drug used widely to treat alcoholism worked no better than sugar pills for long-term heavy drinkers, a new study finds. The study, to appear in The New England Journal of Medicine this week, examined the effects of the drug, naltrexone, with 600 veterans.

"Our data raise doubts about the current use of naltrexone for patients with chronic severe alcohol dependence," wrote the researchers, led by Dr. John H. Krystal of the Veterans Affairs Connecticut Health Care System.

The veterans, who averaged 49 years old and began drinking regularly in their 20's, reported that they drank about three days out of four and consumed an average of 13 drinks on the days when they drank.

Some of the veterans were given naltrexone for three months, others for a year. Still others took sugar pills with no medical effects.

In all three groups, the patients went an average of four and a half months without drinking. At 13 weeks and one year after the study began, they were drinking less and on far fewer days than they had when the study began. The reduction was about the same for all the groups.

Dr. Krystal said naltrexone might still prove effective for patients who drank less heavily or when combined with other drugs.

In an editorial accompanying the report, Dr. Richard K. Fuller and Dr. Enoch Gordis of the National Institute on Alcohol Abuse and Alcoholism noted that other studies had found naltrexone to be moderately effective and that the results of the new study might apply just to severe alcoholics.