Did you know that Nicotine from cigarettes is as addictive as heroin?  Nicotine addiction is hard to beat because it changes your brain. The brain develops extra nicotine receptors to accommodate the large doses of nicotine from tobacco. When the brain stops getting the nicotine it’s used to, the result is nicotine withdrawal. You may feel anxious, irritable, and have strong cravings for nicotine.