A simple and workable definition of a drug is any chemical or biologic substance that affects the body and its processes. U.S. law defines a drug as a substance intended for use in the diagnosis, cure, relief, treatment, or prevention of disease or intended to affect the structure or function of the body. (Oral contraceptives are an example of drugs that affect the function of the body rather than a disease.) This comprehensive definition of a drug, although important for legal purposes, is rather complex for everyday use.
Some people incorrectly use the word drug to mean only a substance that produces a pleasurable sensation. Drug abuse—the excessive and persistent use of mind-altering substances without medical need—has accompanied the appropriate medical use of drugs throughout recorded history. Some drugs with potential for abuse have legitimate medical purposes, and others do not.
View by:
Drugs
-
Overview of Drugs
-
-
Administration and Kinetics of Drugs
-
Adverse Drug Reactions
-
Brand-Name and Generic Drugs
DrugsSections (A-Z)
Administration and Kinetics of Drugs
Adverse Drug Reactions
Brand-Name and Generic Drugs
Drug Dynamics
Factors Affecting Response to Drugs
Over-the-Counter Drugs
Overview of Drugs
Also of Interest
Test your knowledge
After being swallowed, injected, inhaled, or absorbed through the skin, most drugs enter the bloodstream and circulate throughout the body. The drugs then interact with cells or tissues where they produce their intended effects (target sites). Which of the following drugs targets mainly a single organ?
