Smoking Cigarettes Increases Risk of Cocaine Addiction

The concept of gateway drugs has always been sort of controversial, with many arguing that drugs like alcohol, tobacco and marijuana are used first simply because they are more available and socially accepted than harder drugs, like cocaine.

Researchers at Columbia University, however, say that the nicotine in cigarettes may well act as a true gateway drug by a mechanism in which it amplifies the effects of cocaine and increases the risks of cocaine addiction and that when people want to quit using cocaine, they might want to consider butting out their cigarette habit at the same time.

• The researchers found that rats treated with a nicotine solution for some days before being given access to cocaine developed much stronger addictions than rats given the same access to cocaine, but not pretreated with nicotine.
  
• When the cocaine was intruded before the nicotine, the cocaine did not cause an increased nicotine addiction
  
• When the rats were given the nicotine solution for a period but then denied nicotine for 7 days prior to being given cocaine they showed no increased propensity for cocaine than the rats who had never been treated with nicotine.

Looking closely at what was happening here, the scientists discovered that nicotine caused a change in the way the FosB gene worked in the brain and this change in gene expression amplified the feel-good effects of cocaine and caused an increased addiction risk.

The study authors suggest that people in recovery from cocaine addiction try to quit smoking as a way to reduce their relapse risk. They caution that using nicotine replacement products, such as nicotine gums or the nicotine patch, may not be an effective way to reduce relapse risk, since it is the nicotine and not the smoking that is amplifying the effects of cocaine.

The full research results can be found in the Nov 2 edition of Science Translational Medicine