In the New England Journal of Medicine for November 2, Patrick O'Connor of Yale summarises the current opportunities which have arisen for treating dependence on opioid drugs, in the light of an increasing abuse of diamorphine.
The two main approaches to the problem, writes O'Connor, are opioid detoxification and maintenance therapy using an opioid agonist. Detoxification itself can be achieved by treatment with methadone in conjunction with clonidine, but this does not remain effective for longer than a few days or weeks, and needs to be followed by treatment with a longer acting opioid agonist accompanied by counselling.
The mainstay of maintenance treatment in the past has been methadone. Today, levomethadyl acetate and buprenorphine have proved highly effective, and preferable since they are relatively long acting. Levomethadyl acetate can be administered three times weekly instead of daily as with methadone. An optimal dose is necessary, and underdosage retards progress.
Buprenorphine, being a partial opioid agonist, may have an advantage over both methadone and levomethadyl acetate. It causes fewer withdrawal symptoms and carries a lesser risk of overdosage. When given in adequate doses it has an effectiveness equal to that of methadone and requires administration only three times weekly. In the United States, some trials are under way in which an orally administered formulation of buprenorphine with naloxone is used.
The unduly extensive and close regulation of treatment for opioid dependence is believed to detract from the efficacy of treatment schedules in general, in diminishing the high incidence of abuse. The ability to undertake maintenance treatment by physicians in their own consulting rooms would probably increase the benefits achieved.