Self-medication refers to treating oneself without a doctor's guidance and can have benefits like quick relief but also significant dangers. Dangers include incorrect diagnosis, complications from improper use of medications, drug resistance, addiction, poisoning, and drug-drug interactions. Prescriptions from doctors are important because they are tailored to each individual case and ensure proper dosing. Drug abuse refers to inappropriate use for non-medical purposes and can progress to drug dependence over time as tolerance develops. Dependence involves both physical and psychological components and requires gradual withdrawal and other treatments.