Anyone who's attended an Alcoholics Anonymous meeting knows instinctively what research confirms: People who are dependent on alcohol are also likely to smoke cigarettes. Depending on the cohort, anywhere from 35 percent to 95 percent of alcohol-dependent adults smoke cigarettes, compared with 21 percent of adults in the U.S. population.

Many experts believe that it's important to counsel people who are alcohol-dependent to give up smoking as well as drinking. First, most evidence indicates that giving up both habits will increase the chances of someone remaining sober. Second, it's better for overall health.

A synergistic relationship

One study of 1,508 adults found that as alcohol use increased, the odds increased that a person would begin smoking daily and develop nicotine dependence. Roughly 90 percent of people who were severely dependent on alcohol were also dependent on tobacco.

It's not clear why the two addictions seem to go hand in hand. One theory is that alcohol and nicotine, the addictive component of tobacco, somehow interact in the brain to increase dependency to both substances. Alcohol appears to enhance nicotine's pleasurable effects, boosting the urge to smoke. People who are alcohol-dependent may also rely on nicotine's ability to improve attention and cognition.

Treatment options

A common worry is that trying to quit smoking and drinking at the same time will undermine treatment for alcohol dependence. However, most studies have reported that smoking cessation efforts either have no impact on maintaining sobriety, or actually improve outcomes for alcohol treatment.

However, people dependent on alcohol do face particular challenges when it comes to quitting smoking. Alcohol-dependent adults tend to smoke more than other adults, become more dependent on nicotine, and may experience more intense nicotine withdrawal.

There are no smoking cessation guidelines designed specifically for alcohol-dependent adults. For now, the best option is to follow the federal guidelines for treating tobacco dependence, which recommend a combination of counseling and medication for optimal outcome.

Counseling options include psychotherapy, behavioral therapy, or attendance at a 12-step meeting or other support group. Nicotine replacement therapy can help to alleviate withdrawal symptoms, but may not be sufficient on its own.

Two stop-smoking medications, bupropion (Wellbutrin, but the identical drug is marketed to smokers as Zyban) and varenicline (Chantix), can supplement nicotine replacement.

Bupropion may not be the best choice for people who are still alcohol-dependent or heavy drinkers. This medication can lower the threshold for seizures, and, when combined with large amounts of alcohol, can increase the risk of blackouts or seizures. And a study reported in 2007 found that bupropion did not improve the ability of alcohol-dependent adults taking nicotine replacement to stop smoking more than did nicotine replacement alone.

Varenicline has not yet been studied in alcohol-dependent adults, but studies in the general population have found that it quadruples the chances of smoking cessation in the short term and increases the likelihood of staying free of cigarettes. This medication does not carry any extra risks when used by people who are or have been heavy drinkers.