Drugs

Drugs are chemical substances that alter the functions of the body or mind. They may have therapeutic uses when used under medical supervision, or they may be used recreationally or illegally to change mood, perception, or consciousness. Drugs can be natural, such as plant-derived alkaloids; synthetic, produced by chemical processes; or semi-synthetic. They can be administered in various forms, including pills, injections, inhalation, or topical applications, and their effects depend on dose, route of administration, age, health, and interactions with other substances.

Pharmacology studies how drugs interact with biological systems. Pharmacodynamics describes the effects of drugs on the body, while pharmacokinetics covers absorption, distribution, metabolism, and excretion. The safety and efficacy of drugs are evaluated in clinical trials before regulatory approval.

Categories include legal prescription medications, over-the-counter drugs, and non-medical or illicit drugs. Prescription drugs require medical oversight and may have strict schedules to balance benefit and risk. Illicit drugs are regulated or prohibited in most jurisdictions due to safety concerns.

Common drug classes include stimulants, depressants, opioids, hallucinogens, and cannabinoids, among others. They carry risks such as adverse effects, interactions, dependence, tolerance, withdrawal, and overdose. Public health responses focus on prevention, education, treatment, and harm reduction.

Regulatory frameworks govern approval, labeling, scheduling, and monitoring of drug safety. Ongoing research continues to inform medical use and public health policy.