This text provides a comprehensive overview of substance-related and addictive disorders, defining them as chronic brain diseases rather than choices of character. It details the clinical characteristics, intoxication symptoms, and withdrawal processes associated with a wide range of substances, including alcohol, opioids, stimulants, and caffeine. The source emphasizes the nursing process, outlining how healthcare professionals screen for dependency, manage acute overdoses, and support long-term recovery through pharmacotherapy and psychotherapy. Additionally, it explores the systemic physical damage caused by prolonged misuse and the impact of co-occurring psychiatric conditions on treatment. The material also covers process addictions like gambling, highlighting how compulsive behaviors activate the brain's reward pathways similarly to drugs. Finally, it describes a continuum of care that moves from medically supervised detoxification to community-based support groups.