The objective of this study was to conduct a pilot study of naltrexone
in opiate-dependent patients in order to determine the sample size fo
r a double-blind controlled trial, to identify possible confounders an
d to obtain experience with the drug's side effects and acceptability
to patients, Opiate-dependent patients presenting to a public hospital
for treatment for their dependence were invited to participate. Patie
nts with major organic illness, another Axis I diagnosis, or who were
pregnant were excluded. Naltrexone was prescribed at a dose of 50 mg d
aily for 6 months. Data were collected on drug use, social stability,
physical and mental health before during and after the treatment progr
amme. Patients were seen weekly for 6 months then monthly for a furthe
r 6 months, Forty-four patients were enrolled, but three stopped naltr
exone early because of possible side effects. Of the remainder, 32 wer
e followed for at least 12 months. Eight (25%) ceased opiate use from
the start, and another two were no longer using at the end of 12 month
s giving an abstinence rate of 31% at 12 months. Retention in treatmen
t was 34%, Of the abstinent patients however, only two took naltrexone
for the whole 6 months. Naltrexone was well tolerated and associated
with a significant abstinence rate, but most patients do not feel they
need to take the drug for 6 months. A double-blind controlled trial w
ould be justified.