While it can be tempting to try a drug or addictive activity for the first time, it’s all too easy for things to go south – especially in the case of drug and alcohol abuse. When a person consumes a substance repeatedly over time, they begin building a tolerance. A tolerance occurs when you need to use larger amounts of drugs or alcohol to achieve the same effects as when you started.

Prolonged substance abuse can result in a dangerous cycle of addiction — where a person needs to continue using drugs or alcohol in order to avoid the uncomfortable symptoms of withdrawal. By the time a person realizes they have a problem, drugs or alcohol have already seized control, causing them to prioritize its use over everything else that was once important in their lives.

No one ever plans to become addicted. There are countless reasons why someone would try a substance or behavior. Some are driven by curiosity and peer pressure, while others are looking for a way to relieve stress.

Children who grow up in environments where drugs and alcohol are present have a greater risk of developing a substance abuse disorder down the road. Other factors that might steer a person toward harmful substance use behavior include:

Genetics

Research estimates that genetics account for 40 to 60 percent of a person’s likelihood of developing a substance use problem.

Mental health disorders

Teens and adults with mental disorders are more likely to develop substance abuse patterns than the general population.

Addiction and the Brain

Excessive substance abuse affects many parts of the body, but the organ most impacted is the brain. When a person consumes a substance such as drugs or alcohol, their brain produces large amounts of dopamine, which triggers the brain’s reward system. After repeated drug use, the brain is unable to produce normal amounts of dopamine on its own. This means that a person will struggle to find enjoyment in pleasurable activities – like spending time with friends or family – when they are not under the influence of drugs or alcohol.