Nicotine Addiction
Nicotine's addiction potential lies in its ability to bind to certain brain receptors which leads to release of Dopamine.
Dopamine is responsible for the pleasure sensation and positive reinforcement of smoking. The success of Wellbutrin ( Zyban ), lied in its ability to mimic Nicotine, without having an addictive potential. Wellbutrin however did not prevent Nicotine's action in binding to receptors and producing its effect. The newly released Varenicline ( Chantix ) approved by the FDA in May 2006, binds to Nicotine specific sites, causing mild nicotine like effects and at the same time preventing Nicotine's binding at these sites. It is thus more effective than Wellbutrin in smoking cessation. Its cost is comparable to Wellbutrin, and the most common side effects are Nausea and insomnia. Varenicline is not recommended for Pregnant patients and those under 18 years of age.