{"id":6702,"date":"2025-09-03T11:51:34","date_gmt":"2025-09-03T09:51:34","guid":{"rendered":"https:\/\/mediconomics.com\/glossar\/pharmacokinetics\/"},"modified":"2025-09-03T11:51:34","modified_gmt":"2025-09-03T09:51:34","slug":"pharmacokinetics","status":"publish","type":"glossary","link":"https:\/\/mediconomics.com\/en\/glossar\/pharmacokinetics\/","title":{"rendered":"Pharmacokinetics"},"content":{"rendered":"<p>Pharmacokinetics (PK) describes what the body does to a drug substance\u2014unlike pharmacodynamics (PD), which describes what the drug substance does to the body. PK comprises the four ADME processes: absorption, distribution, metabolism, and elimination. <\/p>\n<p>Key pharmacokinetic parameters for practical work in clinical trials: AUC (area under the curve): a measure of the body\u2019s total exposure to the active substance. Basis for bioequivalence comparisons. Cmax: maximum plasma concentration after a dose\u2014relevant for safety assessments (toxicity). tmax: time at which Cmax is reached\u2014dependent on route of administration and formulation.   <\/p>\n<p>Clearance (Cl): volume of plasma that is completely cleared of the active substance per unit time\u2014a measure of elimination capacity. Volume of distribution (Vd): apparent distribution volume reflecting binding of the active substance to tissues and plasma. Half-life (t\u00bd): time for the plasma concentration to decrease by half\u2014determines the dosing interval.  <\/p>\n<p>Linear vs non-linear (saturable) kinetics: In linear kinetics, clearance is concentration-independent (the more common case). In non-linear kinetics (e.g., phenytoin), enzyme systems become saturated, which makes dosing considerably more difficult. For CROs conducting Phase I trials and bioequivalence studies, correct PK sampling planning and analysis are key quality factors.  <\/p>\n<p><a href=\"https:\/\/mediconomics.com\/glossary\/\">Back to overview<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Pharmacokinetics (PK) describes what the body does to a drug substance\u2014unlike pharmacodynamics (PD), which describes what the drug substance does to the body. PK comprises the four ADME processes: absorption, distribution, metabolism, and elimination. Key pharmacokinetic parameters for practical work in clinical trials: AUC (area under the curve): a measure of the body\u2019s total exposure [&hellip;]<\/p>\n","protected":false},"author":10,"featured_media":0,"parent":0,"template":"","meta":{"_acf_changed":false,"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"glossary-cat":[],"class_list":["post-6702","glossary","type-glossary","status-publish","hentry"],"acf":[],"related_terms":"","external_url":"","internal_reference_id":"","_links":{"self":[{"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/glossary\/6702","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/glossary"}],"about":[{"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/types\/glossary"}],"author":[{"embeddable":true,"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/users\/10"}],"version-history":[{"count":0,"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/glossary\/6702\/revisions"}],"wp:attachment":[{"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/media?parent=6702"}],"wp:term":[{"taxonomy":"glossary-cat","embeddable":true,"href":"https:\/\/mediconomics.com\/en\/wp-json\/wp\/v2\/glossary-cat?post=6702"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}