Substance abuse disorders are major health and social problems in Bangladesh. They involve harmful use of substances such as yaba, heroin, phensedyl, and cannabis. This chapter highlights diagnostic criteria as per international guidelines, drug abuse, tolerance, and withdrawal. Risk factors include peer influence, family dysfunction, poverty, and easy access to drugs. Management includes detoxification, pharmacotherapy, counseling, and rehabilitation. Nurses address problems like risk of injury, malnutrition, and altered behavior through safety measures, education, and support. Prevention relies on awareness programs, family support, school education, and strong community-based strategies.