1. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 0 Pharmacology: Principles and Applications 2 nd edition Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published.

2. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 1 Chapter 2 critical thinking case of Basics of Pharmacology Yvette, a new patient, has been diagnosed by the physician as hypertensive. The physician has prescribed two new medications for her to take. Yvette is also taking several other medications for osteoarthritis and allergies; these were prescribed by another physician, but she cannot remember all of the names. What can you do to make certain you have all the right information about Yvette’s new medications so that they will not cause any adverse or toxic reactions?

3. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 2 Learning Objectives  Providing definitions of the key words using the appendix or a medical dictionary.  Stating healthcare workers’ responsibilities in regard to adverse reactions, side effects, and toxic reactions.  Defining a drug and an ideal drug.  Describing the five fundamental categories of pharmacology and how these factors influence medications in the body.  Describing the indications of medications

4. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 3 Chapter 2 Lesson 2.1

5. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 4 What is a Drug? What is an Ideal Drug?  any chemical used for therapeutic application  can help or harm an individual  may alter biochemical function of the body

6. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 5 What is a Drug? What is an Ideal Drug? (cont’d.) Drug components Drug components  active ingredient  inert ingredient  vehicle

7. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 6 What is a Drug? What is an Ideal Drug? (cont’d.) Ideal drug: Ideal drug:  produces no side effects or adverse reactions  produces same effect each time the same dose is given  easy to administer  inexpensive  easy to pronounce, remember

8. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 7 What is a Drug? What is an Ideal Drug? (cont’d.) No drug is completely safe. No drug is completely safe.  All drugs cause some side effects or adverse reactions.  Drug must be as safe as possible.  Should have no harmful effects when taken in high doses over a long period of time.  Be aware of a drug’s effects in order to safely administer medications.

9. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 8 Five Basic Categories of Pharmacology  Pharmacognosy: origins of drugs  Pharmacokinetics: how drugs are processed by the body  Pharmacodynamics: actions of drugs on the body  Pharmacotherapeutics: effects of drugs on the body  Toxicology: the poisonous effects of drugs on the body

10. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 9 Pharmacognosy—The Origins of Drugs  Historically, drugs came from four basic sources:  plants  animals  minerals  synthetic substances  Recently, recombinant DNA technology (gene-splicing) is being used to create drugs.

11. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 10 SourceDrug Purple foxglove (digitalis) digoxin Rose hips vitamin C Cinchona bark quinidine Opium poppy morphine, codeine, paregoric Periwinkle (vinca) vincristine Snakerootreserpine Belladonna atropine, scopolamine Willow bark aspirin Castor bean castor oil Drug Sources—Plants

12. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 11 SourceDrug Gold Salganol, auranofin Zinc zinc oxide Calcium Os-Cal, Cal-Bid, CitraCal, Rolaids, Tums Magnesium Milk of Magnesia, Mylanta, Maalox Aluminum Amphojel, Gelusil Drug Sources—Minerals

13. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 12 SourceDrug Codfish cod liver oil Pancreas of cow or hog insulin Stomachs of hogs pepsin Animal thyroid glands thyroid hormone Placenta hair products Drug Sources—Animals

14. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 13 SourceDrug Inorganic sulfonamides, oral contraceptives, barbiturates Organic penicillin, cephalosporins Drug Sources—Synthetics

15. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 14 SourceDrug InsulinHumulin ErythropoietinEpogen Drug Sources—Recombinant DNA Technology

16. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 15 Pharmacokinetics—How the Body Processes Drugs Involves four processes:  Absorption: movement of a drug from its administration site into the blood  Distribution: movement of a drug from the blood into tissues and cells  Metabolism: physical and chemical alteration of a drug in the body  Excretion: removal of waste products from the body

17. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 16 Drug Activity in the Body

18. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 17 Medications are administered by three routes. Absorption

19. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 18 Absorption (cont’d.) Physical properties that affect absorption rates:  solubility  pH  absence or presence of food in stomach  fat solubility  length of contact  inhalation factors  drug concentration

20. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 19 Route of Drug Administration and Rates

21. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 20  a drug is delivered to tissues through blood vessels and capillaries.  a drug’s effect takes place in tissues, not blood vessels. Modified from Leahy, JM, Kizilay, PE (1998). Foundations of nursing practice. Philadelphia: Saunders. Distribution

22. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 21 Distribution (cont’d.) Factors affecting drug distribution:  permeability of capillaries to drug’s molecules  chemical makeup of drug  amount given  size of person  amount of protein in blood  drug’s ability to pass through tissue’s cell membrane

23. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 22 Distribution (cont’d.) Barriers to drug distribution:  Blood-brain barrier (water-soluble electrolytes cannot cross, but fat-soluble substances can)  Placental barrier (allows water and fat-soluble substances to cross)  Selective distribution (drugs are attracted to specific organ cells)

24. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 23 series of chemical reactions altering a drug by converting it into a water-soluble compound for excretion Modified from Leahy, JM, Kizilay, PE (1998). Foundations of nursing practice. Philadelphia: Saunders. Metabolism, or Biotransformation

25. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 24 Metabolism, or Biotransformation (cont’d.) Factors affecting drug metabolism:  condition of liver  first-pass effect—rapid inactivation of some oral medications by the liver  age of patient  drug half-life—time in which half the available drug is metabolized by the body for excretion

26. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 25 occurs through respiration, perspiration, urination, or defecation Modified from Leahy, JM, Kizilay, PE (1998). Foundations of nursing practice. Philadelphia: Saunders. Excretion or Elimination

27. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 26 Excretion or Elimination (cont’d.) Factors affecting rate of excretion:  chemical composition of drug  rate of metabolism  administration route  condition of excreting organs  good renal function essential  milk glands also excrete some medications  Nursing mothers should check with physician before taking any medication.

28. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 27 Review of Pharmacokinetics  Drug Administration  Routes – enteral, parenteral, percutaneous  Absorption  Absorbed and transported to site of action  Distribution  Transported to body areas via circulating fluids  Metabolism  Medication altered to be used by the body  Excretion  Unused medication removed from body

29. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 28 Pharmacodynamics—Action of Drugs in the Body  Drug action: physiological change occurring in the body in response to the drug.  Drugs cannot give body organs and tissues new functions.  Drugs can slow down or speed up cell processes.  Drugs can replace natural substances, protect body from foreign materials, and inhibit cell growth.

30. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 29 Pharmacodynamics—Action of Drugs in the Body (cont’d.) Four major effects: Four major effects:  depression: lessens body activity  stimulation: increases body activity  irritation: produces areas of inflammation  demulcence: produces soothing effect

31. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 30 Pharmacodynamics—Action of Drugs in the Body (cont’d.) Additional effects: Additional effects:  synergism: two drugs taken together boost each other’s effect.  antagonism: one drug counteracts or reduces the effect of another drug when taken together.

32. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 31 Pharmacotherapeutics—Effects of Drugs on Disease Five categories of reasons to prescribe medications: Five categories of reasons to prescribe medications:  curative: cure disease  palliative: relieve symptoms  preventative: prevent disease  diagnostic: diagnose conditions  substitutive: replace natural body substances

33. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 32 Pharmacotherapeutics—Effects of Drugs on Disease (cont’d.) Effects of drugs: Effects of drugs:  desired effect: intended response to a medication  side effect: mild, annoying, undesirable response to a medication

34. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 33 Sites of Action  Local Action  Drug action is limited to the site of administration or surrounding tissues  Systemic Action  Drug action is felt throughout the body  Remote Action  Drug action is at site distant from the site of administration

35. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 34 Toxicology—Poisonous Effects of Drugs  All drugs taken in excess act as poisons.  Medication dose can mean the difference between therapeutic effect and toxic effect.  Antidotes can be given to reverse overdose symptoms or stop toxic effects.

36. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 35 Toxicology—Poisonous Effects of Drugs (cont’d.) Unwanted effects of drugs:  adverse reaction: unintended, undesirable, often unpredictable effects causing unwanted symptoms  allergic reaction: hypersensitivity to a drug, often after just one dose  hypersensitivity reaction: cell-mediated allergic reaction

37. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 36 Anaphylaxis:  severe, potentially fatal, allergic response  occurs a short time after the drug is administered  symptoms include:  hives  reddened skin  bronchospasm  blood pressure changes  diaphoresis Toxicology—Poisonous Effects of Drugs (cont’d.)  cyanosis  dyspnea  vascular collapse  loss of consciousness  cardiac arrhythmias  cardiac arrest

38. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 37 Chapter 2 Lesson 2.2

39. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 38 Undesirable Effects  Identifying undesirable effects  Did the patient follow instructions accurately  When did the symptoms first occur? How long after the first use of the drug?  Has the patient started anything else new or changed something? Has a new household product been used?  If the drug was discontinued, did the signs and symptoms disappear?

40. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 39 Undesirable Effects (cont’d.)  If the drug was restarted did the same effects occur?  Could the illness cause the symptoms? Are the signs and symptoms consistent with the diagnosis?  Could other drug or products that are being used concurrently cause the reaction?  Is there a possibility of a drug-drug or drug-food interaction?

41. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 40 Undesirable Effects (cont’d.)  Allied health professional important in evaluating undesirable effects  Patient education should include early identification of possible unwanted reactions  Evaluate medications on an individualized basis

42. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 41 Drugs and Receptor Sites  Drugs attach to appropriate receptor sites  Drug molecules travel in the blood until they reach and attach to receptor site  The better the fit of the drug to the receptor site, the better is the expected response  Drugs may be used to prevent other chemicals from attaching to a receptor site

43. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 42 Drugs at Receptor Sites

44. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 43 Agonists vs Antagonists vs Synergism  Agonist – drug that mimics body function  May compete with previously bound drugs  Synergist – One drug potentiates another drug  Antagonist – drug that binds to a receptor site and does not activate the site  Prevents the activation of the receptor site by the agonist  Counteract the expected effects of other drugs

45. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 44 Drug-Drug Interactions  Potentiation – One drug prolongs or augments the effects of another  Tolerance – Long-term use of drug lessens the expected effect  Summation – Two drugs are given together and each drug has the expected effect  Cumulation (accumulation) – Drug is not excreted as expected and it accumulates in the body  See Table 2-8

46. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published. Slide 45 Food-Drug Interactions  Foods may react with drugs to induce toxic effects or cause failure of therapy  Absorption may be decreased by food in the stomach  Some medications must be taken with food to prevent gastric irritation  See Box 2-4

47. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published.  Yvette, a new patient, has been diagnosed by the physician as hypertensive. The physician has prescribed two new medications for her to take. Yvette is also taking several other medications for osteoarthritis and allergies; these were prescribed by another physician, but she cannot remember all of the names. What can you do to make certain you have all the right information about Yvette’s new medications so that they will not cause any adverse or toxic reactions? Slide 46