1. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacologic Principles FROM: Pharmacology and the Nursing Process Lilley, Harrington, & Snyder Chapter 2

2. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacologic Principles Drug Any chemical that affects the processes of a living organismAny chemical that affects the processes of a living organism

3. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacologic Principles Pharmacology The study or science of drugsThe study or science of drugs

4. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacologic Principles: Drug Names Chemical name The drug’s chemical composition and molecular structureThe drug’s chemical composition and molecular structure Generic name (nonproprietary name) Name given by the United States Adopted Name CouncilName given by the United States Adopted Name Council Trade name (proprietary name) The drug has a registered trademark; use of the name restricted by the drug’s owner (usually the manufacturer)The drug has a registered trademark; use of the name restricted by the drug’s owner (usually the manufacturer)

5. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacologic Principles: Drug Names Chemical name (+/-)-2-(p-isobutylphenyl) propionic acid(+/-)-2-(p-isobutylphenyl) propionic acid Generic name ibuprofenibuprofen Trade name MotrinMotrin

6. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Instructors may wish to use EIC Image #3: The Chemical, Generic, and Trade Names for the Common Analgesic Ibuprofen

7. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacologic Principles PharmaceuticsPharmaceutics PharmacokineticsPharmacokinetics PharmacodynamicsPharmacodynamics PharmacotherapeuticsPharmacotherapeutics PharmacognosyPharmacognosy

8. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacologic Principles Pharmaceutics The study of how various drug forms influence pharmacokinetic and pharmacodynamic activitiesThe study of how various drug forms influence pharmacokinetic and pharmacodynamic activities

9. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacologic Principles Pharmacokinetics The study of what the body does to the drug:The study of what the body does to the drug: –Absorption –Distribution –Metabolism –Excretion

10. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacologic Principles Pharmacodynamics The study of what the drug does to the body :The study of what the drug does to the body : –The mechanism of drug actions in living tissues

11. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacologic Principles Pharmacotherapeutics The use of drugs and the clinical indications for drugs to prevent and treat diseasesThe use of drugs and the clinical indications for drugs to prevent and treat diseases

12. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacologic Principles Pharmacognosy The study of natural (plant and animal) drug sourcesThe study of natural (plant and animal) drug sources

13. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Drug Absorption of Various Oral Preparations Liquids, elixirs, syrupsFastest Suspension solutions  Powders  Capsules  Tablets  Coated tablets  Enteric-coated tabletsSlowest

14. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacokinetics: Absorption The rate at which a drug leaves its site of administration, and the extent to which absorption occurs.The rate at which a drug leaves its site of administration, and the extent to which absorption occurs. –Bioavailability –Bioequivalent

15. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacokinetics: Absorption Factors That Affect Absorption Administration route of the drugAdministration route of the drug Food or fluids administered with the drugFood or fluids administered with the drug Dosage formulationDosage formulation Status of the absorptive surfaceStatus of the absorptive surface Rate of blood flow to the small intestineRate of blood flow to the small intestine Acidity of the stomachAcidity of the stomach Status of GI motilityStatus of GI motility

16. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacokinetics: Absorption Routes A drug’s route of administration affects the rate and extent of absorption of that drug.A drug’s route of administration affects the rate and extent of absorption of that drug. –Enteral –Parenteral –Topical

17. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacokinetics: Absorption Enteral Route Drug is absorbed into the systemic circulation through the oral or gastric mucosa, the small intestine, or rectum.Drug is absorbed into the systemic circulation through the oral or gastric mucosa, the small intestine, or rectum. –Oral –Sublingual –Buccal –Rectal

18. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. First-Pass Effect The metabolism of a drug and its passage from the liver into the circulation. A drug given via the oral route may be extensively metabolized by the liver before reaching the systemic circulation (high first-pass effect).A drug given via the oral route may be extensively metabolized by the liver before reaching the systemic circulation (high first-pass effect). The same drug—given IV—bypasses the liver, preventing the first-pass effect from taking place, and more drug reaches the circulation.The same drug—given IV—bypasses the liver, preventing the first-pass effect from taking place, and more drug reaches the circulation.

19. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. First-Pass Effect

20. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. First-Pass Effect Routes that bypass the liver:Routes that bypass the liver: –SublingualTransdermal –BuccalVaginal –Rectal*Intramuscular –IntravenousSubcutaneous –IntranasalInhalation *Rectal route undergoes a higher degree of first- pass effects than the other routes listed.

21. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacokinetics: Absorption Parenteral Route Intravenous*Intravenous* IntramuscularIntramuscular SubcutaneousSubcutaneous IntradermalIntradermal IntrathecalIntrathecal IntraarticularIntraarticular *Fastest delivery into the blood circulation

22. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacokinetics: Absorption Topical Route Skin (including transdermal patches)Skin (including transdermal patches) EyesEyes EarsEars NoseNose Lungs (inhalation)Lungs (inhalation) VaginaVagina

23. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacokinetics: Distribution The transport of a drug in the body by the bloodstream to its site of action. Protein-bindingProtein-binding Water soluble vs. fat solubleWater soluble vs. fat soluble Blood-brain barrierBlood-brain barrier Areas of rapid distribution: heart, liver, kidneys, brainAreas of rapid distribution: heart, liver, kidneys, brain Areas of slow distribution: muscle, skin, fatAreas of slow distribution: muscle, skin, fat

24. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacokinetics: Metabolism (also known as Biotransformation) The biologic transformation of a drug into an inactive metabolite, a more soluble compound, or a more potent metabolite. Liver (main organ)Liver (main organ) KidneysKidneys LungsLungs PlasmaPlasma Intestinal mucosaIntestinal mucosa

25. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacokinetics: Metabolism Factors that decrease metabolism: Cardiovascular dysfunctionCardiovascular dysfunction Renal insufficiencyRenal insufficiency StarvationStarvation Obstructive jaundiceObstructive jaundice Slow acetylatorSlow acetylator Erythromycin or ketoconazole drug therapyErythromycin or ketoconazole drug therapy

26. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacokinetics: Metabolism Factors that increase metabolism: Fast acetylatorFast acetylator BarbituratesBarbiturates Rifampin therapyRifampin therapy

27. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacokinetics: Metabolism Delayed drug metabolism results in: Accumulation of drugsAccumulation of drugs Prolonged action of the effects of the drugsProlonged action of the effects of the drugs Stimulating drug metabolism causes: Diminished pharmacologic effectsDiminished pharmacologic effects

28. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacokinetics: Excretion The elimination of drugs from the body Kidneys (main organ)Kidneys (main organ) LiverLiver BowelBowel –Biliary excretion –Enterohepatic circulation

29. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Renal Drug Excretion

30. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacokinetics Half-Life The time it takes for one half of the original amount of a drug in the body to be removed.The time it takes for one half of the original amount of a drug in the body to be removed. A measure of the rate at which drugs are removed from the body.A measure of the rate at which drugs are removed from the body.

31. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Drug Half-Life

32. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacodynamics Drug actions: The cellular processes involved in the drug and cell interactionThe cellular processes involved in the drug and cell interaction Drug effect: The physiologic reaction of the body to the drugThe physiologic reaction of the body to the drug

33. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacodynamics Onset The time it takes for the drug to elicit a therapeutic responseThe time it takes for the drug to elicit a therapeutic responsePeak The time it takes for a drug to reach its maximum therapeutic responseThe time it takes for a drug to reach its maximum therapeutic response Duration The time a drug concentration is sufficient to elicit a therapeutic responseThe time a drug concentration is sufficient to elicit a therapeutic response

34. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacodynamics: Mechanisms of Action The ways by which drugs can produce therapeutic effects: Once the drug is at the site of action, it can modify the rate (increase or decrease) at which the cells or tissues function.Once the drug is at the site of action, it can modify the rate (increase or decrease) at which the cells or tissues function. A drug cannot make a cell or tissue perform a function it was not designed to perform.A drug cannot make a cell or tissue perform a function it was not designed to perform.

35. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacodynamics: Mechanisms of Action Receptor interactionReceptor interaction Enzyme interactionEnzyme interaction Nonspecific interactionsNonspecific interactions

36. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Drugs and Receptors Drugs and Receptors

37. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Drug-Receptor Interactions: Definitions

38. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacotherapeutics: Types of Therapies Acute therapyAcute therapy Maintenance therapyMaintenance therapy Supplemental therapySupplemental therapy Palliative therapyPalliative therapy Supportive therapySupportive therapy Prophylactic therapyProphylactic therapy

39. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacotherapeutics: Monitoring The effectiveness of the drug therapy must be evaluated.The effectiveness of the drug therapy must be evaluated. One must be familiar with the drug’s intended therapeutic action (beneficial) and the drug’s unintended but potential side effects (predictable, adverse drug reactions).One must be familiar with the drug’s intended therapeutic action (beneficial) and the drug’s unintended but potential side effects (predictable, adverse drug reactions).

40. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacotherapeutics: Monitoring Therapeutic indexTherapeutic index Drug concentrationDrug concentration Patient’s conditionPatient’s condition Tolerance and dependenceTolerance and dependence InteractionsInteractions Side effects/adverse drug effectsSide effects/adverse drug effects

41. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacotherapeutics: Monitoring Therapeutic Index The ratio between a drug’s therapeutic benefits and its toxic effectsThe ratio between a drug’s therapeutic benefits and its toxic effects

42. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacotherapeutics: Monitoring Tolerance A decreasing response to repetitive drug dosesA decreasing response to repetitive drug doses

43. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacotherapeutics: Monitoring Dependence A physiologic or psychological need for a drugA physiologic or psychological need for a drug

44. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacotherapeutics: Monitoring Interactions may occur with other drugs or food Drug interactions: the alteration of action of a drug by:Drug interactions: the alteration of action of a drug by: –Other prescribed drugs –Over-the-counter medications –Herbal therapies

45. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacotherapeutics: Monitoring Interactions Additive effectAdditive effect Synergistic effectSynergistic effect Antagonistic effectAntagonistic effect IncompatibilityIncompatibility

46. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacotherapeutics: Monitoring Medication Misadventures Adverse drug events ALL are preventableALL are preventable Medication errors that result in patient harmMedication errors that result in patient harm Adverse drug reactions Inherent, not preventable event occurring in the normal therapeutic use of a drugInherent, not preventable event occurring in the normal therapeutic use of a drug Any reaction that is unexpected, undesirable, and occurs at doses normally usedAny reaction that is unexpected, undesirable, and occurs at doses normally used

47. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacotherapeutics: Monitoring Some adverse drug reactions are classified as side effects. Expected, well-known reactions that result in little or no change in patient managementExpected, well-known reactions that result in little or no change in patient management Predictable frequencyPredictable frequency The effect’s intensity and occurrence is related to the size of the doseThe effect’s intensity and occurrence is related to the size of the dose

48. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacotherapeutics: Monitoring Adverse Drug Reaction An undesirable response to drug therapy IdiosyncraticIdiosyncratic Hypersensitivity reactionsHypersensitivity reactions Drug interactionsDrug interactions

49. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacotherapeutics: Monitoring Iatrogenic Responses Unintentional adverse effects that are treatment-induced DermatologicDermatologic Renal damageRenal damage Blood dyscrasiasBlood dyscrasias Hepatic toxicityHepatic toxicity

50. Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved. Pharmacotherapeutics: Monitoring Other Drug-Related Effects TeratogenicTeratogenic MutagenicMutagenic CarcinogenicCarcinogenic