Benzodiazepines effective against alcohol withdrawal seizures

(2005-09-04)

Tranquilizers work better than placebos at treating the symptoms of alcohol withdrawal syndrome but they may not work better than other drugs, according to a new review of recent studies.

The class of depressant drugs known as benzodiazepines are especially effective at treating seizure in withdrawal patients, say Dr. Christos Ntais of the University of Ioannina School of Medicine in Greece and colleagues. People given benzodiazepines were 84 percent less likely to have withdrawal-related seizures compared to those given placebos.

"This might suggest that their [benzodiazepines'] current status as first-line treatment for alcohol withdrawal syndrome is justified," Ntais and colleagues say.

However, the researchers found no evidence that benzodiazepines are any better than other drugs used for treating alcohol withdrawal syndrome or that there are any differences between types of benzodiazepines for withdrawal treatment.

"There was no conclusive evidence or even hints for superiority of specific drugs, but modest differences could have been missed due to limited data," Ntais says.

Among the commonly known benzodiazepines are Halcion, Versed, Librium, Xanax and Valium.

In a second review, Dr. Anastasia Polycarpou, also of the University of Ioannina School of Medicine, and colleagues found some evidence that anticonvulsant drugs such as carbamazepine (Epitol or Tegretol, for example) are more effective than placebo at treating alcohol withdrawal, but the difference was not statistically significant.

The reviews appear in the current issue of The Cochrane Library, a publication of The Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic.

Alcoholics can go through withdrawal when they stop or cut back on their drinking. Symptoms of withdrawal can include everything from insomnia, sweating and rapid heart beat to nausea, seizures and hallucinations. The most severe form of withdrawal syndrome is called delirium tremens.

Alcohol addiction affects certain neurotransmitter circuits in the brain, and the symptoms of alcohol withdrawal reflect the brain's attempt to readjust those circuits. Benzodiazepines act on one particular type of circuit called GABA pathways.

Ntais and colleagues examined 57 studies of benzodiazepine treatment for 4,051 people. Polycarpou and colleagues analyzed 48 studies of anticonvulsant treatment for 3,610 people. Although the number of studies is relatively high for systematic reviews, the studies had a large variety of outcomes and measurements that made it difficult to combine and analyze the data as a whole, according to both review teams.

Although not all of the studies reported side effects from the drugs, deaths and serious complications from the treatments appear to be rare, the reviewers say.

"The extremely small mortality rate in all these studies is reassuring, but data on other harms-related outcomes are sparse and fragmented," Ntais says.

Sarah Book, a professor at the Medical University of South Carolina who has studied the effects of both benzodiazepines and anticonvulsants for alcohol withdrawal, says there may be other reasons to be cautious about benzodiazepine treatment.

"In general, benzodiazepines have the potential to increase the risk of [alcoholic] relapse," Book says.

Book also says "the combination of alcohol and benzodiazepines can be deadly," a problem that does not occur with anticonvulsants, she adds.

According to Book, the majority of benzodiazepine prescriptions for withdrawal are made on an outpatient basis, with little opportunity to monitor a patient's continued drinking.

The Cochrane reviews were supported by the European Community, Directorate of Public Health.

By Becky Ham, Science Writer
Health Behavior News Service

FOR MORE INFORMATION
Health Behavior News Service: (202) 387-2829 or http://www.hbns.org.

Ntais C, Pakos E, Kyzas P, Ioannidis JPA. Benzodiazepines for alcohol withdrawal. The Cochrane Database of Systematic Reviews 2005, Issue 3.

Polycarpou A, Papanikolaou P, Ioannidis JPA,Contopoulos-Ioannidis DG. Anticonvulsants for alcohol withdrawal. The Cochrane Database of Systematic Reviews 2005, Issue 3.

The Cochrane Collaboration is an international nonprofit, independent organization that produces and disseminates systematic reviews of health care interventions and promotes the search for evidence in the form of clinical trials and other studies of interventions. Visit cochrane.org for more information.

Christos Ntais
cntais@hol.gr
Center for the Advancement of Health
http://www.cfah.org