Hooked on a feeling.

Researchers have had difficulty finding evidence that the addictive pull of nicotine and other drugs derives in any way from the unpleasant physical reactions people have when they try to kick the habit. Many recovering addicts, for instance, succumb to temptation long after shedding such withdrawal symptoms as shaking and nausea.

However, withdrawal encompasses a range of potentially long-lived emotional responses in drug abusers that can usher them back into addiction, contends Timothy B. Baker of the University of Wisconsin-Madison. Many smokers trying to give up cigarettes encounter an initial spike in irritability, depression, and other negative emotions, Baker says.

These feelings then diminish for a week or two before intensifying again, culminating in a return to cigarette use about a month after having stopped smoking, Baker finds. Individuals who exhibit particularly intense mood drops in the first 5 days after giving up cigarettes usually throw in the towel within the next 2 weeks.

Baker and his colleagues compiled profiles of daily emotional and physical withdrawal symptoms over 2 months for 50 cigarette smokers using nicotine patches in an attempt to quit.

Ex-smokers often suffer from intermittent bouts of emotional withdrawal symptoms, Baker concludes. The welling up of these dark feelings may stem from extended mourning for the loss of pleasure, security, and other elements of an individual's smoking experience, he proposes.