Gene Could Sway Response to Anti-Alcoholism Drug

MONDAY, July 24, 2006 (HealthDay News) -- Naltrexone, a drug used to treat alcoholism, may work better in some people than others, depending on whether or not they carry a certain gene.

People who carry a specific variant of the OPRM1 gene may actually have a greater urge to drink when they take naltrexone (NTX), concluded a U.S. study in the August issue of the journal Alcoholism: Clinical & Experimental Research.

"We know that NTX does not work for all alcohol-dependent people who take it," John McGeary, a research psychologist at the Providence VA Medical Center, said in a prepared statement.

"Some evidence suggests that alcoholics who have a positive family history -- other alcoholics in their family -- may have a better response to NTX. This can suggest genetic factors, environmental factors, or both. The finding that family history might be related to NTX response gave us the idea to examine specific genes that might account for this effect," McGeary said.

Working with colleagues at the Medical University of South Carolina, McGeary analyzed data from 90 people, all heavy drinkers, who took part in a larger study that examined how NTX affected the urge to drink and drinking.

They found that the OPRM1 gene had different moderating effects on NTX's impact. The researchers were surprised to find that people with a specific variant of the OPRM1 gene had a greater urge to drink when they took NTX.

"These findings challenge the notion that NTX works by reducing craving and suggest that there may be another mechanism of action for NTX. Furthermore, we may have identified a genetic variation that predicts response to NTX," McGeary said.

More information

The American Medical Association has more about alcoholism.