NR 565 Pharmacology Week 1 Questions and Answers Already Passed

NR 565 Pharmacology Week 1 Questions and Answers Already Passed Pharmacokinetics The study of drug absorption, distribution, metabolism, and excretion in the body "What the body does to the drug" Factors that affect drug absorption (5) Rate of dissolution Surface area Blood flow Lipid solubility PH partitioning Factors that affect drug distribution (4) Blood flow to tissues Ability to exit vascular system Blood-brain barrier Protein-binding capacity Pharmacodynamics The study of biochemical and physiologic effects of drugs on the body and the molecular mechanisms by which those effects are produced "What the body does to the drug" Phamacodynamics: 3 mechanisms of action Receptor Enzyme Non-selective interactions (i.e. chemo) Types of drug therapy (7) Acute Maintenance (HTN/bc) Supplemental (insulin) Palliative Supportive (IV fluid) Prophylactic Empirical (broad-spectrum abx) Idiosyncratic Effect Unexpected response to medication Tolerance Declining response to a drug Dependence Physiological/psychological need for a drug; needs drug for normal function Addiction Compulsive use of a drug despite negative/dangerous effects Drug interactions: drug-drug When 2 drugs compete for metabolizing enzymes Drug interactions: food-drug Grapefruit juice or leafy greens Drug interactions: additive 1+1 = 2; both provide intended effect Drug interactions: antagonistic 1+1 = <2; less than desired effect of one or both drugs Drug interactions: synergistic 1+1 = >2; sum total effect is greater than if given alone (i.e. lisinopril + HCTZ) Drug interactions: incompatibility 1+1 does not equal 2; two IV drugs given together causing decomposition of one or both drugs 8 rights of medication administration Patient Medication Dose Route Time Reason Response Documentation Adverse reactions: pharmacologic Extension of a drug's normal effect Adverse reactions: Allergic/hypersensitivity Exaggerated immune response (i.e. mild itching to anaphylaxis) Adverse reactions: idiosyncratic Peculiar to the patient Adverse reactions: drug reaction Most complex, difficult to determine Teratogenic effects Causes birth defects Mutagenic effects Able to cause changes in genetic tissue Carcinogen Substances that can cause cancer Toxicology The study of adverse effects of chemicals and their compounds on living organisms and tissues 4 components of pharmacokinetics Absorption, distribution, metabolism, excretion Onset of action The time it takes for medication to take effect Time to peak effect Time before medication is at height of effect Duration of action How long therapeutic effect lasts Half-life Time required for half of a chemical to be eliminated Steady state Amount of drug going in = amount of drug going out Peak Highest level of the drug achieved Trough The level of a drug concentration immediately before next dose Duration Length of time drug remains active; measured from therapeutic level to when elimination decreases level below therapeutic range Absorption The movement into the bloodstream for distribution Bioavailability The extent to which a medication can be absorbed Absorption: enteral GI tract > bloodstream > liver = 1st pass effect Causes of decreased enteral absorption Bariatric surgery (decreased surface area) Vigorous activity (blood shunted away from GI tract) Age (decreased motility) Parenteral medications No 1st pass effect; 100% available as they enter the bloodstream Topical medication administration sites Skin, eyes, ears, nose, rectum, vagina Purpose of topical medication application Intended for action at the site of application Transdermal medications: intention Internal effect Transdermal medications: absorption Carried through skin to bloodstream; no 1st pass effect Transdermal medications: sites Rotate sites to prevent irritation Trunk or upper extremities with good circulation Avoid scar tissue due to decreased absorption Inhaled medications Intented for lungs and/or other areas of the body Distribution: transport Most rapid in areas with high blood flow (major organs) Slower to fat, skin, and muscles (increased by physical activity) Distribution: elimination Occurs primarily in the liver and kidneys Watch for renal/liver toxicity Distribution: decreased albumin Can increase risk of toxicity in burns, starvation, negative nitrogen balance Metabolism When a substance is irreversibly transformed into metabolites Excretion Elimination of a substance from the body Agonist A drug that binds to and activates a receptor Agonist: full High efficacy, full response Agonist: partial Lower efficacy, sub-maximal activation when occupying all receptors Agonist: inverse Produces opposite effect yet binds to the same receptors as agonist Silent antagonist Neutral antagonist