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
Vd = 0.25 L/kgC = 8 mg/LLD = ?55 kg

Practice exercise (made-up values, not clinical guidance). A patient who weighs 55 kg needs a loading dose of gentamicin to reach a level of 8 mg/L straight away. The volume of distribution is 0.25 L/kg. Find the loading dose LD in mg.

55 kgVd = 0.25 L/kgC = 8 mg/L
LD = mg
2.Easy
t/t½C/Css (%)100%3.5f = ?

Practice exercise (made-up values, not clinical guidance). A patient receives vancomycin as a constant IV infusion without a loading dose. The half-life is 12 h. What percentage f of the steady-state level has been reached after 42 h?

t½ = 12 ht = 42 h
f = %
3.Medium
110100t (h)C (mg/L)1 h9 mg/L5 h3 mg/L

Practice exercise (made-up values, not clinical guidance). After an IV dose of gentamicin, the level is 9 mg/L at 1 h and 3 mg/L at 5 h. Assume first-order elimination. Find the half-life t½.

C1 = 9 mg/L (1 h)C2 = 3 mg/L (5 h)
t½ = h
4.Medium
110t (h)C (mg/L)1 h7 mg/L5 h1.8 mg/L

Practice exercise (made-up values, not clinical guidance). After an IV dose of gentamicin, the level is 7 mg/L at 1 h and 1.8 mg/L at 5 h. Assume first-order elimination. Find the half-life t½.

C1 = 7 mg/L (1 h)C2 = 1.8 mg/L (5 h)
t½ = h
5.Hard
69 kg53 · womanSCr 2.1 mg/dLCrCl → τ = ? h

Practice exercise (made-up values, not clinical guidance). A 53-year-old woman weighs 69 kg and has a serum creatinine of 2.1 mg/dL (186 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 tobramycin regimen is 120 mg every 8 h for a creatinine clearance of 120 mL/min. Keeping the dose, the interval is lengthened in proportion to the fall in clearance. Find the new dosing interval τ. Round to one decimal place.

53 years69 kgwomanSCr = 2.1 mg/dL120 mg q8hCrCl normal 120 mL/min
τ = h
6.Hard
VCss,avg​ = ?200 mg · q12hCL = 0.05 L/kg/h78 kg · S = 1 · F = 1

Practice exercise (made-up values, not clinical guidance). A 78 kg patient takes oral theophylline (F = 1) every 12 h. The clearance is 0.05 L/kg/h. Each dose is 200 mg of theophylline. Find the average steady-state level Css,avg.

CL = 0.05 L/kg/hτ = 12 hS = 1F = 178 kgD = 200 mg
Css,avg = mg/L

Answer key

  1. 1. LD = 110 mg
  2. 2. f = 91.16 %
  3. 3. t½ = 2.524 h
  4. 4. t½ = 2.041 h
  5. 5. τ = 28.4 h
  6. 6. Css,avg = 4.274 mg/L

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