Perhaps consistent with its modest effects in COMBINE, naltrexone is not widely prescribed in the treatment of alcoholism. Yet, clinicians report that naltrexone may have significant benefits for individual patients. To make naltrexone a more useful medication, it would be important to begin to identify groups of patients who might be more or less likely to show a significant clinical benefit from naltrexone prescription and to understand the causes of differential naltrexone efficacy.
A new study that will appear in the September 15th issue of Biological Psychiatry suggests that alcohol dependent individuals with a family history of alcohol dependence may be more likely than alcohol dependent individuals without a family history of alcohol dependence to reduce their drinking in the laboratory when prescribed naltrexone.
Krishnan-Sarin and colleagues at the NIAAA Center for the Translational Neuroscience of Alcoholism studied alcohol consumption in the laboratory by alcohol-dependent individuals who were not seeking treatment.
The participants were studied in the laboratory after 6 days of treatment with 0 mg (placebo), 50 mg, or 100 mg of naltrexone. The authors discovered that naltrexone decreased drinking in those with a family history of alcoholism and this effect was greatest with the highest naltrexone dose. However, it increased drinking in those without a family history of alcoholism and this effect was greatest at the highest naltrexone dose.
John H. Krystal, M.D., one of the authors, notes that "When studied in large groups, naltrexone appears to have a rather small effect upon the ability to reduce drinking or remain abstinent from alcohol".
However, there is growing evidence that there are subgroups of patients who show substantial benefit from naltrexone, even when naltrexone fails to work in the overall trial (see Gueorguieva R et al. Biol Psychiatry. 2007 Jun 1;61(11):1290-5)."
According to Suchitra Krishnan-Sarin, Ph.D., the lead author, "The results suggest that family history of alcoholism may be an important predictor of clinical response to naltrexone and could potentially be used to guide clinical practice." Dr. Krystal agrees, "These data suggest that family history might influence the optimal dosing of naltrexone and the nature of the clinical response." Their hope is that these findings ultimately can contribute to a better treatment experience for some who are seeking to end their battle with alcohol.