DOSAGE CALCULATION RN FUNDAMENTALS
ASSESSMENT 3.0
1. A nurse is preparing to administer codeine 20 mg PO every 6 hr PRN pain.
Available is codeine oral solution 10 mg/ 5 mL. How many mL should the
nurse administer per dose?
(Round to the nearest whole number. Use a leading zero if it applies. Do not
use a trailing zero.): Answer: 10 mL
Follow these steps for the Ratio and Proportion method of calculation:
Step 1: What is the unit of measurement the nurse should calculate? mL
Step 2: What is the dose the nurse should administer? Dose to administer =
Desired 20 mg
Step 3: What is the dose available? Dose available = Have 10 mg
Step 4: Should the nurse convert the units of measurement?
No Step 5: What is the quantity of the dose available? 5 mL
Step 6: Set up an equation and solve for X.
Have/Quantity = Desired/X
10 mg/ 5 mL = 20 mg/ X mL
X mL = 10 mL
Step 7: Round if necessary.
Step 8: Determine whether the amount to administer makes sense. If there are 10
mg/5 mL and the prescription reads 20 mg, it makes sense to administer 10 mL.
The nurse should administer codeine oral solution 10 mL PO every 6 hr PRN pain.
2. A nurse is preparing to administer eszopiclone 2,000 mcg PO to a client.
How many mg should the nurse administer?
(Round to the nearest whole number. Use a leading zero if it applies. Do not
use a trailing zero.): Answer: 2 mg
Follow these steps for the Ratio and Proportion method of calculation:
Step 1: What is the unit of measurement the nurse should calculate? mg
Step 2: What is the dose the nurse should administer? Dose to administer =
,Desired 2,000 mcg
Step 3: What is the dose available? Dose available = Have 1 mg
Step 4: Should the nurse convert the units of measurement? Yes (mcg does not
equal mg)
1,000 mcg/1 mg = 2,000 mcg/X mg
, X mg = 2 mg
Step 5: Round if necessary.
Step 6: Determine whether the amount to administer makes sense. If the
prescription reads 2,000 mcg and 1,000 mcg equals 1 mg, it makes sense to
administer 2 mg.
The nurse should administer eszopiclone 2 mg PO.
3. A nurse is preparing to administer tobramycin 4 mg/kg/day IM divided in
three equal doses to a patient who weighs 60 kg. Available is tobramycin 40
mg/mL. How many mL should the nurse administer per dose?
(Round to the nearest whole number. Use a leading zero if it applies. Do not
use a trailing zero.): Answer: 2 mL
Follow these steps for the Ratio and Proportion method of calculation:
Step 1: What is the unit of measurement the nurse should calculate? mg
Step 2: Set up an equation and solve for X.
X = Dose per kg × Client's weight in kg
X mg = 4 mg/kg × 60 kg
X mg = 240 mg
The dose is divided into three equal doses; therefore, divide X by 3.
240 mg = 80 mg3
Step 3: What is the unit of measurement the nurse should calculate? mL
Step 4: What is the dose the nurse should administer? Dose to administer =
Desired 80 mg
Step 5: What is the dose available? Dose available = Have 40 mg
Step 6: Should the nurse convert the units of measurement?
No Step 7: What is the quantity of the dose available? 1 mL
Step 8: Set up an equation and solve for X.
Have/Quantity = Desired/X
40 mg/1 mL = 80 mg/X mL
X mL = 2 mL
Step 9: Round if necessary.
Step 10: Determine whether the amount to administer makes sense. If there are
40 mg/mL and the prescription reads 4 mg/kg/day divided in three equal doses, it
ASSESSMENT 3.0
1. A nurse is preparing to administer codeine 20 mg PO every 6 hr PRN pain.
Available is codeine oral solution 10 mg/ 5 mL. How many mL should the
nurse administer per dose?
(Round to the nearest whole number. Use a leading zero if it applies. Do not
use a trailing zero.): Answer: 10 mL
Follow these steps for the Ratio and Proportion method of calculation:
Step 1: What is the unit of measurement the nurse should calculate? mL
Step 2: What is the dose the nurse should administer? Dose to administer =
Desired 20 mg
Step 3: What is the dose available? Dose available = Have 10 mg
Step 4: Should the nurse convert the units of measurement?
No Step 5: What is the quantity of the dose available? 5 mL
Step 6: Set up an equation and solve for X.
Have/Quantity = Desired/X
10 mg/ 5 mL = 20 mg/ X mL
X mL = 10 mL
Step 7: Round if necessary.
Step 8: Determine whether the amount to administer makes sense. If there are 10
mg/5 mL and the prescription reads 20 mg, it makes sense to administer 10 mL.
The nurse should administer codeine oral solution 10 mL PO every 6 hr PRN pain.
2. A nurse is preparing to administer eszopiclone 2,000 mcg PO to a client.
How many mg should the nurse administer?
(Round to the nearest whole number. Use a leading zero if it applies. Do not
use a trailing zero.): Answer: 2 mg
Follow these steps for the Ratio and Proportion method of calculation:
Step 1: What is the unit of measurement the nurse should calculate? mg
Step 2: What is the dose the nurse should administer? Dose to administer =
,Desired 2,000 mcg
Step 3: What is the dose available? Dose available = Have 1 mg
Step 4: Should the nurse convert the units of measurement? Yes (mcg does not
equal mg)
1,000 mcg/1 mg = 2,000 mcg/X mg
, X mg = 2 mg
Step 5: Round if necessary.
Step 6: Determine whether the amount to administer makes sense. If the
prescription reads 2,000 mcg and 1,000 mcg equals 1 mg, it makes sense to
administer 2 mg.
The nurse should administer eszopiclone 2 mg PO.
3. A nurse is preparing to administer tobramycin 4 mg/kg/day IM divided in
three equal doses to a patient who weighs 60 kg. Available is tobramycin 40
mg/mL. How many mL should the nurse administer per dose?
(Round to the nearest whole number. Use a leading zero if it applies. Do not
use a trailing zero.): Answer: 2 mL
Follow these steps for the Ratio and Proportion method of calculation:
Step 1: What is the unit of measurement the nurse should calculate? mg
Step 2: Set up an equation and solve for X.
X = Dose per kg × Client's weight in kg
X mg = 4 mg/kg × 60 kg
X mg = 240 mg
The dose is divided into three equal doses; therefore, divide X by 3.
240 mg = 80 mg3
Step 3: What is the unit of measurement the nurse should calculate? mL
Step 4: What is the dose the nurse should administer? Dose to administer =
Desired 80 mg
Step 5: What is the dose available? Dose available = Have 40 mg
Step 6: Should the nurse convert the units of measurement?
No Step 7: What is the quantity of the dose available? 1 mL
Step 8: Set up an equation and solve for X.
Have/Quantity = Desired/X
40 mg/1 mL = 80 mg/X mL
X mL = 2 mL
Step 9: Round if necessary.
Step 10: Determine whether the amount to administer makes sense. If there are
40 mg/mL and the prescription reads 4 mg/kg/day divided in three equal doses, it
