Pharmacology Proctored ATI Study Guide

Pharmacology Proctored ATI Study Guide Chapter 1: Pharmacokinetics and Routes of Administration  Absorption  Route of admin affects the rate and amount of absorption o Oral:  GI pH and emptying time  Presence of food in the stomach or intestines  Form of meds (liquid/XR) o Sublingual/buccal  Quick absorption systemically through highly vascular mucous membranes o Inhalation via mouth/nose  Rapid absorption through alveolar capillary networks o Intradermal, topical  Slow, gradual absorption o SQ/IM  Highly soluble meds have rapid absorption (10-30min), poorly soluble have slower absorption  Blood perfusion at site of injection affect absorption o IV  Immediate and complete  Distribution o Transportation of meds to sites of action by body fluids o Plasma binding protein: meds compete for protein binding sites within bloodstream, primarily albumin. The ability of med to bind to protein can affect how much med will leave and travel to target tissues.  Metabolism o Primarily occurs in the liver but can take place in the kidney o Factors that influence metabolism:  Age (infants/older adults require smaller doses)  First pass effect: liver inactivates some meds on first pass through and thus require sublingual or IV route (may need higher dose)  Excretion: o Eliminated through the kidneys. o Kidney dysfunction can result in elevated levels of medications.  Med Response o Maintain plasma levels between minimum effective concentration and the toxic concentration:  Therapeutic index (TI) o High TI has a wide safety margin. o Low TI requires monitoring of serum levels. o Tough levels: obtain immediately before next dose.