Caffeine and nicotine belong to the stimulant family of drugs. They increase heart rate and speed up other bodily functions, and have the potential to cause overdose or be habit-forming. Despite the risks associated with these substances, both caffeine and nicotine are legal to purchase and consume in the United States.
Nicotine occurs naturally in all tobacco products, including snuff, cigarettes, cigars and pipe tobacco. It is the psychoactive substance responsible for tobacco's mood-altering effects, as well as its addictive properties.
Caffeine is present naturally in tea, coffee, cocoa beans and herbs like guarana and yerba mate. It is often added to soda, energy supplements and weight loss products for its stimulating effects and can be found in a number of over-the-counter allergy medicines and pain relievers.
Both caffeine and nicotine are stimulants. They speed bodily functions and bring about temporary feelings of enhanced energy and vitality in most users.
Caffeine is consumed mainly for its energizing effects. It temporarily fights fatigue and improves mental focus, resulting in improved mood and concentration. It constricts blood vessels to help relieve allergy symptoms and headache, hence its inclusion in many over-the-counter medications. Other effects may include insomnia, jitteriness, nausea and rapid heart rate.
Like caffeine, nicotine constricts blood vessels and speeds heart rate and cognitive functioning. It attaches to acetylcholine receptors in the brain, often leading to additional effects like appetite suppression, nausea and dry mouth. Nicotine is highly addictive and can cause severe withdrawal symptoms that make it extremely difficult to quit.
Nicotine carries a number of health risks. Apart from the harmful effects of tobacco, nicotine is a poison capable of causing death in relatively low doses. The nicotine in gums and patches can even lead to health problems, especially when combined with cigarettes and other tobacco products. Nausea, dizziness and lightheadedness are common among first-time tobacco users, though these effects generally fade with time. According to the New York Times, symptoms of nicotine poisoning include abdominal cramps, vomiting, convulsions, agitation and changes in breathing and blood pressure.
When used in moderation, caffeine does not generally cause serious health risks. Due to its ability to induce bladder spasms, caffeine can cause urinary tract irritation in sensitive individuals, according to Mayo Clinic. Caffeine can magnify the effects of other stimulants like pseudoephedrine and amphetamines, increasing the risks for cardiovascular side effects like tachycardia and high blood pressure.
Addiction and Withdrawal
According to the National Institutes on Drug Abuse, nicotine is as addictive as heroin or cocaine, with a cessation rate of only one in 10 among smokers who started before the age of 21. It increases levels of the neurotransmitter dopamine---the brain's reward chemical---reinforcing the need to use the substance repeatedly. It also causes severe withdrawal symptoms upon cessation, some of which include anxiety, increased appetite, irritability and intense cravings for the drug.
Caffeine is also addictive, though considerably less so. Excessive caffeine consumption can lead to insomnia, which results in next-day fatigue and the need for more caffeine. Withdrawal effects like headache, irritability and drowsiness can add to the difficulty of quitting and may be severe enough to interfere with daily functioning.
Interactions and Precautions
Many people consume caffeine and nicotine concurrently with no obvious problems. Still, the combined stimulant effects may lead to increased cardiovascular strain and psychological side effects like irritability and anxiety. People with a history of heart disease or other chronic illness should consult a doctor before consuming caffeine, and should avoid nicotine exposure altogether.