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Definition of Drug Dynamics


Abimbola Farinde

, PhD, PharmD, Columbia Southern University, Orange Beach, AL

Last full review/revision Jun 2021| Content last modified Jun 2021

Drug dynamics (pharmacodynamics) involves what a drug does to the human body.

Drug dynamics describes the following properties of drugs:

  • Therapeutic effects (such as relief of pain and reduction of blood pressure)
  • Side effects (see Drug Action and Chemical Interactions)
  • Where the drug acts on the body (site of activity)
  • How the drug acts on the body (mechanism of action)

A drug’s effects on the body may be influenced by many factors, such as

  • A person’s age (see Aging and Drugs)
  • A person's genetic makeup
  • The presence of other medical conditions in addition to the one being treated (see Overview of Response to Drugs)

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