D441 Medical Dosage Calculations and
Pharmacology Study Guide - Pre-Nursing
Success 180-Question Comprehensive
Practice Exam
SECTION 1: DOSAGE CALCULATIONS – TABLETS & CAPSULES
Q1. A patient is prescribed 500 mg of a medication. The available
tablets are 250 mg each. How many tablets will you administer?
A) 1 tablet
B) 1.5 tablets
C) 2 tablets
D) 2.5 tablets
Correct Answer: C) 2 tablets
Rationale: Use the formula: Desired / Have × Quantity. 500 mg / 250 mg ×
1 tablet = 2 tablets.
,Q2. The physician orders 0.5 L of Normal Saline to infuse over 4 hours.
The drop factor is 15 gtt/mL. What is the flow rate in drops per
minute?
A) 31 gtt/min
B) 125 gtt/min
C) 15 gtt/min
D) 45 gtt/min
Correct Answer: A) 31 gtt/min
Rationale: Convert 0.5 L to 500 mL. Calculate mL/hr: 500 mL / 4 hrs = 125
mL/hr. Convert to gtt/min: (125 mL × 15 gtt/mL) / 60 min = 31.25 gtt/min
(rounded to 31).
Q3. A patient is on a continuous heparin drip at 18 mL/hr. The
concentration is 25,000 units in 500 mL of D5W. How many units per
hour is the patient receiving?
A) 900 units/hr
B) 1000 units/hr
C) 450 units/hr
D) 1800 units/hr
Correct Answer: A) 900 units/hr
,Rationale: Determine concentration: 25,000 units / 500 mL = 50 units/mL.
Multiply by rate: 50 units/mL × 18 mL/hr = 900 units/hr.
Q4. The nurse is to administer 40 mEq of Potassium Chloride (KCl). The
pharmacy sends a vial labeled "KCl 20 mEq/10 mL." How many mL will
the nurse administer?
A) 5 mL
B) 10 mL
C) 20 mL
D) 40 mL
Correct Answer: C) 20 mL
Rationale: Desired/Have × Quantity. 40 mEq / 20 mEq × 10 mL = 20 mL.
Q5. A child weighs 44 lbs. The ordered dose is 2 mg/kg/dose. What is
the single dose for this child?
A) 20 mg
B) 40 mg
C) 88 mg
D) 44 mg
, Correct Answer: B) 40 mg
Rationale: Convert lbs to kg: 44 lbs / 2.2 = 20 kg. Calculate dose: 2 mg/kg
× 20 kg = 40 mg.
Q6. The order reads 1000 mL D5W over 8 hours. The IV tubing has a
drop factor of 20 gtt/mL. Calculate the flow rate in gtt/min.
A) 42 gtt/min
B) 125 gtt/min
C) 250 gtt/min
D) 83 gtt/min
Correct Answer: A) 42 gtt/min
Rationale: mL/hr: 1000 mL / 8 hrs = 125 mL/hr. gtt/min: (125 mL × 20
gtt/mL) / 60 min = 41.66 ≈ 42 gtt/min.
Q7. A patient is prescribed 0.25 mg of a medication. The available
tablets are 0.125 mg each. How many tablets will you administer?
A) 1 tablet
B) 1.5 tablets
C) 2 tablets
D) 2.5 tablets
Pharmacology Study Guide - Pre-Nursing
Success 180-Question Comprehensive
Practice Exam
SECTION 1: DOSAGE CALCULATIONS – TABLETS & CAPSULES
Q1. A patient is prescribed 500 mg of a medication. The available
tablets are 250 mg each. How many tablets will you administer?
A) 1 tablet
B) 1.5 tablets
C) 2 tablets
D) 2.5 tablets
Correct Answer: C) 2 tablets
Rationale: Use the formula: Desired / Have × Quantity. 500 mg / 250 mg ×
1 tablet = 2 tablets.
,Q2. The physician orders 0.5 L of Normal Saline to infuse over 4 hours.
The drop factor is 15 gtt/mL. What is the flow rate in drops per
minute?
A) 31 gtt/min
B) 125 gtt/min
C) 15 gtt/min
D) 45 gtt/min
Correct Answer: A) 31 gtt/min
Rationale: Convert 0.5 L to 500 mL. Calculate mL/hr: 500 mL / 4 hrs = 125
mL/hr. Convert to gtt/min: (125 mL × 15 gtt/mL) / 60 min = 31.25 gtt/min
(rounded to 31).
Q3. A patient is on a continuous heparin drip at 18 mL/hr. The
concentration is 25,000 units in 500 mL of D5W. How many units per
hour is the patient receiving?
A) 900 units/hr
B) 1000 units/hr
C) 450 units/hr
D) 1800 units/hr
Correct Answer: A) 900 units/hr
,Rationale: Determine concentration: 25,000 units / 500 mL = 50 units/mL.
Multiply by rate: 50 units/mL × 18 mL/hr = 900 units/hr.
Q4. The nurse is to administer 40 mEq of Potassium Chloride (KCl). The
pharmacy sends a vial labeled "KCl 20 mEq/10 mL." How many mL will
the nurse administer?
A) 5 mL
B) 10 mL
C) 20 mL
D) 40 mL
Correct Answer: C) 20 mL
Rationale: Desired/Have × Quantity. 40 mEq / 20 mEq × 10 mL = 20 mL.
Q5. A child weighs 44 lbs. The ordered dose is 2 mg/kg/dose. What is
the single dose for this child?
A) 20 mg
B) 40 mg
C) 88 mg
D) 44 mg
, Correct Answer: B) 40 mg
Rationale: Convert lbs to kg: 44 lbs / 2.2 = 20 kg. Calculate dose: 2 mg/kg
× 20 kg = 40 mg.
Q6. The order reads 1000 mL D5W over 8 hours. The IV tubing has a
drop factor of 20 gtt/mL. Calculate the flow rate in gtt/min.
A) 42 gtt/min
B) 125 gtt/min
C) 250 gtt/min
D) 83 gtt/min
Correct Answer: A) 42 gtt/min
Rationale: mL/hr: 1000 mL / 8 hrs = 125 mL/hr. gtt/min: (125 mL × 20
gtt/mL) / 60 min = 41.66 ≈ 42 gtt/min.
Q7. A patient is prescribed 0.25 mg of a medication. The available
tablets are 0.125 mg each. How many tablets will you administer?
A) 1 tablet
B) 1.5 tablets
C) 2 tablets
D) 2.5 tablets
