Substance abuse and addiction are not exactly the same but are related. Substance abuse refers to the use of a substance, such as drugs or alcohol, in a way that is harmful or unhealthy. Addiction, on the other hand, refers to a more severe and chronic condition characterized by a compulsive need to use a substance despite the harmful consequences. Addiction is a type of substance use disorder, which can range from mild to severe. So while all addiction involves substance abuse, not all substance abuse leads to addiction.