NURS 5334 Advanced Pharmacology

NURS 5334 Advanced Pharmacology Verified 100% **0 order kinetic drugs - *Phenytoin, *salicylate, *ETOH, theophylline **Clearance - Elimination of drug divided by the concentration of the drug in the plasma. **Elimination - Two routes: through the kidney (urine) and GI (bile, feces) **First pass effect - Liver encounters drug before it enters the system. Enteral drugs...intestine to portal circulation (SI to liver)...hepatic portal vein...central vein...hepatic vein...IVC...heart...body **If a patient has kidney disease you would - Decrease your maintenance dose; loading dose stays the same (doesn't affect clearance) **IV route dosing (parenteral) - Goes directly to the body. Results in 100% bioavailability. Decreasing first pass effect, decreasing absorption limitations, extractions... By passes absorption and extraction. 0 order kinetics - Constant elimination at a certain rate 1/2 life (T 1/2) - Time it takes to get rid of half of the drug 0.693 X Vd divided by clearance 1st order kinetics - **Dependent on drug concentration. More drug = more elimination 5 T1/2 - To get rid of drug in the body Absorption - Enteral route involves the GI system (oral) Parenteral route = IV, IM Transdermal = through the skin Respiratory = droplet, inhalation Additional properties of and ideal drug - Reversible action, predictability, ease of admin, freedom from drug interactions, low cost, chemical stability, simple generic name Bioavailability - How much drug makes it into the system. Must account for absorption and extraction. Clearance is affected by - Kidney function Clinical pharnacology - Study of drugs in humans Complete nursing diagnosis - A statement of the pt's actual or potential health problem, a statement of the problem's probable cause or risk factors, and the signs, symptoms, or other evidence of the problem. Statements are separated by the phrases related to and as evidenced by Containdication - A preexisting condition that precludes use of a particular drug under all but the most critical of circumstances. Define Pharmacodynamics - The impact of drugs on the body. The nature and intensity of the response to the drug. Define Pharmacokinetics - The impact of the body on drugs. How much of an administered dose gets to its sites of action. Distribution - Amount of drug in the body divided by the plasma drug concentration. Drug - Any chemical that can affect living processes Elimination constant - Clearance divided by volume of distribution. Examples of adverse effects - Anticancer drugs cab increase the risk for infection, high doses of opioids can cause respiratory depression, aspirin and other related drugs can cause severe gastric ulceration, perforation, and bleeding when take for prolonged period Extraction - How much of the drugs bioavailability can be used by the body. Factors effecting distribution - Blood flow, lipid solubility, molecular size of the drug, plasma proteins (very important) Factors that determine the intensity of drug responses - Administration, pharmacokinetics, pharmacodynamics, sources of individual variation