Saudi Prometric Nursing Pharmacology and Drug Calculations

Question 1

A patient weighing 70 kg is prescribed gentamicin 5 mg/kg IV once daily. What is the correct dose?

Accepted Answer

350 mg

Answer

Dose = weight (kg) × dose/kg = 70 kg × 5 mg/kg = 350 mg. Weight-based dosing of aminoglycosides like gentamicin is standard practice to optimize therapeutic efficacy while minimizing nephrotoxicity and ototoxicity.

Question 2

A nurse is preparing to administer heparin 5,000 units subcutaneously. The available vial contains 10,000 units/mL. How many mL should be administered?

Accepted Answer

0.5 mL

Answer

Volume = desired dose / available concentration = 5,000 units / 10,000 units per mL = 0.5 mL. This is a standard dosage calculation using the ratio method or the formula D/H × V.

Question 3

A patient is prescribed morphine 4 mg IV. The available solution contains 10 mg in 5 mL. How many mL should the nurse administer?

Accepted Answer

2 mL

Answer

Concentration = 10 mg/5 mL = 2 mg/mL. Volume = 4 mg ÷ 2 mg/mL = 2 mL. Alternatively: (4 mg / 10 mg) × 5 mL = 2 mL.

Question 4

A nurse is administering an IV infusion of 1,000 mL normal saline over 8 hours. Using a drip set of 20 drops/mL, what is the correct drip rate in drops per minute (dpm)?

Accepted Answer

42 dpm

Answer

Drip rate = (Volume in mL × Drop factor) / Time in minutes = (1,000 × 20) / (8 × 60) = 20,000 / 480 = 41.67 ≈ 42 dpm. This standard formula calculates gravity IV infusion rates.

Question 5

A patient is prescribed dopamine 400 mg in 250 mL D5W to infuse at 5 mcg/kg/min. The patient weighs 80 kg. What is the infusion rate in mL/hr?

Accepted Answer

15 mL/hr

Answer

Step 1: Dose in mcg/min = 5 × 80 = 400 mcg/min. Step 2: Convert to mg/min: 400/1,000 = 0.4 mg/min. Step 3: Concentration = 400 mg/250 mL = 1.6 mg/mL. Step 4: mL/min = 0.4/1.6 = 0.25 mL/min. Step 5: mL/hr = 0.25 × 60 = 15 mL/hr.

Saudi Prometric Nursing Practice Test

Saudi Prometric Nursing Practice Test

Saudi Prometric Nursing Pharmacology and Drug Calculations