Practice Math Calculations
1. You need to administer a 3 mg dose of a medication, on hand is 4 mg/ml. How much do you need to
draw up?
2. 375 mg of a liquid medication is ordered. You have available 125mg per 5ml, how much do you pour?
3. 25 mg of a medication is ordered IV; the vial is labeled 5 mg/2 ml. How many mls will you give?
4. An order reads for 0.1 mg of a medication to be given pre-op; available solution is 0.4 mg/2 ml. How
much will you give?
5. The physician orders 1.25 mg of a medication daily for your patient. The only available tablet strength
is 0.625 mg. What amount will you give?
6. Motrin 0.6g is ordered; available tablets contain 600 mg. How many tablets will you give?
7. 0.5 mg of a medication is ordered; available tablets contain 0.25 mg per tablet. How many tablets will
you give?
8. Convert 7.5 grams to milligrams.
Converting Pounds to Kilograms
1.
2.
3.
4.
5.
6.
7.
30 lb = _____________
15 lb 5 oz = _________
7 ¼ lb = ____________
22 lb = _____________
4 lb 5 oz = __________
75 lb = _____________
10 ½ lbs = __________
Pediatric Dosage Calculations
Problem 1
Child weighs 33 lbs
Physician order: Augmentin 150 mg po q 8 hours
Information from drug guide: children < 40 kg receive 6.7 to 13.3 mg/kg q 8 hours
Convert 33 lbs to kg ________
Calculate low and high dose _______ low dose _______ high dose
Is the dose in the safe range? ___________
The medication comes Augmentin 125 mg / 5 mL
How many mL would you need to draw up to equal 150 mg? _________
Problem 2
Child weighs 16 lb 10 oz
Physician order: Lasix 15 mg po bid
Information from drug guide:
The initial dose of Lasix (furosemide) for infants or children is 2 mg / kg / dose.
If initial dose works dosage may be increased to 1 or 2 mg / kg / dose (maintenance dose).
Doses greater than 6 mg / kg / day are not recommended.
Convert 16 lb 10 oz to kg ________
Calculate initial and high dose _______ initial dose _______ high dose
Is the dose in the safe range? ___________
The medication comes: Furosemide 10 mg/mL
How many mL would you need to draw up to equal 15 mg? _________
Answer Sheet:
1. 0.75 cc
2. 15 ml
3. 10 ml
4. 0. 5ml
5. 2 tabs
6. 1 tab
7. 2 tabs
8. 7500 mg
Converting
1. 13.63 kg 2. 15.31 lb = 6.95 kg 3. 7.25 lb = 3.29 kg 4. 10 kg
5. 4.31 lb = 1.95 kg 6. 34.09 kg 7. 4.77kg
Answer problem 1:
15 kg
Low dose 100.5 mg (6.7 x 15 kg)
High dose 199.5 mg (13.3 x 15 kg)
Safe range (100.5 mg to 199.5 mg) 150 mg is a safe dose.
You would give 6 mL
Calculation
125 mg = 150 mg = 750 or
5 mL
x mL
125 x
Answer Problem 2
16.62 pounds to 7.556 kg or 7.56 kg
Single dose of Lasix 7.56 kg x 2 mg = 15.12 mg/dose
High range daily dose 7.56 kg x 6 mg = 45.36 mg/dose
Is the dosage of 15 mg bid or 30 mg / day safe? = yes
How many mL? 1.5 mL
15
Calculation: 10 mg = 15 mg or 10 X 1=1.5ml
1 mL
x mL
150
125
X 5 =6ml