Q 1.1 A linear graph of Cp versus time for three different dosage forms (A, B, and C). A and B have the same extent of absorption and rate of absorption whereas C has a slower absorption but similar extent of absorption
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Q 1.2 A linear plot of Cp versus time (for 72 hr) after three equal oral doses given at 0, 24, and 48 hours.
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Q 1.3 A linear Dettli plot with fe = 0.33.
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Q 1.4 A Scatchard plot representing 1:1 drug protein binding with one type of binding site. (Note: This question refers to material in Chapter 18)
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Q 2.2 The average plasma concentration calculated at steady state after a large number of uniform oral doses given with uniform dosing intervals is independent of the absorption rate constant. True False
Q 2.3 Elimination of salicylate (a weak acid) is faster when the urine pH is 4.5 compared with when the urine pH is 8.5. True False
Q 2.4 Phase II metabolism processes commonly result in metabolites that have a smaller molecular weight than the parent drug. True False
Q 2.5 Increasing the amount or percentage of lubricant in a table formulation will generally increase the dissolution rate of the drug because of the penetrating capacity of these ingredients. True False
Q 2.6 Drugs that are extensively distributed into specific tissue regions, such as chloroquine into the liver, tend to have quite small values for the apparent volume of distribution. (Note: This question refers to material in Chapter 18) True False
Q 2.7 When the total intrinsic liver clearance of a drug is quite high compared with liver blood flow it may be said that the drug has flow limited clearance. True False
Q 2.8 When developing a multiple dose regimen, doubling both the dosing interval and the dose will result in the same average plasma concentration. True False
Q 2.9 With just oral data it is not possible to determine separate values of V and F. True False
Q 2.10 Increasing the number of particles that make up a certain weight of drug will slow down the overall dissolution process because there are more particles to go into solution. True False
Q 3.1 Briefly describe the intramuscular route of administration, giving advantages and disadvantages of the method.
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Q 3.2 Briefly describe the parameter clearance, providing a definition, an equation suitable for estimating this parameter, and units.
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Q 3.3 Briefly describe the parameters of Fick's first law as they relate to drug dissolution.
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Q 4.1 (16 points) Calculate a suitable dosage regimen for an 85 kg patient who is to be given drug X to achieve an average plasma concentration of 8 µg/ml. The apparent volume of distribution for this drug is 1.9 L/kg and the half-life is 19 hours. The oral bioavailability is 75%. Calculate a once-a-day oral dose. Tablets are available containing 25, 100, and 250 mg. What would be a suitable regimen. Calculate average and minimum concentrations for your 'suitable' regimen.
Q 4.2 (19 points) Calculate a suitable dosage regimen (MD and LD) for a 56 year old, 79 kg male patient with a serum creatinine of 1.8 mg/100 ml who requires a gentamicin peak close to but below 8 mg/L and a trough below 1 mg/L. [Use kel = 0.021 + (0.00275*Clcr) hr-1 and V = 0.21 L/kg]. Choose suitable rounded doses (nearest 10 mg) and a suitable interval. Check your final regimen.
Q 4.3 (14 points) The following data were collected after the oral administration (200 mg) of a drug. Calculate ka, kel, and V/F using the method of residuals. Assume ka > kel. (2 - cycle semi-log graph paper provided)
Data Obtained After 200 mg Oral Administration
| Time hr | Concentration mg/L | <-----> | <-----> | <-----> |
| 0.25 | 4.5 | |||
| 0.5 | 7.3 | |||
| 1 | 9.8 | |||
| 1.5 | 10.4 | |||
| 4 | 7.7 | |||
| 9 | 3.9 | |||
| 14 | 1.8 |