Withdrawal smokers feel when trying to quit may not all be due to nicotine

Virginia Commonwealth University researchers have found that smoking nicotine-free cigarettes may be sufficient for suppressing some tobacco withdrawal symptoms such as a desire for sweets, hunger and the urge to smoke, suggesting that the withdrawal smokers feel when trying to quit may not all be due to nicotine.

These findings may help experts develop improved treatment strategies to help smokers break the habit more effectively.

In the April issue of the journal Addiction, researchers reported that smoking-related stimuli, such as the smell and taste that comes from smoking nicotine-free cigarettes, were sufficient for suppressing some symptoms of tobacco abstinence such as the craving for sweets, and the urge to eat and smoke over a five-day period; while a combination of nicotine and smoking-related stimuli was adequate to suppress other withdrawal symptoms like difficulty concentrating, increased appetite, restlessness and impatience.

“People who smoke find quitting difficult due to adverse reactions associated with withdrawal,” said co-author of the study Thomas Eissenberg, Ph.D., of VCU’s Department of Psychology and the VCU Institute for Drug and Alcohol Studies. “Understanding which withdrawal symptoms are suppressed by nicotine and which are suppressed by other factors is critical in order to improve treatment options.”

One factor that contributes to tobacco withdrawal is a physical dependence on nicotine, a mild stimulant that can partially suppress withdrawal symptoms when used as a method to quit smoking. For this reason, many stop-smoking programs use nicotine gum, nicotine patches and other forms of nicotine replacement therapy to ease withdrawal. Withdrawal symptoms may include headache, weight gain, and increased urges to smoke.

In the study, 13 women and 19 men, aged 18 to 50, participated in three, five-day conditions in which they smoked either no cigarettes, nicotine-free cigarettes or cigarettes containing nicotine. Each day, participants responded to a questionnaire that assessed urges to smoke, irritability, difficulty concentrating, restlessness, impatience, craving, insomnia, increased eating and desire for sweets. In addition to these measures, researchers recorded heart rate, skin temperature and blood pressure on a daily basis.

Researchers compared how participants felt when they did not smoke to how they felt when they smoked nicotinized cigarettes or nicotine-free cigarettes. When participants did not smoke, they experienced withdrawal and did not feel well. However, when participants smoked nicotine-free cigarettes — partial withdrawal suppression — they felt better, but not as good as they felt when they smoked nicotinized cigarettes.

“Therefore, some non-nicotine factors play an important role in suppressing withdrawal and may be a valuable adjunct to nicotine replacement products like the patch and gum,” Eissenberg said. “When smokers quit, they need nicotine replacement to suppress some withdrawal symptoms, but will likely require additional therapies – either behavioral or pharmacological – to help cope with urges to smoke, hunger and other withdrawal symptoms.”

“As the discrimination of tobacco withdrawal symptoms becomes clearer, more targeted interventions may be provided and may help to improve current cessation treatments,” Eissenberg added.

The study was supported by a $2.3 million grant from the National Institutes of Health and a $400,000 grant from the Virginia Tobacco Settlement Foundation. "