Understanding Tobacco as a Drug of Dependence

The major conclusions of the 1988 U.S. Surgeon General's Report on The Health Consequences of Smoking - Nicotine Addiction are as follows:

1. Cigarettes and other forms of tobacco are addicting. Patterns of tobacco use are regular and compulsive, and a withdrawal syndrome usually accompanies tobacco abstinence.
2. Nicotine is the drug in tobacco that causes addiction. Specifically, nicotine is psychoactive (“mood altering”) and can provide pleasurable effects. Nicotine can serve as a reinforcer to motivate tobacco-seeking and tobacco-using behavior. Tolerance develops to actions of nicotine such that repeated use results in diminished effects and can be accompanied by increased intake. Nicotine also causes physical dependence characterized by a withdrawal syndrome that usually accompanies nicotine abstinence.
3. The pharmacologic and behavioral processes that determine tobacco addiction are similar to those that determine addiction to drugs such as heroin and cocaine.

Tobacco appears to produce more dependence than other drugs. In a review of National Comorbidity Survey data, Anthony et al. (1994) show that 32 percent of all people ever using tobacco develop nicotine dependence, as compared to 23 percent of people using heroin, 17 percent of all people using cocaine, and 15 percent of all people using alcohol that develop dependence:

In Why does smoking so often produce dependence? A somewhat different view, John Hughes notes that tobacco may be exceptionally addictive because:

1. Nicotine can offer several psychopharmacological benefits (e.g., reduce aggression, improve focus on cognitive tasks, increase vigilance, decrease weight gain, and improve mood) at the age (adolescence) when such benefits are especially needed.
2. Cigarettes provide for a rapid, frequent, reliable and easy-to-obtain reward.
3. Nicotine is not intoxicating, allowing chronic intake.
4. The long duration of the nicotine withdrawal syndrome effectively undermines cessation.

The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) includes Nicotine Dependence (305.1) and Nicotine Withdrawal (292.0). Tobacco dependence is similar, but not identical, to other substance use disorders typically treated in chemical dependency programs. In Should criteria for dependence differ across drugs?, John Hughes explores some of the similarities and differences between tobacco dependence and other chemical dependencies:

Similarities	Differences
Compulsive use	No behavioral intoxication or adverse behavioral outcomes
Continued use despite harm	Does not cause other mental disorders
Impaired control over drug use	Giving up or reducing activities to use is rare
Tolerance	High intensity of use
Withdrawal	Little euphoria
Mediated via dopamine release	Spending lots of time in obtaining/using/recovering from effects is rare
Rapid relapse	Dependence is rare in adult non-daily users
Rapid reinstatement of dependence	Prosocial beneficial effects

One of the hallmark differences between tobacco dependence and other chemical dependencies is the heightened intensity of use made possible by the lack of intoxicating properties of nicotine.

Consider this:

A person who smokes one pack (20 cigarettes) per day,
taking 10 puffs (10 doses of nicotine) per cigarette
Self administers nicotine 200 times per day

200 doses x 365 days per year=73,000 doses of nicotine per year

Next: The Toll of Tobacco Dependence on People in Treatment and Recovery >>