Exam 1

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Exam 1
2012-02-06 00:54:19
BPharm PKin Baski

Baski's ramblings
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  1. How do you find k0 (the zero order elimination constant)?
    • C= -k0t + C0
    • where C is concentration at time t
    • where C0 is initial concentraion
    • where t is any time
  2. What does ln =?
  3. t1/2 = ?
  4. k = ?
  5. Define biopharmaceutics.
    BP analyzes the interrelationship among the physiochemical properties of the drug, the dosage form, the route of administration and the rate and extent of drug absorption into systemic circulation.
  6. Define pharmacokinetics.
    PK deals with the kinetics of absorption, distribution, metabolism, and excretion of drugs. What does the body do to the drug?
  7. Define pharmacodynamics.
    What does the drug do to the body?
  8. _______ can be either paracellular or transcellular?
    passive transport
  9. What is the degree of ionization controlled by? (3 things)
    • pKa
    • pH of surrounding aqueous phase
    • whether the drug is a weak acid or a weak base
  10. What is typical pH of stomach?
  11. What are the factors that affect oral absorption?
    • disintegration of dosage form
    • dissolution of particles
    • chemical stability of drug
    • stability of drug to enzymes
    • motility and mixing in GI tract
    • presence and type of food
    • blood flow to GI tract
    • gastric emptying time
    • formulation
  12. Define biopharmaceutics.
    the study of the physical and chemical properties of drugs and their proper dosage as related to the onset, duration, and intensity of drug action under physiological or pathophysiological conditions
  13. Define MRT (mean residence time).
    the average total time molecules of a given dose spend in the body
  14. Define AUMC. (area under the moment curve)
    integral of product of time and plasma concentration
  15. Define tmax.
    • the time after administration of drug at which Cmax is observed
    • measure of the rate of absorption
  16. Define Cmax.
    • the observed maximum concentration of drug
    • measure of both the rate of absorption and the extent of drug available in systemic circulation
  17. Define AUC.
    • area under the concentration-time curve
    • measure of the extent of drug available in systemic circulation
  18. What is polymorphism?
    the existence of a substance in more than one crystalline form
  19. What is the order for dissolution rate of polymorphs?
  20. Which has more energy, stable polymorph or metastable?
  21. Define porosity.
    measure of void spaces
  22. What does the angle of repose measure?
  23. What is the rate limiting step of absorption?
  24. What is the biggest factor that contributes to delay in drug absorption in the body?
  25. What are the 3 theories of drug dissolution?
    • 1. Film Theory
    • 2. Danckwert's model
    • 3. Interfacial Barrier model
  26. Define partition coefficient.
    • the ratio of distribution of a solute between the 2 phases of 2 immiscible liquids that are in contact with each other
    • (water and lipid)
  27. what is the active carrier process for cations and anions in the kidney?
    tubular secretion
  28. What is the first step in renal drug excretion?
    glomerular filtration
  29. What MW are drugs that are excreted into the bile?
  30. What factors affect t1/2?
    • drug clearance rate
    • Vd
    • disease or age
  31. Cl=
    Vd x ke
  32. Vd =
  33. Cl =
  34. k =
    (lnC1 - lnC2)/(t2-t1)
  35. AUC=
  36. Cinitial=
  37. ____ is independent of the concentration of drug in the plasma?
    zero order
  38. In ____ _____ kinetics, the rate of elimination is constant?
    zero order
  39. In _____ ______ kinetics, the clearance is inversely proportional to the drug concentration?
    zero order
  40. In ____ ______ kinetics, t1/2 is directly proportional to drug concentration in plasma?
    zero order
  41. What are the phase 1 reactions?
    • hydroxylation
    • oxidation
    • N-dealkylation
    • oxidative deamination
  42. What is a phase 2 reaction?
    • a conjugation with glucuronide or sulphate
    • it alters the activity and makes it less lipid soluble (more water soluble) so it can be excreted
  43. What are some factors that affect biotransformation (metabolism)?
    • race
    • age
    • gender
    • disease state
    • other drugs
    • food
    • species
    • first pass effect
  44. What are some drugs that have a low therapeutic index?
    • digoxin
    • warfarin
    • phenytoin
    • lithium
  45. How can you increase dissolution rate of a drug?
    • reduce particle size
    • increase lipophillicity (add a surfactant)
    • add an ion exchange resin
    • porous microparticle technology(HDDS)
    • hydrophillic solubilization technology(HST)
    • controlled precipitation technology
    • inclusion complexes
    • solid dispersion
  46. Absolute bioavailability refers to what ROA?
  47. Relative bioavailability relates to what ROA?
    anything but IV
  48. Which method can be done in vivo-- pharmacodynamic or pharmacokinetic?
  49. Slope = m =
    • mx + b
    • Y2- Y1/X2-X1
  50. 2.3 x slope =
  51. 2.3logN=?
  52. 1 dL =
    100 ml
  53. Varea =
    Dose/(beta x AUC) = Cl/beta
  54. alpha x beta (A+B)/Abeta + Balpha =
  55. AB (beta-alpha)2/(A+B)(Abeta+Balpha)=
  56. Abeta + Balpha/A+B=
  57. What are the units for AUC?
  58. beta is ?
  59. alpha is ?
  60. B=?
    y intercept of beta line
  61. A=?
    y intercept of alpha line
  62. Vss =
  63. Vi=?
  64. Varea=?
    Dose/beta x AUC= Cl/beta
  65. To calculate drug concentration at any time for a two-compartment model use:
    C= Ae-alpha(t) + Be-beta(t)