GCU NUR-635 Mid-Term Study Guide – Dr. Don Marsh

GCU NUR-635 Mid-Term Study Guide – Dr. Don Marsh Pharmacology (from the Greek word ‘pharmakon,’meaning drug): the study of drugs and their structure, targets of action, mechanisms of action (MOA), distribution (how the body disburses them throughout the body), desired physiologic effects (efficacy) and undesirable side effects (toxicity). Pharmacokinetics includes ADME (absorption, distribution, metabolism and elimination). Absorption: absorption from the administration site either directly or indirectly into the blood/plasma. Distribution: reversibly/irreversibly movement of drug from the bloodstream into the interstitial and intracellular fluid. Metabolism: drug biotransformation via metabolic pathways, primarily the liver, or by other tissues. Elimination: how parent drug & its metabolites are eliminated from the body Absorption Factors: Gastrointestinal pH changes Gastric emptying Gastric/intestinal enzymes Bile acids & biliary function Gastrointestinal flora (type and quantity of bacteria) Food & nutrient interactions (most common interaction influencing GI drug absorption) Lipid solubility of the drug Distribution: Membrane permeability: Cross membranes to site of action Blood brain barrier reduces the speed of drug passage into and out of brain tissue Plasma protein binding: drugs bound to plasma proteins do not cross membranes (Note: Malnutrition = albumin = free drug = greater pharmacologic response) Aging cause a reduction in production of plasma proteins Lipophilicity of drug: lipophilic drugs concentrate in adipose tissue; remain in the body for a longer period of time