Pharm Exam 1 PDF

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Explains the basics of nursing pharmacology...

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Chapter 1 Learning Objective 1. Define a prototype drug. ● Define a prototype drug o An individual drug that represents groups of drugs o Usually the first drug of a particular class to be developed o The standard with which newer drugs in the class are compared o Ex: opioid analgesics: morphine; beta-lactam antibiotics: penicillin Learning Objective 2. Distinguish between generic and trade names of drugs. ● Distinguish between generic and trade names and how to determine whether a medication’s name is a generic or brand name. o Generic: official name ▪ Indicates the drug group ▪ Required to be therapeutically equivalent to the trade named drug ▪ May be prescribed and dispensed by generic or trade name; can be substituted for trade name drugs unless the prescriber requests the trade named medication by writing “do not substitute” on the prescription ▪ usually lowercase in name o Trade: brand name ▪ Capitalized ● generic (Trade) ● Discuss the difference between generic and brand name medications. Learning Objective 3. Describe the main categories of controlled substances in relation to therapeutic use, potential for abuse, and regulatory requirements. ● Describe the main categories of controlled substances in relation to therapeutic use and potential for abuse. (Box 1.1.) o Schedule I: Drugs that have no accepted medical use, have lack of accepted safety, and have high abuse potentials ▪ Ex: heroin, lysergic acid diethylamide (LSD), 3,4-methylenedioxy-methamphetamine (MDMA or ecstasy), mescaline, and peyote o Schedule II: Drugs that are used medically and have high abuse potentials; prescriptions cannot be refilled ▪ Ex: opioid analgesics (codeine, hydromorphone, methadone, meperidine, morphine, oxycodone); CNS stimulants (cocaine, methamphetamine), barbiturate sedative-hypnotics (pentobarbital)some CNS stimulants (methylphenidate) o Schedule III: Drugs with less potential for abuse, but abuse of which may lead to psychological or physical dependence; have an accepted medical use in the US ▪ Ex: androgens and anabolic steroids, some depressants (ketamine); mixtures containing small amounts of controlled substances (codeine) o Schedule IV: Drugs with an accepted medical use but with some potential for abuse ▪ Ex: benzodiazepines  (diazepam, lorazepam); other sedative-hypnotics (phenobarbital, chloral hydrate); some prescription appetite suppressants (phentermine) o Schedule V: Products containing moderate amounts of controlled substances; may be dispensed by a pharmacist without a prescription but with some restrictions regarding amount, record keeping, etc. ▪ Ex: cough suppressants containing small amounts of codeine and antidiarrheal drugs [diphenoxylate, atropine (Lomotil)] ● Discuss the process of inventorying and documenting how controlled substances are used. o Nurses are responsible for storing controlled substances in locked containers, administering them only to patients to whom they are prescribed, recording each dose given, maintaining an accurate inventory, and reporting discrepancies Learning Objective 4. Identify the multiple safeguards that are in place to promote drug safety in packaging, drug laws, and approval processes. ● Differentiate between prescription and over-the-counter (OTC) medications. o With prescription drugs, a health care professional diagnoses the condition and determines the need for the drug o With OTC drugs, the consumer must make these decisions, with or without consultation of a health care professional ● Discuss the advantages and disadvantages of drugs available as over-the-counter medications. o Advantages: greater autonomy, faster and more convenient access to effective treatment, possibly earlier resumption of ADLs, fewer visits to HCP, and possibly increased efforts by consumers to learn about their symptoms/conditions/treatments o Disadvantages: inaccurate self-diagnoses, potential risks of choosing wrong or contraindicated drug, delayed treatment by HCP, development of adverse drug reactions and interactions Safeguards in place to promote drug safety ● Packaging o Child safety locks on pills ● Drug Laws o The Comprehensive Drug Abuse Prevention and Control Act was passed in 1970. Title II of this law, called the Controlled Substances Act, regulates the manufacture and distribution of narcotics, stimulants, depressants, hallucinogens, and anabolic steroids and requires the pharmaceutical

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industry to maintain physical security and strict record keeping for these drugs and substances An approach known as medication-assisted treatment (MAT) may be used in the management of substance abuse disorders. MAT involves the use of FDA-approved medications in combination with counseling and behavioral therapies. The Substance Abuse and Mental Health Services Administration program provides a “whole-patient” approach to the treatment of substance use disorders that is consistent with the latest regulations that address the opioid crisis. The Substance Use-Disorder Prevention that Promotes Opioid Recovery and Treatment (SUPPORT) for Patients and Communities Act assists states in implementing updates to their plans of safe care and improving data sharing between states. It can help some people to sustain recovery. o In addition to federal laws, state laws also regulate the sale and distribution of controlled drugs. These laws may be more stringent than federal laws; if so, the stricter laws usually apply. ● Approval Process o Phase 0 ▪ drug testing occurs in animals and small groups of humans o Phase 1 ▪ a few doses are given to a certain number of healthy volunteers to determine safe dosages, routes of administration, absorption, metabolism, excretion, and toxicity o Phase 2 ▪ In Phase 2, a few doses are given to a certain number of subjects with the disease or symptom for which the drug is being studied, and responses are compared with those of healthy subjects. o Phase 3 ▪ In Phase 3, the drug is given to different populations and different dosages and by using the drug in combination with other drugs ▪ Phase 3 studies help determine whether the potential benefits of the drug outweigh the risks o Phase 4 ▪ In Phase 4, the FDA allows the drug to be marketed and requires manufacturers to continue postmarketing monitoring and electronic report submission of the drug’s safety and effectiveness. ● The FDA’s CDER approves many new prescription drugs annually, and it also approves drugs for OTC availability. Learning Objective 5. Recognize initiatives designated to enhance safe drug administration. ● Explain the guidelines for safe drug administration. o 10 Rights: drug, dose, patient, route, time, reason, documentation, education, evaluation, refusal o Technology: electronic charting, automated drug dispensing systems, bar code med administration o Error reduction strategies: having quiet zone to prepare medications, placing quiet zone signs at the entrance to the med room or above the med-dispensing system, wearing vest to signal others to avoid interrupting during med administration, educating staff to reduce interruptions of nurses administering meds o Pregnancy categories for safety ▪ the Pregnancy and Lactation Labeling Rule in 2015 provided a new system that documents exposed known or potential maternal or fetal adverse reactions with individual drugs. This classification scheme has replaced the pregnancy categories. The system is anticipated to improve communication on the best available evidence on risks associated with drug exposure in pregnancy for better-informed prescribing decisions o “Do Not Use” list o

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▪ Beers Criteria ▪ a list of medications that are generally considered best avoided generally in older adults and specifically in those with certain diseases, confirm that toxic medication effects and drug-related problems affect the safety of older adults. For a wide variety of reasons, the medications listed tend to cause adverse effects in this population and have been linked to poor health outcomes, including confusion, falls, and death. High alert medications (Box 1.2) ▪ Adrenergic agonists, IV (e.g., epinephrine, phenylephrine, norepinephrine)

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Adrenergic antagonists, IV (e.g., propranolol, metoprolol, labetalol) Anesthetic agents, general, inhaled, and IV (e.g., propofol, ketamine) Antidysrhythmics, IV (e.g., lidocaine, amiodarone) Antithrombotic agents (anticoagulants), including warfarin, low molecular weight heparin, IV unfractionated heparin, factor Xa inhibitors (fondaparinux), direct thrombin inhibitors (e.g., argatroban, lepirudin, bivalirudin), thrombolytics (e.g., alteplase, reteplase, tenecteplase), and glycoprotein IIb/IIIa inhibitors (e.g., eptifibatide) Cardioplegic solutions Chemotherapeutic agents, parenteral and oral Dextrose, hypertonic, 20% or greater Dialysis solutions, peritoneal and hemodialysis Epidural or intrathecal medications Hypoglycemics, oral Inotropic medications, IV (e.g., digoxin, milrinone) Insulin, subcutaneous and IV

▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ Discuss factors that may affect safe drug administration. o Environment, MD errors, reconciliation issues, pt interference, compatibility, fatigue, labels can be misleading

Chapter 2 Learning Objective 1. Discuss cellular physiology in relation to drug therapy. ● Explain cellular physiology, including common cellular characteristics. (Box 2.1; and Figure 2.1.) o cells exchange materials with their immediate environment; obtain energy from nutrients; synthesize hormones, neurotransmitters, enzymes, structural proteins, and other complex molecules; reproduce; communicate with one another via various biologic chemicals (neurotransmitters, hormones) ● Discuss drug effects on cells. o Cross the cell membrane to stimulate or inhibit cellular function Learning Objective 2. Describe the main pathways and mechanisms by which drugs cross biologic membranes and move through the body. ● Explain the main pathways and mechanisms by which drugs transport throughout the body. o Pathways: direct penetration of membrane by lipid soluble drugs (most common); passage through protein channels that go through the cell membrane (used by small ions [sodium, potassium]; carrier proteins that transport molecules from one side of the cell membrane to another (selective; drug’s chemical structure determines the carrier) o Mechanisms: Passive diffusion (most common)(goes from an area from higher to lower; ex GI tract to bloodstream); facilitated diffusion (with assistance of carrier proteins; active transport(low to high concentration with proteins and releases energy) Learning Objective 3. Explain each process of pharmacokinetics. ● Define pharmacokinetics and explain each process involved. o Pharmacokinetics: drug movement through the body (i.e. what the body does to the drug) to reach sites of action, metabolism, and excretion ● Discuss the processes of absorption, distribution, metabolism, and excretion. o Absorption: occurs from the time a drug enters the body to the time it enters the bloodstream to be circulated; onset of drug action is mostly determined by absorption rate; drug intensity is determined by the extent of absorption ▪ Factors: dosage form, administration route, blood flow to site of administration, GI function, presence of food/drugs o Distribution: transport of drug molecules within the body; depends mostly upon adequacy of blood circulation (rapid: heart, liver, kidneys) (slow: muscle, fat, skin) ▪ Protein binding (albumin) allows part of a drug dose to be stored and released as needed because the large size of the drug/plasma protein complex is too large to leave the bloodstream (maintaining more consistent plasma drug levels)Most drug stored by albumin o Metabolism:  method by which drugs are inactivated by the body (Biotransformation) ▪ Most often active drugs are changed into inactive metabolites, then excreted ▪ Some active drugs yield active metabolites that exert effects on body cells until metabolized further or excreted ▪ Prodrugs are inactive at first and exert no effect until they are metabolized ▪ Major function: to convert fat-soluble drugs into water-soluble metabolites that can be excreted by the kidneys (water soluble only by kidneys) ▪ Hepatic drug clearance: major mechanism for terminating drug action and eliminating drug molecules from the body o Excretion: elimination of a drug from the body; requires adequate functioning of the circulatory system, kidneys, bowel, lungs, and skin (urine, bile, feces, vomit) Learning Objective 4. Recognize individual differences in patient drug responses related to genomic variations. ● Compare and contrast individual difference in drug responses based on genomic variations.

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Genetic polymorphisms influence metabolism by producing functionally different responses to drugs in ethnic groups or specific individuals.CYP-450 liver enzymes metabolize many drugs; with chronic administration, some drugs stimulate the liver cells to produce larger amounts of enzymes which accelerates drug metabolism (requiring larger doses to maintain therapeutic effects); concurrent administration of drugs that compete for the same metabolizing enzymes delays metabolism (smaller doses required to avoid adverse effects or toxicity from drug accumulation) [ex:  cimetidine] Learning Objective 5. Discuss the clinical usefulness of measuring serum drug levels. ● Explain the purpose of measuring serum drug levels. o Provides a measurement of the amount of drug in the blood at a particular time o determine therapeutic effect ● Discuss what serum blood levels reflect. o Dosage, absorption, bioavailability(how much of a drug is available), half-life(rate or time that the concentration is set in half; 4-5 half lifes are good.), rates of metabolism and excretion ● Review the circumstances in which measuring drug serum levels is useful. o Toxic concentration o Therapeutic range: goal of drug therapy o Peak action: level of highest concentration; trophs lower levels of concentration o Drugs with a narrow margin of safety are given (therapeutic dose is close to toxic dose) [digoxin,  aminoglycoside antibiotics, lithium] o To document the serum drug levels associated with therapeutic effects or adverse effects o To monitor unexpected responses to a drug dose such as decreased therapeutic effects or increased adverse effects o When a drug overdose is suspected(respiratory depression, slow heart rate, adverse effects) Learning Objective 6. Describe major characteristics of the receptor theory of drug action. ● Define the receptor theory of drug action: most drugs exert their effects by chemically binding with receptors at the cellular level ● Explain the types of reactions involved in the receptor theory of drug action. o Activation, inactivation, and other alterations of intracellular enzymes: o Changes in the permeability of cell membranes to one or more ions o Modify the synthesis, release, or inactivation of neurohormones ● Discuss the types of medications that do not act on receptor sites. o Antacids: act chemically to neutralize hydrochloric acid and raise the ph of gastric fluid o Osmotic diuretics: increase the osmolarity of plasma and pull water out of tissues and into the bloodstream [mannitol] o Drugs structurally similar to nutrients required by body cells [anticancer  drugs] o Metal chelating agents which combine with toxic metals to form a complex that can be more readily excreted Learning Objective 7. Differentiate between agonist drugs and antagonist drugs. ● Discuss the role of receptors in the extent of drug action. o When drug molecules chemically bind with cell receptors, pharmacologic effects result from agonism or antagonism. o Minor changes in drug structure may produce major changes in pharmacologic effects. Another major factor is the concentration of drug molecules that reach receptor sites in body tissues. Drug-related and patient-related variables that affect drug actions are further described later in this chapter. ● Explain the effects of agonist medications. o Agonists are drugs that produce effects similar to those produced by naturally occurring hormones, neurotransmitters, and other substances. Agonists may accelerate or slow normal cellular processes, depending on the type of receptor activated. For example, epinephrine-like drugs act on the heart to increase the heart rate, and acetylcholine-like drugs act on the heart to slow the heart rate; both are agonists. ● Define the action of antagonist medications. o Antagonists are drugs that inhibit cell function by occupying receptor sites. This strategy prevents natural body substances or other drugs from occupying the receptor sites and activating cell functions. After drug action occurs, drug molecules may detach from receptor molecules (i.e., the chemical binding is reversible), return to the bloodstream, and circulate to the liver for metabolism and the kidneys for excretion. (acts like the cell or body sites) Learning Objective 8. List drug-related and patient-related variables that affect drug actions. ● Discuss how dosage, route, diet, and other medications can affect drug actions. o Dosage: if amount is too small or administered infrequently, no pharmacologic action occurs; if amount is too large or administered too often, toxicity occurs o Route: affect drug actions and patient responses by influencing absorption and distribution o Diet: often food slows absorption of oral drugs by slowing gastric emptying time and altering GI secretions and motility; certain foods and drugs react to create adverse reactions [MAOI  and tyramine foods; grapefruit; warfarin and vitamin K] o Drug: action of one drug may be increased/decreased by its interaction with another drug in the body; may cause competition in binding for receptor sites and affect the absorption or metabolism of the drugs ● Define interactions that can increase the therapeutic or adverse effects of medications.

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additive effects; synergism ▪ Additive effects, which occur when two drugs with similar pharmacologic actions are taken (e.g.,  ethanol + sedative drug increases sedative effects).  ▪ Synergism, which occurs when two drugs with different sites or mechanisms of action produce greater effects when taken together (e.g., acetaminophen [nonopioid analgesic] + codeine [opioid analgesic] increases analgesic effects). ● List interactions that can decrease drug effects and how they can interrupt drug therapy. o Displacement; interference ▪ Interference by one drug with the metabolism of a second drug, which may result in intensified effects of the second drug. For example, cimetidine inhibits CYP1A, CYP2C, and CYP3A drug-metabolizing enzymes in the liver and therefore interferes with the metabolism of many drugs (e.g., benzodiazepine  antianxiety and hypnotic drugs, several cardiovascular drugs).  When  these drugs are given concurrently with cimetidine, they are likely to cause adverse and toxic effects because blood levels of the drugs are higher. The overall effect is the same as taking a larger dose of the drug whose metabolism is inhibited or slowed. ▪ Displacement (i.e., a drug with a strong attraction to protein-binding sites may displace a less tightly bound drug) of one drug from plasma protein-binding sites by a second drug, which increases the effects of the displaced drug. This  increase occurs because the displaced drug, freed from its bound form, becomes pharmacologically active. The overall effect is the same as taking a larger dose of the displaced drug. For example, aspirin displaces warfarin and increases the drug’s anticoagulant effects. ● Discuss patient-related variables and their individual effects on drug therapy. o Age(decreased metabolism or immature organs), body weight, gender, genetics, ethnicity(different dosages and meds based on ethnicity) ● Outline pathologic conditions that may alter pharmacokinetic processes. o Cardiovascular (MI, heart failure, hypotension)—all processes o GI (vomiting, diarrhea, inflammatory bowel disease, trauma or surgery)-- absorption o Hepatic (hepatitis, cirrhosis, decreased liver function)--metabolism o Renal (acute or chronic renal failure)—excretion o Thyroid: metabolism ● Differentiate between drug ...