DBB - Exam 1 - Principles of Pharmacology (Ch. 1)

  1. Specific drug effects vs. Non-specific drug effects
    • Specific drug effects: effects based on the physical and biochemical interactions of a drug with a target site in living tissue
    • Nonspecific drug effects: those that are not based on the chemical activity of a drug-receptor interaction but on certain unique characteristics of the individual
  2. Therapeutic effects
    The intended/desired physical/behavioral effects
  3. Side effects
    Unintended drug effects that may be mild or may be dangerous
  4. Drug action vs. drug effect
    • Drug action: the specific molecular changes produced by a drug when it binds to a particular target site/receptor
    • Drug effects: more widespread alterations in physiological or psychological functions; not necessarily in the same site as the drug action
  5. Placebo and double-blind experiments
    You know this
  6. Bioavailability
    Concentration of a drug in the blood that is free to bind at specific target sites
  7. Pharmacokinetics
    • Factors that contribute to the administration, absorption, distribution, binding, inactivation, and excretion of a drug
    • How the body reacts to the drug
  8. How the body reacts to the drug
  9. Pharmacodynamics
    • Study of the physiological and biochemical interactions of a drug with the target tissue responsible for the drug's effects
    • What the drug does to the body; includes the drug's mechanism of action
  10. What the drug does to the body
  11. 4 factors of pharmacokinetics (according to lecture):
    • Absorption
    • Distribution
    • Metabolism
    • Elimination
  12. 5 factors of pharmacokinetics (according to book):
    • Routes of administration
    • Absorption and distribution
    • Binding
    • Inactivation
    • Excretion
  13. Drug inactivation
  14. Methods of drug administration
    • Oral (PO)
    • Intravenous (IV)
    • Intramuscular (IM)
    • Subcutaneous (SC)
    • Inhalation
    • Topical
    • Transdermal (skin patches)
    • Epidural (directly into CSF)
  15. First-pass metabolism
    When the liver metabolized some of a drug before it can circulate through the body; occurs particularly with orally administered drugs
  16. Advantages/disadvantages or oral administration:
    • Advantages: safe; self-administered; economical; no needle-related complications
    • Disadvantages: slow and variable absorption; subject to first-pass metabolism; less predictable blood levels
  17. Advantages/disadvantages of IV administration:
    • A: Most rapid; most accurate blood concentration
    • D: Overdose danger; cannot be readily reversed; requires sterile needles and medical technique
  18. Adv./Disadv. of IM administration:
    • A: slow and even absorption
    • D: localized irritation at injection site; needs sterile equipment
  19. Adv./Disadv. of SC administration:
    • A: Slow and prolonged absorption
    • D: Variable absorption depending on blood flow
  20. Adv./Disadv. of inhalation:
    • A: Large absorption surface; rapid onset; no injection equipment
    • D: Irritation of nasal passages; small inhaled particles may damage lungs
  21. Adv./Disadv. of topical administration:
    • A: Localized actions and effects; easy self-administration
    • D: May be absorbed into general circulation
  22. Adv./Disadv. of transdermal administration:
    • A: Controlled and prolonged absorption
    • D: Local irritation; useful only for lipid soluble drugs
  23. Adv./Disadv. of epidural administration
    • A: Bypasses blood-brain barrier; rapid effect in CNS
    • D: Not reversible; needs trained anesthesiologist; possible nerve damage
  24. Drug depots
    Inactive sites where drugs accumulate
  25. Depot binding
    The binding of a drug to inactive sites; it is reversible
  26. First-order kinetics
    Exponential elimination of drugs from the bloodstream
  27. Zero-order kinetics
    Constant, linear rate of drug removal from the body, regardless of drug concentration in blood
  28. Half-life
    The amount of time required for removal of 50% of a drug
  29. Phase I biotransformation reactions
    • Frequently carried out through the P450 system
    • Nonsynthetic modification
    • Often is oxidation (usually by addition of a hydroxyl)
  30. Phase II biotransformation reactions
    • Synthetic reactions
    • Combination (conjugation) with some molecule such asĀ glucuronide, sulfate, or methyl groups
  31. Phase I and phase II reactions of phenobarbital, aspirin, morphine, and diazepam
    • Phernobarbital -----> Hydroxyphenobarbital (phase I)
    • Asprin ---(I)----> Salicylic acid ----(II)----> Salicyclic glucuronide
    • Morphine ----(II)----> Morphine-6-glucuronide
    • Diazepam ---(I)---> Desmethyldiazepam ---(I)---> Oxazepam ---(II)---> Oxazepam-glucuronide
  32. P450 Induction/Inhibition
    • Induction ---> More P450; increased rate of biotransformation; lower blood level; reduced biological effect
    • Inhibition ---> Less P450; less biotransformation; higher blood level; larger biological effect
  33. ED50
    • 50% effective dose
    • The dose that produces half the maximum response
  34. TD50
    • 50% toxic dose
    • The dose at which 50% of the population experience a particular toxic effect
  35. Therapeutic index
    TD50 / ED50
  36. Additive effects vs. Potentiation in drug interactions
    • Additive effects: two drugs interact and the outcome equals the sum of the two individual effects
    • Potentiation: two drugs interact and it produces effects that are greater than the sum of the two individual effects
  37. Pharmacokinetic steady state
    When the intake of a drug is in equlibrium with its elimination
  38. How many half-lives does it typically take to reach steady state?
    4-5 half-lives
  39. Volume of distribution
    • The volume a drug would have to occupy to provide the same concentration as it currently is in blood plasma
    • Higher VOD = more drug stored in fat and tissue rather than blood = lower concentration in blood
  40. Clearance
    • The volume of plasma that is cleared of a drug per unit time
    • Includes direct excretion as well as biotransformation
  41. Half life equation:
    Half life is proportional to VOD/clearance
  42. Steady state concentration equation:
    • SS concentration = F x (dose/time)(1/clearance)
    • F is a constant
  43. When you age, what happens to clearance and VOD?
    Clearance decreases and VOD increases
Card Set
DBB - Exam 1 - Principles of Pharmacology (Ch. 1)