Is the Prescription of Amphetamine Justified as a Harm Reduction Measure?

Amphetamine is, after cannabis, the most widely illicitly used drug in the United Kingdom. Many indicators point to an increase in its availability and use during the 1980s (Institute for the Study of Drug Dependence 1993). For example, there was a doubling of the number of police amphetamine seizures between 1989 and 1991 (HomeOffice,1992). There have been a number of local and national surveys that have shown an increase in the use of amphetamine by young people (Institute for the Study of Drug Dependence,1993). During recent years amphetamine use has become part of the ‘dance drug’ phenomenon, the use of stimulant and hallucinogenic drugs on a recreational basis to enhance the experience of energetic dancing at clubs and parties (Newcombe,1992). There is no doubt that some of the increase in the use of amphetamine is accounted for by such occasional recreational use.

To what extent has there been an increase in problematic amphetamine use? Until the setting up of regional drug databases we have had little Information on the numbers of amphetamine misusers presenting to drug agencies. The data from these databases has shown an increase in reported amphetamine use. The North Western Region Database, the longest running in the UK, reported a 175% increase in amphetamine use between 1990 and 1992 with over 60% injecting (University of Manchester Drugs Research Unit, 1993). The same database reported an increase of 43% in the number of primary amphetamine users presenting to agencies between 1990 and 1992, of whom 41 % were injecting the drug (Wessex Region Drug Database, personal communication). Such information is likely to under-represent significantly the numbers of problematic amphetamine users as many drug services are oriented primarily to opiate users, and do not therefore attract amphetamine users (Klee, 1992a).

Our interest in amphetamine misusers in the Portsmouth area dates from the setting up of a pilot needle exchange scheme in the city in 1987. This was one of a number of such schemes funded bv the Department of Health and monitored by Stimson and his colleagues at Goldsmiths’ College, London. Unlike the experience at most of the other pilot schemes whose clients were opiate users, in Portsmouth the majority (67%) of those attending the needle exchange scheme were amphetamine misusers (Stimson et al, 1988). This was the first time that most of them had presented to any services. Many had a long history of injecting amphetamine and several of these led rather chaotic lives, sharing injecting equipment and having unsafe sex. One particular client, who was known to be HIV positive, frequently shared injecting equipment and had unprotected sex with several partners.

We were thus seeing, for the first time in most cases, individuals with major drug problems engaging in high risk behaviour, for whom we had nothing to offer beyond clean needles and syringes and advice on risk reduction. When asked why they had not been to the local drug service for help, most perceived the service as one for opiate users with nothing to offer amphetamine users. We thus began to consider how we might engage these amphetamine users in treatment and how we could help them reduce the risks they were exposing themselves to. We began to prescribe oral amphetamine to a few users with varying results. It became evident that we needed to develop clear criteria for such prescribing, have clear aims and improve our monitoring. It was following these deliberations that the amphetamine prescribing programme was set up.

The programme had the following aims:

1. To encourage amphetamine users into the service
2. To enable amphetamine users to reduce their injecting behaviour
3. To educate users about ways of reducing their high risk behaviour and thereby reduce the risk of spreading HIV and other infections
4. To reduce the risk from using adulterated street drugs, by providing pharmaceutical arnphetamine
5. To stabilise users’ lifestyles

The criteria for acceptance onto the programme included history of regular amphetamine misuse, with at least 6 months' daily injecting at the time of interview. There had to be evidence of recent injection sites and a supervised urine had to be positive for amphetamine. Subjects were excluded if there was an history of psychotic illness or other major psychiatric disorder. Finally, patients had to agree to abide by the conditions of the prograrnme.

The programme was located at a community based drug advice centre, where subjects were required to attend on 4 days a week. They received 30mg of dexamphetamine sulphate in suspension form taken, as liquid by mouth in front of staff. On the days they did not attend the centre they were given takeaway drugs and, if there was any doubt about their reliabiliry, arrangements could be made for them to consume their drugs at a retail pharmacist. On the days they attended the centre, after consuming the amphetamine, subjects were, required to join a group meeting whose aim was to promote motivation for change, and where practical advice on harm reduction was given. They were asked to note their injecting activity and fill this in on a form on a daily basis. Staff undertook: weekly monitoring of the injection sites for each patient. A monthly review of subjects’ physical and mental state was completed by one of the medical staff.

This paper reports the results of the operation of the amphetamine prescribing programme from its inception in April 1989 until June 1992.

METHOD

During the period of review a total of 18 men and 8 women were accepted onto the programme. 6 subjects (5 men and I woman) did not complete the questionnaire as they were uncontactable, this included 2 subjects who were in prison at the review date.

AT THE START OF THE PROGRAMME

At the time of the review subjects had been on the programme for a mean of 15 months, with a range of 0.25 - 42 months for the men, and 4—36 months for the women. Of the men 13 were still on the programme, 2 were in prison, 2 had been discharged for nor complying with the programme and 1 had left because he felt he could manage on his own. Of the women, 2 had come off amphetamine, 1 was in prison and the remaining 5 were still on the programme. Thus at the review date 67% of the subjects were still receiving, an amphetamine prescription.

INJECTING BEHAVIOUR

6 out of the 26 subjects (23%) were receiving prescriptions of methadone at the review date; all but 1 of these had received methadone since the start of the programme. Concerning illicit drug use, we have information on 20 out of 26 subjects. Only 2 subjects had reported not using any illicit drugs during the programme. The rest had all used amphetamine, 15 (83%) had injected the drug at some time during the programme. Cannabis was the next most often used drug taken by 11 out of the 18 subjects and cocaine had been used by 2.

CONDOM USE

Injecting amphetamine users are a high-risk group as far as HIV transmission is concerned. Klee, in an investigation into HIV related risk among injecting drug users in the north-west of England (Klee, 1992b) found that in the previous 6 months 56% of amphetamine users had used another’s equipment in that time compared with 44% of heroin injectors. Amphetamine users were more likely to report an increased interest in sex and were more likely to report having casual sexual contacts, than were heroin users. Half those who reported casual sex had shared their needles and syringes. It was our concern with the increased risks of HIV spread amongst this group that led to the establishing of the amphetamine programme.

There have been few reports of amphetamine prescribing as a measure to modify amphetamine users’ behaviour. Gardner and Connell (1972) reporting on amphetamine users seen in a drug dependence clinic in 1968/1969 commented that the prescription of amphetamine to this group was unlikely to be effective. Mitcheson et al (1976) described the treatment of 23 injecting methylamphetamine users at a London clinic in 1968. 12 of these were prescribed methylamphetamine arnpoules. Contact was difficult to maintain and in most cases outcome was poor. The general view has been that ‘it is undesirable to prescribe substitute stimulant drugs as the risk of them being misused is very high’ (Department of Health, 1991, p46). Nevertheless, a number of drug agencies in the United Kingdom have reported amphetamine prescribing on a limited basis, as a harm reduction measure (Standing Conference on Drug Abuse, 1989) Sherman in Australia reports on 14 methylamphetamine addicts who were treated with oral dexamphetamine (Sherman,1990).

Our experience of a closely supervised and monitored amphetamine prescribing programme has been that improvements in subjects’ behaviour can be demonstrated ‘ Over half the subjects had ceased injecting and in those still injecting there was reduction by a factor of 5 in the amount of injecting activity. There was a reduction in the sharing of injecting equipment. However, subjects reported still using street amphetamine and offending during the programme, although at a lower rate than previously.

One reason for the continued illicit use of amphetamine may have been that we were giving too low a dose of dexamphetamine. Our patients repeatedly told us that we should be prescribing larger doses. As with dosages of methadone in methadone maintenance programmes (Caplehorn et al, 1993), it may be that a higher dose of amphetamine would reduce the incidence of illicit drug use. Ourdosage of 30mg was reached on the assumption that the average amount of street amphetamine used each day was around one gram.. At an average purity level in 1989 of 7% (Home Office, 1992) this would mean 70mg of amphetamine. Street amphetamine is composed of the racemic form of amphetamine (Home Office, personal communication) of which only the d-form is active and thus 1 gram would contain approximately 35 mg of dexamphetamine. The amount of street amphetamine used on a daily basis by injecting users is probably rather greater than we had assumed, in part because of falling purity levels and this would explain why our doses were insufficient. We had been conservative in our dosage because we were concerned not to produce any paranoid symptomatology in our subjects. Regular mental state reviews did not disclose any abnormal mental states in our subjects, even though there must clearly have been times when they were taking much more amphetamine than we were prescribing.

How long should we continue prescribing for? At our review date 6756 of subjects were still receiving a prescription of amphetamine, having had one for a mean period of 15 months. This begins to look like an amphetamine maintenance programme. If such prescribing is producing benefits in terms of improved behaviour then why should it not continue on a longer term basis? This depends on what effects long term ingestion of amphetamine may have on an individual. Animal studies have shown that long term administration of amphetamine can cause depletion of noradrenaline and of 5-HT in the CNS (Gawin and Ellinwood,1970) and it has been suggested that some toxic effects may take a decade or more to become obvious. (Selden, 1991) The implications of these animal studies for treatment in the clinic are not yet clear but we need to be aware of the possibility of irreversible changes in the brain as a result of long term amphetamine ingestion. These effects might explain why some long term, high dose amphetamine users find it so difficult to come off their drugs. Equally we should be wary of recommending long term prescribing of arnphetamine until we are more knowledgeable about the long term effects.

One particular area of behaviour in which we found little change or improvement was that of sexual practices: the majority of our subjects stated they did not use condoms and only one subject had increased his use of condoms. Klee (1992b) noted in her study of the social and sexual lifestyles of amphetamine misusers that the prospects for behavioural change in this group was poor. For example 94% of those reporting casual sex in her study had a number of unprotected sexual episodes. This group of drug users need to be targeted for health promotion and this means being able to make contact with them and finding effective ways of altering their behaviour.

One effect of introducing an amphetamine prescribing programme has been to increase the number of primary amphetamine users presenting to che treatment services in our area (an increase of 75CEo between 1990 and 1992). These users were not necessarily looking for prescriptions of amphetamine but were often asking for help in either modifying, or ceasing their use of amphetamine. This has led us to look at other types of treatment, such as the use of desipramine (Tennant and Rawson, 1983) or fluoxetine (Polson 1993) to modify withdrawal symptoms. We have also had to consider whether there is a case for prescribing amphetamine to long term daily illicit users of the drug who are not injecting These are clearly dependent on amphetamine and although they may not be an at risk group as far as HIV spread is concerned, they may nevertheless have to commit offences to obtain the drug and their personal and social life may be thereby adversely affected by this dependence. If they are unwilling or unable to stop using amphetamine substitute prescribing could be a harm reduction intervention.

What conclusions can we draw from our experience? We have achieved some of the aims we set ourselves: we have encouraged more amphetamine users into the service; subjects’ injecting activity has been reduced and their lifestyles have become more stable. However, there was continued, though reduced, use of illicit amphetamine and there was little change in sexual practices. We have modified the programme for new patients to take into account some of our findings. It is now a time-limited prescribing programme of 14 months. For those patients who are motivated to make changes we have a ceiling of 60mg of dexamphetamine for a short period and more intensive and focused group therapy.

In summary, we believe that prescribing amphetamine in a closely controlled and monitored way to this group of injecting amphetamine users can be justified on harm minimisation grounds. However, there is an urgent need for more research in this neglected area (Klee,1992a), including controlled studies of amphetamine substitution.

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