unreliable and should never be the basis for starting doses of methadone that could, if the estimation is wrong, cause overdose.
- There is no moral value associated with either “high” or “low” doses,
- Methadone should not be given as “reward” or withheld as “punishment”.
- Dosages should be increased and decreased gradually. Both for safety and comfort, smaller changes (such as 5 mg at a time) at wider intervals (such as every five days) should be utilised when people are at relatively lower dosage levels (less than 60 mg per day), whereas larger and more frequent changes (such as 10 mg every three days) will generally be safe at higher levels.
- In general, higher maintenance doses are associated with better therapeutic outcomes than are lower doses; the range optimally effective for most people is 60–120 mg per day.
- When there are subjective complaints of “methadone not holding”, consider dividing – as well as increasing – the daily dose; this may be particularly relevant for people who are pregnant and/or receiving antiretroviral therapy.
- The more that can be offered the better, but such service should not be mandatory.
- One of the major obstacles to the effectiveness of methadone treatment is the widespread stigma associated with the condition of dependence, the person being treated and the treatment. Drug users should be supported in dealing with this stigma, and providers should seek every opportunity to educate the public (including, perhaps most importantly, health care colleagues).
Maintaining continuity of care
- To the greatest extent possible, arrangements to continue methadone should be made for people upon entering institutions (such as police detention, arrest house, hospital or prison) or returning from them to the community.
- Unless there is unequivocal documentation that higher doses of methadone were given in the previous setting, the dosage guidelines recommended for new drug users should be applied.
Urine toxicology and serum methadone levels
- The value of these and other laboratory tests must be weighed against their costs and the potential benefits of enhanced treatment services the funds could otherwise support. Clinical guidelines in many countries insist on a drug testing prior to the commencement of substitution treatment.
- Observing the act of urination is demeaning and usually antithetical to an optimal physician-patient relationship.
- Treatment goals might relate to heroin and other drug use, HIV risk behaviour, relationships, employment, housing, etc. – but they should be determined collaboratively by the clinician and drug user and generally not imposed by the treatment provider.
Informed consent – special considerations in addiction treatment
- The drug user must be informed at the start of treatment if the clinician’s primary obligation is to the state or some other third party – such as to a court, employer, family member, etc. Even if this is not the case, in many countries drug users will not believe that their confidentiality will be protected, and this view – whether justified or not – may affect the therapeutic relationship.
- The drug users must be advised of the specific causes for involuntary termination and the appeal mechanism(s) available to challenge such terminations. Drug users considering voluntary termination of treatment must be informed of the possibility of subsequent relapse. Users who have chosen voluntary termination should be encouraged to reduce dosages at their own pace rather than accept forced dose reduction intervals.
As mentioned above, findings have consistently demonstrated significant benefits associated with both methadone maintenance and, more recently, buprenorphine maintenance treatment.
In view of the high relative value of drugs in prison, it is recommended that all substitution agents are administered to patients in prison under supervised consumption conditions. The presence of a secondary responsible person, a nurse rather than a custodial officer, can serve to ensure that the medication is not diverted.