What is drug absorption?

Drug absorption refers to the process by which a drug enters the bloodstream following administration. This is an essential step in pharmacokinetics, as it determines how quickly and effectively a drug reaches its systemic circulation and consequently its site of action. The rate and extent of absorption can influence the drug's efficacy and the onset of therapeutic effects.

Factors that affect drug absorption include the formulation of the drug, the route of administration (such as oral, intravenous, or subcutaneous), and the presence of food or other substances in the gastrointestinal tract. Understanding absorption is crucial for optimizing drug therapy and ensuring that patients receive the intended therapeutic benefits of medications.

The other options refer to different pharmacological processes: drug elimination involves the removal of the drug from the body, metabolism refers to the chemical alteration of drugs often occurring in the liver, and side effects represent the unintended consequences of drug therapy, all of which are not related to the primary definition of drug absorption.