Millions of people in the United States smoke cigarettes and millions more drink coffee habitually. Of these individuals many are addicted to both caffeine and nicotine, and do not go through a day without caffeine and nicotine. In part, the American Society of Addiction Medicine defines addiction as, "a primary, chronic disease of brain reward, motivation, memory and related circuitry."
Nicotine
According to information found at MedlinePlus, nicotine has a potential for addiction similar to alcohol, cocaine and morphine. Nicotine can have both positive and negative effects, including elevating your mood and relieving minor depression. It also increases heart rate and blood pressure. Nicotine withdrawal symptoms can begin within two to three hours after the last tobacco use. Symptoms may include a craving for nicotine, headaches, frustration, increased appetite and depression.
Caffeine
Caffeine has not gotten the negative attention that nicotine has. The Mayo Clinic reports that moderate doses of caffeine are not harmful. It does mention that men are more susceptible to the effects of caffeine than are women and that heavy daily use can cause some negative effects, including insomnia, nervousness, restlessness, irritability, stomach upset, fast heartbeat, and muscle tremors.
Relationship Between Caffeine & Nicotine
Caffeine and nicotine are often used concurrently, though there is no pharmacological evidence of how one interacts with the other. A published report in "Psychopharmacology" 1999 by Mohammed Shoaib and his colleagues presented results of a study that suggests caffeine can increase the effectiveness of the reinforcing properties of nicotine. The study used behavioral testing with rats. Caffeine was added to the drinking water and nicotine was self-administered.
Summary
Addictions to both caffeine and nicotine are common. Caffeine serves to augment the effects of nicotine. According to a report by Stephen R. Dager and Seth D. Friedman, published in "Annals of Medicine" in 2000, neuroimaging findings associated with caffeine and nicotine consumption are limited. Such imaging modalities can explore brain functional consequences related to addictions to nicotine and caffeine.
