Heparin and insulin calculations trip up many nursing students because these medications are dosed in units, not milligrams, and errors can be dangerous.
This free timed quiz includes 10 heparin and insulin dosage practice questions with answers and rationales, covering units/mL concentrations, pump rates in mL/hr, weight-based heparin boluses, and combining insulin doses.
The key move: find the concentration (units ÷ mL), then divide the ordered units/hr by that concentration to get the pump rate.
All 10 Questions With Answers & Rationales
Prefer to work at your own pace? Every question from the timed quiz above is listed here in full. Solve each on paper, then tap Show Answer & Rationale to check your work.
Question 1: Heparin
A heparin infusion is ordered at 1,000 units/hr. The bag contains 25,000 units in 500 mL of D5W. At what rate in mL/hr should the nurse set the pump?
- A. 25 mL/hr
- B. 20 mL/hr
- C. 50 mL/hr
- D. 10 mL/hr
Show Answer & Rationale
Answer: B. 20 mL/hr
Rationale: Concentration = 25,000 units ÷ 500 mL = 50 units/mL. Rate = 1,000 units/hr ÷ 50 units/mL = 20 mL/hr.
Question 2: Heparin
A heparin bag has 20,000 units in 500 mL. The pump is running at 30 mL/hr. How many units/hr is the client receiving?
- A. 600 units/hr
- B. 1,200 units/hr
- C. 1,500 units/hr
- D. 900 units/hr
Show Answer & Rationale
Answer: B. 1,200 units/hr
Rationale: Concentration = 20,000 units ÷ 500 mL = 40 units/mL. Units/hr = 40 units/mL × 30 mL/hr = 1,200 units/hr.
Question 3: Insulin
A vial of insulin is labeled 100 units/mL. The order is for 35 units. How many mL should the nurse draw up in an insulin syringe?
- A. 3.5 mL
- B. 0.035 mL
- C. 0.35 mL
- D. 35 mL
Show Answer & Rationale
Answer: C. 0.35 mL
Rationale: (35 units ÷ 100 units) × 1 mL = 0.35 mL. (In practice, insulin is measured directly on a unit-marked insulin syringe.)
Question 4: Heparin
A provider orders a heparin bolus of 80 units/kg for a client weighing 70 kg. How many units should the nurse administer?
- A. 560 units
- B. 8,000 units
- C. 5,600 units
- D. 1,600 units
Show Answer & Rationale
Answer: C. 5,600 units
Rationale: Bolus = 80 units/kg × 70 kg = 5,600 units.
Question 5: Units/min
A heparin drip is set to deliver 18 units/kg/hr for a 90 kg client. How many units/hr will the client receive?
- A. 162 units/hr
- B. 1,620 units/hr
- C. 1,800 units/hr
- D. 900 units/hr
Show Answer & Rationale
Answer: B. 1,620 units/hr
Rationale: Units/hr = 18 units/kg/hr × 90 kg = 1,620 units/hr.
Question 6: Insulin
An order reads: regular insulin 12 units and NPH insulin 28 units subcutaneously. What is the total number of units the nurse draws into one syringe?
- A. 16 units
- B. 24 units
- C. 40 units
- D. 30 units
Show Answer & Rationale
Answer: C. 40 units
Rationale: Total = 12 units + 28 units = 40 units. Draw up the regular (clear) insulin first, then NPH (cloudy).
Question 7: Heparin
A heparin infusion contains 25,000 units in 250 mL. The order is 800 units/hr. What is the correct pump rate in mL/hr?
- A. 16 mL/hr
- B. 8 mL/hr
- C. 10 mL/hr
- D. 4 mL/hr
Show Answer & Rationale
Answer: B. 8 mL/hr
Rationale: Concentration = 25,000 units ÷ 250 mL = 100 units/mL. Rate = 800 units/hr ÷ 100 units/mL = 8 mL/hr.
Question 8: Insulin Drip
An insulin drip has 100 units in 100 mL of normal saline. The order is 6 units/hr. At what rate in mL/hr should the pump be set?
- A. 3 mL/hr
- B. 12 mL/hr
- C. 6 mL/hr
- D. 10 mL/hr
Show Answer & Rationale
Answer: C. 6 mL/hr
Rationale: Concentration = 100 units ÷ 100 mL = 1 unit/mL. Rate = 6 units/hr ÷ 1 unit/mL = 6 mL/hr.
Question 9: Heparin
A client on a heparin drip weighs 80 kg. The protocol calls for a rate increase of 2 units/kg/hr. By how many units/hr should the infusion be increased?
- A. 16 units/hr
- B. 80 units/hr
- C. 160 units/hr
- D. 200 units/hr
Show Answer & Rationale
Answer: C. 160 units/hr
Rationale: Increase = 2 units/kg/hr × 80 kg = 160 units/hr.
Question 10: Insulin
An insulin vial contains 100 units/mL. The order is 22 units. Using a tuberculin syringe (mL), how many mL equals this dose?
- A. 2.2 mL
- B. 0.022 mL
- C. 0.44 mL
- D. 0.22 mL
Show Answer & Rationale
Answer: D. 0.22 mL
Rationale: (22 units ÷ 100 units) × 1 mL = 0.22 mL. An insulin syringe is preferred, but this shows the mL equivalent.
NCLEX Dosage Calculation Practice Tests
Master the medication math that shows up most on the NCLEX with 135 free, timed dosage questions — complete with answers and step-by-step rationales. Work through all twelve tests to build speed and confidence.
Dosage Calculations Practice Questions
Our original 25-item mixed practice set covering the core dosage calculations every nursing student needs to know.
IV Flow Rates
Drops per minute, mL/hr pump settings, and drop-factor calculations for IV infusions.
Pediatric & Weight-Based Dosing
mg/kg calculations, safe-dose range checks, and body-weight dosing for pediatric clients.
Heparin, Insulin & Units
High-alert unit-based math — heparin drips, insulin dosing, and weight-based bolus calculations.
Oral Meds & Unit Conversions
Tablets, oral suspensions, and metric conversions including g, mg, mcg, tsp, mL, and lb-to-kg.
Basic Dosage & Conversions
Tablets, oral liquids, and metric/household unit conversions — the foundation of safe medication math.
IV Titration (mcg/kg/min, mg/hr)
Vasoactive and sedation drips: mcg/kg/min, mcg/min and mg/hr to mL/hr, working back from the pump, and titration steps.
Reconstitution
Mixing powdered medications: diluent volume vs. final concentration, multi-strength vial tables, labeling, and doses per vial.
Safe-Dose Range
Is the prescribed dose safe? mg/kg/day vs. mg/kg/dose ranges, maximum-dose caps, unit conversions, and what to do when a dose is too high or too low.
IV Drip Rates & Infusion Times
When will the bag finish? Infusion end times, time left in a bag, counting drops on a gravity line, shift and 24-hour IV totals, and IVs that fall behind.
Pediatric BSA & Weight-Based Dosing
Body surface area with the Mosteller formula, mg/m² doses, BSA safe-dose checks, mL/kg boluses, maintenance fluid rates, and mg/kg/hr infusions for children.
Mixed Review
Every skill in the series mixed together: IM doses, heparin and insulin drips, lb-to-kg, mEq, percent solutions, g/hr infusions, pediatric liquids, gravity drips, and safe dose writing.
