1. Chapter 3 Sources and Bodily Effects of Drugs

2. Copyright © 2007 by Thomson Delmar Learning. ALL RIGHTS RESERVED.2 Sources of Drugs Plants Minerals Animals Synthetic

3. Copyright © 2007 by Thomson Delmar Learning. ALL RIGHTS RESERVED.3 Effects of Drugs All drugs affect body function in some way Drug actions –Cellular changes Drug effects –Physiological change

4. Copyright © 2007 by Thomson Delmar Learning. ALL RIGHTS RESERVED.4 Effects of Drugs Systemic effect Local effect

5. Copyright © 2007 by Thomson Delmar Learning. ALL RIGHTS RESERVED.5 Drug Processing Many variables affect the following processes –Absorption –Distribution –Metabolism –Excretion

6. Copyright © 2007 by Thomson Delmar Learning. ALL RIGHTS RESERVED.6 Absorption Getting into the bloodstream pH Lipid (fat) solubility Presence or absence of food in the stomach

7. Copyright © 2007 by Thomson Delmar Learning. ALL RIGHTS RESERVED.7 Distribution Moving from the bloodstream into the tissues and fluids Blood-brain barrier Placental barrier Selective distribution

8. Copyright © 2007 by Thomson Delmar Learning. ALL RIGHTS RESERVED.8 Metabolism Physical and chemical alterations that a substance undergoes in the body Biotransformation (liver) Effects of hepatic disease

9. Copyright © 2007 by Thomson Delmar Learning. ALL RIGHTS RESERVED.9 Excretion Eliminating waste products of metabolized drug Kidney function Cumulative effect Toxicity

10. Copyright © 2007 by Thomson Delmar Learning. ALL RIGHTS RESERVED.10 Other Variables for distibution Age Weight Sex

11. Copyright © 2007 by Thomson Delmar Learning. ALL RIGHTS RESERVED.11 Other Variables Psychological state –Placebo effect –Use of placebos in research –Cultural and religious beliefs –Attitude of health care worker

12. Copyright © 2007 by Thomson Delmar Learning. ALL RIGHTS RESERVED.12 Dosage Amount of drug needed for a therapeutic or desired effect Minimum dose Maximum dose Loading dose Maintenance dose

13. Copyright © 2007 by Thomson Delmar Learning. ALL RIGHTS RESERVED.13 Dosage Toxic dose Lethal dose Therapeutic dose

14. Copyright © 2007 by Thomson Delmar Learning. ALL RIGHTS RESERVED.14 Route GI tract –Oral (PO) –Nasogastric tube (NG) –Rectal (R)

15. Copyright © 2007 by Thomson Delmar Learning. ALL RIGHTS RESERVED.15 Route Parenteral –Sublingual (SL) –Injection –Topical –Inhalation

16. Copyright © 2007 by Thomson Delmar Learning. ALL RIGHTS RESERVED.16 Unexpected Responses Adverse drug effects –Teratogenic –Idiosyncrasy –Tolerance –Dependence –Hypersensitivity –Anaphylactic reaction