Clinical pharmacokinetics worksheet with answers

Free printable Clinical pharmacokinetics worksheet: 6 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

New worksheetPractise online with hints

For teachers: free to print, copy and use in class. Every new worksheet has new values and its own answer key. A link to ExamProblems on your course page is appreciated.

Name: ____________________   Date: ____________

1.Easy
110100t (h)CC₀t½ = 2.5 hC₀/2

Practice exercise (made-up values, not clinical guidance). In a patient, tobramycin has an elimination half-life of 2.5 h. Find the elimination rate constant k in h⁻¹.

t½ = 2.5 h
k = h⁻¹
2.Easy
Vd = 0.25 L/kgC = 6 mg/LLD = ?50 kg

Practice exercise (made-up values, not clinical guidance). A patient who weighs 50 kg needs a loading dose of gentamicin to reach a level of 6 mg/L straight away. The volume of distribution is 0.25 L/kg. Find the loading dose LD in mg.

50 kgVd = 0.25 L/kgC = 6 mg/L
LD = mg
3.Medium
Vd = 7 L/kgC = 0.8 mcg/LLD = ? mcg58 kg · S = 1 · F = 0.7

Practice exercise (made-up values, not clinical guidance). A 58 kg patient is to be loaded with digoxin tablets to reach a level of 0.8 mcg/L. The volume of distribution is 7 L/kg and the tablets have a bioavailability F = 0.7. Find the total oral loading dose LD in mcg.

58 kgVd = 7 L/kgC = 0.8 mcg/LF = 0.7
LD = mcg
4.Medium
110100t (h)C (mg/L)1 h10 mg/L6 h2.5 mg/L

Practice exercise (made-up values, not clinical guidance). After an IV dose of tobramycin, the level is 10 mg/L at 1 h and 2.5 mg/L at 6 h. Assume first-order elimination. Find the half-life t½.

C1 = 10 mg/L (1 h)C2 = 2.5 mg/L (6 h)
t½ = h
5.Hard
0.1110100t (h)C (mg/L)Cpeak​ = 10τ = ?Ctrough​ = 0.5

Practice exercise (made-up values, not clinical guidance). A patient's gentamicin half-life is 3 h. The target is a peak of 10 mg/L and a trough of 0.5 mg/L. Assuming rapid IV doses and first-order elimination, what dosing interval τ lets the level fall from the peak to the trough? Round to one decimal place.

t½ = 3 hCpeak = 10 mg/LCtrough = 0.5 mg/L
τ = h
6.Hard
85 kg73 · womanSCr 1.8 mg/dLCrCl → D = ? mg

Practice exercise (made-up values, not clinical guidance). A 73-year-old woman weighs 85 kg and has a serum creatinine of 1.8 mg/dL (159 µmol/L). Estimate the creatinine clearance with Cockcroft–Gault: CrCl (mL/min) = (140 − age) × weight (kg)/(72 × SCr in mg/dL), × 0.85 for women. The usual gentamicin dose is 120 mg every 8 h for a creatinine clearance of 100 mL/min. Keeping the interval, the dose is reduced in proportion to the creatinine clearance. Find the adjusted dose D. Round to the nearest whole number.

73 years85 kgwomanSCr = 1.8 mg/dL120 mg q8hCrCl normal 100 mL/min
D = mg

Answer key

  1. 1. k = 0.2773 h⁻¹
  2. 2. LD = 75 mg
  3. 3. LD = 464 mcg
  4. 4. t½ = 2.5 h
  5. 5. τ = 13 h
  6. 6. D = 45 mg

Full step-by-step solutions: practise this topic on examproblems.com.