Summary NURS 403 Quiz 1 Study Sheet Mods 1-2, VERIFIED 100%,

NURS 403 – Pathophysiology/Pharmacology I Quiz 1 Study Sheet Modules 1 & 2 Module 1: Pharmacology Introduction Pharmacology Orientation Basic Terminology: • Drug: any chemical that affects living processes • Pharmacology: the study of drugs and their interactions with living systems • Clinical Pharmacology: the study of drugs and their interactions with the human body, specifically • Pharmacotherapeutics: the treatment of illnesses with medication; the use of drugs to prevent, diagnose, and treat disease, and to prevent pregnancies Properties of Drugs:  Main 3 Properties: • Efficacy: the most important property of a drug; the mechanism of action; does the drug work? • Safety: the therapeutic effects should outweigh the harmful effects • Selectivity: the drug only (or mostly) elicits the intended response  Other Properties: • Side Effects/Adverse Drug Effects • Predictability • Ease of Administration • Chemical Stability • Freedom from Drug Interactions • Low Cost • Reversible Action *Note: No drug is ideal; common misconception about drugs is that if it has ADEs, it’s ineffective; this is inaccurate because all drugs have side effects; Adverse Drug Effects (ADEs): (aka Adverse Drug Responses, ADRs) non−intended effects of a drug that could potentially be harmful • Anticancer Drugs: therapeutic effect is to kill cancer cells; ADE is infection (cyclophosphamide & methotrexate) • Opioids: therapeutic effect is analgesia; ADE is respiratory depression (morphine & meperidine) • NSAIDs: therapeutic effect is analgesia; ADE is GI tract ulceration, perforation & bleeding (Aspirin) Determinants of Drug Response Intensity: 1. Administration: refers to the dosage size, route, and timing of drug administration • Medication Errors: can be caused by improper drug administration • Patient Adherence: can be increased by ease of administration; Lack of adherence can lead to missed doses which will require patient re-education 2. Pharmacokinetics: how the drug travels through the body; the impact of the body on the drug; composed of four processes: a. Absorption b. Distribution c. Metabolism d. Excretion 3. Pharmacodynamics: how the drug interacts with the body; the impact of the drug on the body • Drug−Receptor Interactions • Patient’s Functional State • Placebo Effect 4. Individual Variations: patient variables which may affect the pharmacokinetics and pharmacodynamics of a drug action; should be evaluated before administration • Physiological Variables: Age, gender, weight • Pathological Variables: pre−existing diagnoses, Liver and Kidney Function • Genetic Variables: family histories, predispositions to altered metabolisms • Drug Interactions 1 Application in Nursing Practice The 6 Rights of Medication Administration: 1. Right Drug 2. Right Patient 3. Right Dose 4. Right Time 5. Right Route 6. Right Documentation (esp. for PRN meds) Added Later: 7. Right Assessment 8. Right Evaluation 9. Right to Patient Education 10. Right to Refuse Care • Nursing Responsibilities: the RN must first consider appropriateness, contraindications & interactions before drug administration • Ethical Issues: during drug administration, the RN is the last line of defense; if an RN is unsure of why a drug is being administered for any reason, they should STOP and speak with the APP/MD; advocate for the pt Application of Pharmacological Knowledge: A. Patient Care:  Pre-Administration Assessment: • Thorough Medication History: both Rx and OTC • Labs: should be take pre− and post− administration  Liver: liver function tests (LFT) > AST, ALT, ALP, bilirubin  Kidney: serum creatinine (SCr), creatinine clearance (CrCl), blood urine nitrogen (BUN) • Physical Evaluation and Medical History: drug pharmacokinetics could be affected by the pt’s physiological variations (age, weight, gender) or genetics • High Risk Determinants:  Kidney and Liver function, age−independent  Allergies  Pregnancy  Geriatrics & Pediatrics • Extravasation: the leaking out of drugs into the surrounding body tissues; can cause necrosis, gangrene, and even the need for amputation  Promoting Therapeutic Response & Compliance: • Self-Administration: increases compliance (e.g. inhalers & injectables) • <Ineffective= Response: ask pt about their dosage and frequency of administration • Non-Drug Measures: are complementary to medication therapy • RN Scope of Practice: RN’s can’t do anything without an order from an APP/MD/HCP B. Patient Education: • Provide all Drug Information  Minimizing ADEs: • Awareness: make patient aware of all ADEs, even if they’re benign, as they may still be disturbing to the pt if they don’t know what’s happening • Newly Diagnosed Patients: should be educated in order of importance (i.e. how to self−administer insulin, and then how to store it) • Demonstrate Technique: when possible (for self−care) • D-D & D-Food Interactions: inform pt of any interactions drug will have with other drugs or with certain foods Drug Regulation, Development, Naming & Classification Drug Regulation: • Controlled Substances Act: (1970) created 5 schedule to categorize drugs based on their capacity for abuse and dependency; formed the FDA and DEA • Drug Enforcement Agency (DEA): oversees the schedules of drugs and all other aspects of drugs (i.e. prescribing, sale, dispensing, manufacturing) • Schedule I (CI): are completely banned; lack of accepted safety under medical supervision • Schedule II (CII): referred to as <Narcotics= • Schedules III-V (CIII-V): referred to as <Controlled Substances= 2 • Federal vs State Regulations: when a state law is more stringent than a federal law, the state law is followed. o Benzodiazepines (BDZs) are CIV federally but CII at the NY State level. They’re thus treated as CII New Drug Development:  Randomized Control Trials: • Controls: a non−treatment option; ensures there’s a difference between a therapeutic outcome and a non−therapeutic outcome • Randomization: prevents allocation bias; ensures therapeutic outcome is due to the drug action and not potential individual variation among subjects • Blinding: prevents preconception bias of benefits and risks  Single-Blinded: a study in which the pt does not know whether they’re receiving the experimental drug or the control  Double-Blinded: a study in which both the pt and the researcher don’t know whether the pt is receiving the experimental drug or the control  Developmental Stages: • Preclinical: testing done in animals • Clinical: testing done in human pts • Clinical Trial Limitations: clinical trial will not uncover all ADEs as the test subjects don’t accurately represent the entire patient population who would take the drug (most test subjects are adult males, so women and children are subject to higher ADEs) • New Drugs: require post−market surveillance to monitor for unexpected ADEs; Potential benefits may be less than the ADEs Drug Names: • Chemical Name: the scientific name for a drug compound (not used) • Generic Name: (non−proprietary) should always be used; may contain class−distinguishing styles/syllables (e.g. amoxicillin is a penicillin) • Brand/Trade Name: (proprietary) an FDA approved <product= under a limited patent with a less complex name • Active Ingredients: a single product may contain several (e.g. Robitussin syrups) • International: a single product name may represent different generic drugs abroad Over-the-Counter Drugs (OTCs): • Initial Treatment: OTCs are used for initial treatment of most illnesses before they become serious • Thorough Medical History: should always include both Rx and OTC meds • Rx Strength vs OTC Strength: is essentially just dosage; no difference in <strength= Pharmacokinetics Drug Passage: A. Channels and Pores: most drugs are too large B. Transport Systems: most drugs lack receptor−specificity; transports foreign materials out of cells • P-glycoprotein (PGP): • Intestinal EpitheliumIntestinal Lumen • LiverBile • KidneysUrine • PlacentaMaternal Circulation (away from fetus) • CNS (BBB)blood 3 C. Direct Membrane Penetration: most drugs use this method • Embedded Proteins: in phospholipid bilayer facilitate drug passage  Chemistry: <like dissolves like= • Lipid Soluble Drugs: (lipophilic/hydrophobic) can easily pass across phospholipid bilayer (Absorbed) • Water Soluble Drugs: (hydrophilic/lipophobic) cannot pass through phospholipid bilayer (Excreted) D. Polarity & Ionization: • Non-Polar  Un-Ionized  Lipid Soluble  Favored for Absorption • Polar  Ionized  Water Soluble  Favored for Excretion  pH-Dependent Ionization: <like dissolves like= • Weak Acids: will move to the basic side of the membrane  Acidic Environment: a weak acid will be un−ionized and thus absorbed  Basic Environment: a weak acid will be ionized and thus excreted • Weak Bases: will move to the acidic side of the membrane  Acidic Environment: a weak base will be ionized and thus excreted  Basic Environment: a weak acid will be un−ionized and thus absorbed  Clinical Application for Overdose: • Aspirin (ASA) and Sodium Bicarbonate: ASA is a weak acid; in the event of an OD, sodium bicarbonate is given to create a basic environment, ionizing ASA and favoring it for excretion • Amphetamine and Ammonium Chloride: amphetamine is a weak base; in the event of an OD, ammonium chloride is given to create an acidic environment, ionizing amphetamine and favoring it for excretion Absorption: site of administration  blood • Rate: of absorption effects the onset of response • Extent: of absorption effects the intensity of response  Effect of Liver on Absorption: • 1st Pass Effect: PO drugs move from the GI tract  Portal Vein  Liver  General Circulation; causes a reduction in the amount of drug that reaches the bloodstream  reduction in extent of absorption  reduction in intesnity of response • Enterohepatic Recirculation: instead of passing into the general circulation, drugs move from the Liver  Bile Duct  GI Tract  Undergo Hydrolysis  Portal vein  Liver; goes through glucuronidation and causes massively reduced drug levels  Routes of Administration: A. Enteral: through the GI a. Oral (PO): by mouth; <per os= • Advantages: safer, cheaper, easier  Disadvantages: • Slow onset – not ideal for emergencies • Limited Control of plasma levels • 1st Pass effect and digestive inactivation  Preparations: • Tablets/Capsules: beware of bioavailability differences  Enteric Coated (EC): prevents stomach from harming drug and vice versa  Sustained Release (SR): allows sustained levels for long periods; QD dosing b. Sublingual (SL): dissolved underneath tongue; avoids 1st pass effect c. Rectal (PR): <per rectum=; avoids 1st pass effect d. Buccal (BUCC): in cheek; partially avoids 1st pass effect B. Parenteral: not through the GI a. Intravenous (IV): fastest route of absorption; ideal for emergencies (e.g. extreme pain) b. Intramuscular (IM): good for drugs that would be inactivated by digestion (e.g. Pen G) c. Subcutaneous (SQ/SC): under the skin (e.g. insulin)