Unit 4 Tobacco, Alcohol, and Other Drugs Copyright Goodheart-Willcox Co., Inc. 292 Stages of Substance Use Substances such as nicotine cause changes in the brain and body that negatively affect a person’s health. People with substance use disorders often feel like they cannot stop using a substance, even if they want to. The stages of substance use lead to addiction and a substance use disorder (Figure 9.16). Experimentation People often choose to use a tobacco product “just to try it.” This is the stage of experimentation. In this stage, a person is trying a substance. Most substances that lead to substance use disorders cause pleasant feelings, such as happiness and relaxation. These feelings cause a person to want to use more of the substance, which often leads to the regular use of a substance. Regular Use After experimentation, people usually increase their substance use. Over time, people may slowly increase the number of times they use a tobacco product per week. They are then likely to develop a regular pattern of using tobacco products, as the pleasant feelings associated with the substance reinforce behavior. For example, people may vape at a certain time of day or while performing a certain activity. Tolerance As a person regularly uses a substance like nicotine, the body develops a tolerance for that substance. Tolerance describes an increase in how much of a substance the body needs to experience certain effects. The body can quickly develop a tolerance to nicotine and require more of it to achieve the original effect of pleasurable feelings. For example, during experimentation, a person may smoke one cigarette a week. This may increase to one cigarette each day with regular use. Once a tolerance develops, a person may need to smoke three cigarettes each day to feel the original effects of nicotine (Figure 9.17). A tolerance to nicotine is dangerous because it causes people to use tobacco products more as they pursue the pleasant feelings associated with the substance. This increases the damage done to the body. Even if someone is not Vaping Device Warning: Young people may be especially sensitive to nicotine, making it easier for them to become addicted. Franck Boston/Shutterstock.com Figure 9.17 Young people are extra vulnerable to many unhealthy habits, including an addiction to nicotine. Figure 9.16 People can move through the five stages of substance use disorder more quickly than they might think. Stages of Substance Use Disorder Stage 1: Experimentation Stage 2: Regular Use Stage 3: Tolerance Stage 4: Dependence Stage 5: Addiction