20
DOSAGE CALCULATION RULES & CONVERSIONS
Students must adhere to the following rules:
• Show all calculations.
• Apply the accepted equivalents of measure provided in the table.
• Place a “0” preceding all decimal doses (0.5). No trailing zeros (5.0 - - this is incorrect).
• IV problems expressed as drops per minute will be rounded to the whole number. (Example: 12.4 gtts / min is
expressed 12 gtts / min & 12.8 gtts / min is expressed 13 gtts / min). (Not applicable to Pediatrics)
• Dosage Problems on the Exam will state to carry to the 1st or 2nd decimal place and to round to the 1st or 2nd decimal
place. No rounding until the final answer.
• Answers may be expressed as decimals or fractions.
In administering medications in the clinical setting the student learns to “think like a nurse” based on:
• The mathematical answer to the problem.
• The medication to be administered.
• The equipment to be used.
These variables may change in different clinical settings. (Example: 1.8 tablets, the nurse administers 2 tablets).
ACCEPTED MEASUREMENTS AND CONVERSIONS
METRIC Abbreviations:
liter - L
Milliliter – mL
gram – g
milligram – mg
microgram – mcg
kilogram – kg
ounce – oz
drops - gtts
Equivalencies:
1 L = 1000 mL
1 g = 1000 mg
1 mg = 1000 mcg
1 kg = 1000 g
1 kg = 2.2 lbs
1 lb = 16 oz
1 oz = 30 mL
5 mL = 1 tsp
15 mL = 1 Tbsp.
1 inch = 2.54 cm
micro gtts=60gtts
/
mL
METRIC Volume:
Liter
Milliliter
Weight:
gram
milligram
microgram
kilogram
Length:
centimeter
NUMBERS ROMAN
I
V
X
ARABIC
1
5
10
APOTHECARY Volume:
Ounce
Weight:
P
ound
Revised 11 / 2016
