Pharmacology-Final exam Questions Complete with A+ Graded Answers

Pharmacology-Final exam Questions Complete with A+ Graded Answers Withdrawal when the drug is no longer available, the individual expresses physical signs of discomfort. the purpose of a controlled substance schedule classified according to their potential for abuse which schedule is the least addictive Schedule V (5) drugs have the lowest potential for abuse. which schedule is the most addictive Schedule I drugs have the highest potential for abuse What is the most dangerous categories of teratogenic? Pregnancy X drugs differentiate between pharmacokinetics and pharmacodynamics - Pharmacokinetics= "how drugs move through the body". - Pharmacodynamics= "How medicine changes the body" Pharmacokinetics 1. crossing membranes 2. oral entry issue 3. immune system 4. the kidney, large intestines 5. liver metabolisms Which of the following are the four categories of pharmacokinetics? 1. Diffusion, active transport, interspersing, and storage 2. Ingestion, metabolism, interspersing, and excretion 3. Absorption, distribution, metabolism, and excretion 4. Ingestion, settling, movement, and storage 3 Enzymatic activity that changes a medication into a less active form is an example of 1. pharmacodynamics. 2. active transport. 3. pharmacokinetics. 4. diffusion. 3 Rationale: Pharmacokinetics describes how drugs are handled within the body. Pharmacodynamics involves how drugs change the body. Diffusion is the movement of a chemical from an area of higher concentration to an area of lower concentration. Active transport is the movement of a chemical against concentration or gradient. examples of the absorption factor that affect the pharmacokinetics of a medication 1. Dissolution分解 rate determines how quickly the drug disintegrates and disperses into simpler forms; therefore, drug formulation is an important factor of bioavailability. 2. Drug formulation: Elixirs- fast absorption liquid formulations of an oral drug are absorbed faster than tablets or capsules of the same drug. 3. Dose: high doses- fast and rapid onset 4. Route: IV fastest, oral safest, subcutaneous is slower than IM 5. Size of drug molecule: smaller faster 6. Surface area of the absorptive site: the bigger the faster 7. Digestive motility and/or blood flow 8. Lipid solubility: lipid soluble drugs are absorbed more quickly than water soluble drugs. 9. pH: basic drugs are absorbed and distributed better in alkaline environments such as in the small intestine. The pH of the local environment directly influences drug absorption through its ability to ionize the drug. 10. Interactions with food or other meds The nurse administers medications by various routes of delivery. The nurse recognizes which route of administration as requiring higher dosages of drugs to achieve a therapeutic effect? 1. Intravenous route 2. Oral route 3. Rectal route 4. Sublingual route 2 Rationale: Oral medications pass into the hepatoportal circulation and may be completely metabolized before reaching the general circulation. This so-called "first pass effect" may necessitate the use of higher dosages of oral medications to achieve a therapeutic effect. None of the other routes, sublingual, rectal, or intravenous, are affected by the "first-pass effect." examples of the distribution factor that affect the pharmacokinetics of a medication - #1 factor is blood flow (think of the blood as the Vehicle and the drug as the PACKAGE) - Lipid solubility - Affinity - Protein binding: Albumin The nurse is reviewing the role of diffusion in the distribution of medications. Drugs that cannot be distributed by simple diffusion include those with which characteristics? 1. Large molecules 2. Ionization 3. Water-soluble agents 4. Alcohol 5. Urea 1,2,3 Rationale: Large molecules have difficulty crossing plasma membranes by simple diffusion. Ionized drugs have difficulty crossing plasma membranes by simple diffusion. These drugs may require carrier, or transport, proteins to cross membranes. Water-soluble agents have difficulty crossing plasma membranes by simple diffusion. Diffusion assumes that the chemical is able to freely cross the plasma membrane. Drugs may also enter through open channels in the plasma membrane; however, the molecule must be very small, such as alcohol or urea. Aspirin is ionized as it enters the small intestine. Which statement is accurate regarding the absorption of aspirin in the small intestine? 1. Absorption is decreased. 2. Absorption is increased. 3. Ionization has nothing to do with the absorption rate. 4. Aspirin must travel past the small intestine for absorption to occur. 1 The small intestine is a more alkaline environment, which facilitates the absorption of basic drugs. Aspirin is an acidic drug that is ionized in the small intestine and will have lower absorption rates. Higher rates of absorption occur in the stomach (an acidic environment). Absorption of aspirin occurs in the stomach. examples of the metabolism factor that affect the pharmacokinetics of a medication Biotransformation - Liver is the primary metabolism site-first past effect occurs in the liver - Followed by the kidneys and intestinal tract - CYP P450 (hepatic microsomal enzyme system) microsomal enzyme system - inactivate drugs and accelerate their excretion. ---CYP inducer increase the rate of its own metabolism, thereby reducing drugs' effect First-pass effect an important mechanism, since a large number of oral drugs are rendered 致使inactive by hepatic metabolic reactions. examples of the excretion factor that affect the pharmacokinetics of a medication Elimination or drugs occurs in kidney and liver - Removal of drugs from the body - kidney, liver - Primary site- kidneys Excretion Factors: - Liver or kidney impairment - Blood flow - Degree of ionization & pH - Lipid solubility - Drug-protein complexes (binding) - Metabolic activity - Respiratory, glandular, or biliary activity Kidney function and medication excretion - Reduced kidney function = retained drugs= increased potential for toxicity Differentiate the effects of a CYP inducer v.s. a CYP inhibitor Inducer- activate enzymes that deactivate the drug-low concentration-low efficacy Inhibitor-inhibits metabolism activation of a drug-high concentration-causing toxicity Synergism the action of drugs resulting in a potentiated加强 (more than total) effect Nursing consideration with medication excretion • ALWAYS CHECK BUN (Blood, Urine, nitrogen), CREATININE, GFR (glomerular)- blood test how well your kidneys are filtering • Alter dose if indicated • May actually need to question the order depending on the medication Prior to administering a newly prescribed antibiotic, the nurse asks the patient if any other drugs have been taken today. The patient responds, "Why do you need to know?" Which nursing responses are indicated? 1. "I need to be certain you are not taking another antibiotic." 2. "Some drugs block the action of others." 3. "Some drugs increase the activity of other drugs." 4. "The antibiotic I am about to give you is a prodrug." 5. "We don't want to increase first-pass effect." 2,3 Rationale: There are many instances when a patient is prescribed more than one antibiotic at a time. Some drug-drug interactions are antagonistic, blocking or opposing the effects of the drugs taken, and some are synergistic, resulting in a potentiated effect. Prodrugs have no pharmacologic activity unless they are first metabolized to their active form by the body. This is not dependent on whether or not other drugs are present in the system. This question has nothing to do with first-pass effect. Which values must be known in order to determine a drug's therapeutic range? 1. Toxic concentration 2. Onset of action 3. Peak plasma level 4. Absorption rate 5. Minimal effective concentration 1,5 Rational: Therapeutic range is the area between toxic concentration and minimum effective concentration. Onset of action, peak plasma level, and absorption rate are not related to therapeutic range. Plasma Half-life defined as the length of time required for the plasma concentration of a medication to decrease by one-half after administration. A patient who has received an oral medication for treatment of hives says, "How long will it be before my skin clears and quits itching?" Which concepts should the nurse consider when formulating a response? 1. The amount of time between administration and the drug taking effect is known as onset of action. 2. Peak plasma levels rarely occur with oral medications. 3. Duration of action is the amount of time a drug is effective. 4. Peak plasma level is dependent on the drug's plasma half-life (t1/2). 5. Drugs with short half-lives are ineffective in treating systemic illnesses. 1,3 Rationale: Onset of drug action represents the amount of time it takes to produce a therapeutic effect after drug administration. All medications have a peak plasma level. Duration of drug action is the amount of time a drug maintains its therapeutic effect. Peak plasma level and plasma half-life (t1/2) are related but not strictly dependent on one another. The effectiveness of a drug is not dependent on half-life as long as dosing frequency is correct. The nurse recognizes that medications can be excreted by which routes? 1. Fecal 2. Gastric 3. Glandular 4. Pulmonary 5. Renal 1,3,4,5 Drugs can be excreted via feces, the glandular system, the lungs, and the kidneys. They are not excreted through the gastric tissues. determine the necessary components of a teaching plan for medication information. • Amount of drug given • How often it is given • The route • Food • Other medications given • Other OTC and herbal supplements pharmacodynamics how medicine changes the body why is pharmacodynamics important? pharmacodynamics helps HCP determine whether a medication will provide desired effects and predict side/adverse effects