Anti-Smoking Drugs May Have Psychological Effects

Sometimes, public health messages can be pretty confusing.

The Food and Drug Administration is now requiring warning labels on two prescription drugs: varenicline, marketed as Chantix; and bupropion, marketed as Zyban. The drugs are prescribed to people who are trying to quit smoking. And quitting smoking is, of course, a good thing. But the FDA is concerned that the drugs may set off changes in behavior — hostility, agitation, depressed mood, suicidal thoughts and behaviors, and attempts at suicide.

In the past few years, the FDA has received reports of 112 cases of suicide and 205 incidents of suicidal thoughts in people taking Chantix and Zyban. But the FDA can't be sure the incidents were related to the drugs. "People who stop smoking without using medications might also experience similar-type changes because of nicotine withdrawal," says Curtis Rosebraugh, an official in the FDA's Office of Drug Evaluation.

The two drugs are different from one another. From the point of view of a cell, Chantix acts a little bit like nicotine. It attaches to the same cellular receptor and releases a chemical called dopamine. Zyban contains the same antidepressant that's in Wellbutrin. It affects the levels of a different chemical, serotonin. Wellbutrin already bears a warning label about suicidal thoughts, but whether Zyban or Chantix actually cause the behavioral problems is a mystery.

FDA officials are clear that the drugs are valuable. "We don't think people shouldn't use smoking cessation," says Robert Temple. "Smoking is really bad for you. We just don't want people using these drugs casually."

What the agency wants is for doctors and health professionals to warn their patients to look out for any effects on their behavior. Officials say patients should let their doctors know of any problems, and people should stop taking the drugs immediately and contact a health care provider if they feel agitated, depressed or start thinking about suicide.

Smoking cessation experts generally agree with the FDA's move. Steve Schroeder, head of the Smoking Cessation Leadership Center at the University of California, San Francisco, is glad the FDA isn't taking the drugs off the market. He says people need some help quitting.

"When people try to quit cold turkey, their rate of success, as measured by being quit six months later, is only about 3 percent, maybe 4," he says. Counseling alone has a 10 percent success rate. Nicotine replacement in the form of patches, inhalers and lozenges has a success rate of 10 to 20 percent in test situations. The "quit rate" with either of the two drugs plus counseling is as high as 20 to 25 percent.

It can be expensive — a month of Chantix, for example, costs $130 or more, and people may be on the drug for several months. The cost was Joanie Thompson's only complaint, even though Chantix caused her to have vivid dreams. The Rockville, Md., artist and art teacher wanted to quit for her two new grandchildren. She knew about the risk of anxiety and depression, but was surprised by the vivid dreams. "I would wake up, the dream would seem more real than lying in bed in my own room, and it would take a little while to melt away," she says.

For ex-cop Mike DeCenzo of Broadlands, Va., the issue was anxiety attacks that made it hard for him to breathe. A smoker since he was 20, he decided at the age of 57 that it was time to quit. His doctor recommended Chantix, but soon after starting the drugs, the attacks came on. He had to take an anti-anxiety drug to stop them.

Still, he's a big fan of Chantix. "I would recommend it — it worked for me," he says. "Three of us started. It worked for two out of the three, and that will get you a major league contract any day of the week," he says.

"I quit smoking last September, and I haven't picked one up since."

Still, there are reasons for concern. The Federal Aviation Administration forbids pilots and air traffic controllers from using Chantix and Zyban. Sid Wolfe of the advocacy group Public Citizen called for the warning on the labeling, and says he won't be satisfied until the manufacturers complete studies showing how often side effects occur.

Smoking cessation expert Steve Schroeder says that with the concerns, Chantix and Zyban may not be the best first choice for quitting, but if people have failed in other efforts, the drugs are worth a try. "

"This is not a drug for dandruff or hangnails; this is for the most common lethal condition in the world," he says.

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