To the Editor: The study by Dr Garbutt and
colleagues1 demonstrates that the use of injectable
naltrexone reduces the number of heavy drinking days in alcohol-dependent
individuals. An important limitation in these results is that despite the
long duration of the trial, the number of heavy drinking days per month did
not progressively decrease over time, suggesting that longer treatment would
be of no additional benefit. This is not surprising since craving, which is
the strongest predictor of subsequent drinking and relapse,2 has
never been reported to be completely eliminated by naltrexone. Reduction of
heavy drinking days has been previously established in randomized trials with
the oral administration of the craving-reducing agents naltrexone,3 topiramate,4 and low-dose
baclofen,5 and in an open-label trial of acamprosate.6