HESI Dosage Calculation 2025
Question 1: Oral medication Dosage
Order: Administer 500 mg of acetaminophen.
Available: Acetaminophen 250 mg per tablet.
How many tablets will you administer?
Answer:
Dose OrderedDose Available=500 mg250 mg/tab=2 tablets\frac{\text{Dose
Ordered}}{\text{Dose Available}} = \frac{500 \, \text{mg}}{250 \, \text{mg/tab}} =
2 \, \text{tablets}Dose AvailableDose Ordered=250mg/tab500mg=2tablets
,Question 2: IV Flow Rate (mL/hr)
Order: Infuse 1,000 mL of normal saline over 8 hours.
What is the flow rate in mL/hr?
Answer:
Total Volume (mL)Time (hr)=1,000 mL8 hr=125 mL/hr\frac{\text{Total Volume
(mL)}}{\text{Time (hr)}} = \frac{1,000 \, \text{mL}}{8 \, \text{hr}} = 125 \, \
text{mL/hr}Time (hr)Total Volume (mL)=8hr1,000mL=125mL/hr
Question 3: Pediatric Dosage
Order: Administer amoxicillin 90 mg/kg/day in 2 divided doses.
The child weighs 15 kg. How much medication will you administer per dose?
Answer:
1. Calculate the total daily dose:
90 mg/kg/day×15 kg=1,350 mg/day90 \, \text{mg/kg/day} \times 15 \, \
text{kg} = 1,350 \, \text{mg/day}90mg/kg/day×15kg=1,350mg/day
2. Divide the total daily dose by 2:
1,350 mg2=675 mg/dose\frac{1,350 \, \text{mg}}{2} = 675 \,
\text{mg/dose}21,350mg=675mg/dose
Question 4: Weight-Based IV Medication
Order: Administer dopamine at 5 mcg/kg/min.
Patient's weight: 70 kg.
Dopamine is available as 400 mg in 250 mL of D5W.
What is the IV flow rate in mL/hr?
Answer:
, 1. Calculate the dose in mcg/min:
5 mcg/kg/min×70 kg=350 mcg/min5 \, \text{mcg/kg/min} \times 70 \, \
text{kg} = 350 \, \text{mcg/min}5mcg/kg/min×70kg=350mcg/min
2. Convert mcg to mg:
350 mcg1,000=0.35 mg/min\frac{350 \, \text{mcg}}{1,000} = 0.35 \, \
text{mg/min}1,000350mcg=0.35mg/min
3. Find the concentration of dopamine in the IV bag:
400 mg250 mL=1.6 mg/mL\frac{400 \, \text{mg}}{250 \, \text{mL}} = 1.6 \, \
text{mg/mL}250mL400mg=1.6mg/mL
4. Calculate flow rate in mL/min:
0.35 mg/min1.6 mg/mL=0.21875 mL/min\frac{0.35 \, \text{mg/min}}{1.6 \, \
text{mg/mL}} = 0.21875 \, \text{mL/min}1.6mg/mL0.35mg/min
=0.21875mL/min
5. Convert to mL/hr:
0.21875 mL/min×60 min/hr=13.125 mL/hr0.21875 \, \text{mL/min} \times 60
\, \text{min/hr} = 13.125 \,
\text{mL/hr}0.21875mL/min×60min/hr=13.125mL/hr
Rounded: 13.1 mL/hr
Question 5: Reconstitution of Powdered Medication
Order: Administer 500 mg of ceftriaxone IM.
Available: Vial labeled 1 g with instructions to reconstitute with 3.6 mL of diluent to
yield a concentration of 250 mg/mL.
How many mL will you administer?
Answer:
1. Determine the volume per mg:
250 mg1 mL=250 mg/mL\frac{\text{250 mg}}{\text{1 mL}} = 250 \, \
text{mg/mL}1 mL250 mg=250mg/mL
, 2. Calculate the volume needed for 500 mg:
500 mg250 mg/mL=2 mL\frac{500 \, \text{mg}}{250 \, \text{mg/mL}} = 2 \, \
text{mL}250mg/mL500mg=2mL
Question 6: Insulin Administration
Order: Administer 12 units of regular insulin and 20 units of NPH insulin
subcutaneously.
How many total units of insulin will you draw into the syringe?
Answer:
12 units (regular) + 20 units (NPH) = 32 units total
Question 7: Drop Factor (gtt/min)
Order: Infuse 1,000 mL over 12 hours using tubing with a drop factor of 15 gtt/mL.
What is the drip rate in gtt/min?
Answer:
1. Calculate flow rate in mL/min:
1,000 mL12 hr×60 min/hr=1.39 mL/min\frac{1,000 \, \text{mL}}{12 \, \
text{hr} \times 60 \, \text{min/hr}} = 1.39 \,
\text{mL/min}12hr×60min/hr1,000mL=1.39mL/min
2. Multiply by drop factor:
1.39 mL/min×15 gtt/mL=20.8 gtt/min1.39 \, \text{mL/min} \times 15 \, \
text{gtt/mL} = 20.8 \, \text{gtt/min}1.39mL/min×15gtt/mL=20.8gtt/min
Rounded: 21 gtt/min
Question 8: Dilution of IV Medication
Order: Administer 250 mg of vancomycin IV over 2 hours.
Available: Vial labeled 500 mg of vancomycin, to be reconstituted with 10 mL of
Question 1: Oral medication Dosage
Order: Administer 500 mg of acetaminophen.
Available: Acetaminophen 250 mg per tablet.
How many tablets will you administer?
Answer:
Dose OrderedDose Available=500 mg250 mg/tab=2 tablets\frac{\text{Dose
Ordered}}{\text{Dose Available}} = \frac{500 \, \text{mg}}{250 \, \text{mg/tab}} =
2 \, \text{tablets}Dose AvailableDose Ordered=250mg/tab500mg=2tablets
,Question 2: IV Flow Rate (mL/hr)
Order: Infuse 1,000 mL of normal saline over 8 hours.
What is the flow rate in mL/hr?
Answer:
Total Volume (mL)Time (hr)=1,000 mL8 hr=125 mL/hr\frac{\text{Total Volume
(mL)}}{\text{Time (hr)}} = \frac{1,000 \, \text{mL}}{8 \, \text{hr}} = 125 \, \
text{mL/hr}Time (hr)Total Volume (mL)=8hr1,000mL=125mL/hr
Question 3: Pediatric Dosage
Order: Administer amoxicillin 90 mg/kg/day in 2 divided doses.
The child weighs 15 kg. How much medication will you administer per dose?
Answer:
1. Calculate the total daily dose:
90 mg/kg/day×15 kg=1,350 mg/day90 \, \text{mg/kg/day} \times 15 \, \
text{kg} = 1,350 \, \text{mg/day}90mg/kg/day×15kg=1,350mg/day
2. Divide the total daily dose by 2:
1,350 mg2=675 mg/dose\frac{1,350 \, \text{mg}}{2} = 675 \,
\text{mg/dose}21,350mg=675mg/dose
Question 4: Weight-Based IV Medication
Order: Administer dopamine at 5 mcg/kg/min.
Patient's weight: 70 kg.
Dopamine is available as 400 mg in 250 mL of D5W.
What is the IV flow rate in mL/hr?
Answer:
, 1. Calculate the dose in mcg/min:
5 mcg/kg/min×70 kg=350 mcg/min5 \, \text{mcg/kg/min} \times 70 \, \
text{kg} = 350 \, \text{mcg/min}5mcg/kg/min×70kg=350mcg/min
2. Convert mcg to mg:
350 mcg1,000=0.35 mg/min\frac{350 \, \text{mcg}}{1,000} = 0.35 \, \
text{mg/min}1,000350mcg=0.35mg/min
3. Find the concentration of dopamine in the IV bag:
400 mg250 mL=1.6 mg/mL\frac{400 \, \text{mg}}{250 \, \text{mL}} = 1.6 \, \
text{mg/mL}250mL400mg=1.6mg/mL
4. Calculate flow rate in mL/min:
0.35 mg/min1.6 mg/mL=0.21875 mL/min\frac{0.35 \, \text{mg/min}}{1.6 \, \
text{mg/mL}} = 0.21875 \, \text{mL/min}1.6mg/mL0.35mg/min
=0.21875mL/min
5. Convert to mL/hr:
0.21875 mL/min×60 min/hr=13.125 mL/hr0.21875 \, \text{mL/min} \times 60
\, \text{min/hr} = 13.125 \,
\text{mL/hr}0.21875mL/min×60min/hr=13.125mL/hr
Rounded: 13.1 mL/hr
Question 5: Reconstitution of Powdered Medication
Order: Administer 500 mg of ceftriaxone IM.
Available: Vial labeled 1 g with instructions to reconstitute with 3.6 mL of diluent to
yield a concentration of 250 mg/mL.
How many mL will you administer?
Answer:
1. Determine the volume per mg:
250 mg1 mL=250 mg/mL\frac{\text{250 mg}}{\text{1 mL}} = 250 \, \
text{mg/mL}1 mL250 mg=250mg/mL
, 2. Calculate the volume needed for 500 mg:
500 mg250 mg/mL=2 mL\frac{500 \, \text{mg}}{250 \, \text{mg/mL}} = 2 \, \
text{mL}250mg/mL500mg=2mL
Question 6: Insulin Administration
Order: Administer 12 units of regular insulin and 20 units of NPH insulin
subcutaneously.
How many total units of insulin will you draw into the syringe?
Answer:
12 units (regular) + 20 units (NPH) = 32 units total
Question 7: Drop Factor (gtt/min)
Order: Infuse 1,000 mL over 12 hours using tubing with a drop factor of 15 gtt/mL.
What is the drip rate in gtt/min?
Answer:
1. Calculate flow rate in mL/min:
1,000 mL12 hr×60 min/hr=1.39 mL/min\frac{1,000 \, \text{mL}}{12 \, \
text{hr} \times 60 \, \text{min/hr}} = 1.39 \,
\text{mL/min}12hr×60min/hr1,000mL=1.39mL/min
2. Multiply by drop factor:
1.39 mL/min×15 gtt/mL=20.8 gtt/min1.39 \, \text{mL/min} \times 15 \, \
text{gtt/mL} = 20.8 \, \text{gtt/min}1.39mL/min×15gtt/mL=20.8gtt/min
Rounded: 21 gtt/min
Question 8: Dilution of IV Medication
Order: Administer 250 mg of vancomycin IV over 2 hours.
Available: Vial labeled 500 mg of vancomycin, to be reconstituted with 10 mL of
