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Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 1
South Texas College
Associate Degree in Nursing
RNSG 1362
Clinical 1
Math and Dosage Calculations Module
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 2
Table of Contents Page
I. Basic Math
A. Fractions 3
B. Decimals 4
II. Common Calculations 6
III. Common Medical Abbreviations
A. Frequency & Route of Drug Administration 7
B. Units of Measure, and General Abbreviations 8
IV. Systems of Measurement
A. Metric System 9
B. Household System 10
C. Apothecary System 11
D. Other Common Drug Measurements 12
V. Time 13
VI. Temperature 15
VII. Drug Dosage Calculations
A. Oral Dosage of Drugs 17
B. Parenteral Dosage of Drugs 19
C. Dosages Based on Body Weight 20
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 3
Module 1: Basic Math_______________________________________________
A. Fractions
A fraction indicates a portion of a whole number.
Example: 1
4 = 1 part of 4 parts, or
1
4 of the whole
Mixed Numbers:
When a whole number and a fraction are combined, the result is referred to as a
mixed number.
Example: 15
8 = 1 +
5
8
Reducing Fractions to the Lowest Terms:
When calculating dosages, it is usually easier to work with fractions using the smallest
possible numbers.
To reduce a fraction to lowest terms, divide both the numerator and denominator by the
largest non-zero whole number that will go evenly into both numerator and denominator.
Example:
Reduce 6
12 to lowest terms
6
12 =
6 ÷ 6
12 ÷ 6 =
1
2
Note:
For tablets if the value is less than a whole number always write it in fraction.
Example:
Correct: 1 ½ tablets
Wrong: 1.5 tablets
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 4
B. Decimals
Decimal numbers are numeric values that include a whole number, a decimal point, and a
decimal fraction.
No trailing zero
When writing decimals, eliminate unnecessary zeros at the end of the number to avoid
confusion. The Joint Commission forbids the use of trailing zeros for medication orders or
other medication-related documentation and cautions that, in such cases, the decimal point
maybe missed when unnecessary zero is written.
Example: Correct: 10
Wrong: 10.0 which can be misinterpreted as 100 if decimal point is not clear.
Always place a leading zero
Always write a zero to the left of the decimal point to emphasize that the number has a value
less than 1. The Joint Commission’s Official “Do Not Use” list prohibits writing a decimal
fraction that is less than 1 without a leading zero.
Example: Correct: 0.45
Wrong: .45 which can be misinterpreted as 45 if the decimal point is not clear
or if the decimal point is overlooked.
Whole
Numbers
Decimal
Fractions
1 2 3 4 . 5 6 7 8
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Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 5
Rounding Decimal Numbers
Sometimes it is convenient to round an answer – that is, to use an approximate answer rather
than the exact one.
Rounding Off
To round off 1.267 to the 1st decimal place or 1st decimal number – do the following:
Look at the digit after the 1st decimal place (the number on the right or the number on the
2nd decimal place). Because this digit (6) is 5 or more, round off 1.267 by adding 1 to the
number on the 1st decimal place. Finally, drop all the digits after the 1st decimal place.
So, 1.267 is approximated by 1.3 when rounded off to the 1st decimal place/number.
To round off 0.8345 to the 2nd decimal place or 1st decimal number – do the following:
Look at the digit after the 2nd decimal place (the number to the right or the number on the
3rd decimal place). Because this digit (4) is less than 5, round off 0.8345 by leaving the
2nd decimal digit alone. Finally, drop all the digits after the 2nd decimal place.
So, 0.8345 is approximated by 0.83 when rounded off to the 2nd decimal place/number.
Practice Exercises:
1. Round off 3.547 to the 1st decimal place or 1st decimal number.
______________
2. Round off 3.547 to the 2 nd decimal place or 2 nd decimal number.
______________
3. Round off 3.547 to a whole number.
______________
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 6
Module II: Common Calculations______________________________________
Dosage: Formula Method
Step 1. Convert
Step 2. Think
Step 3. Calculate: Desired dose
Dose on hand x Quantity = unknown
Dosage: Ratio-Proportion Method
Step 1. Convert
Step 2. Think
Step 3. Calculate: Dosage on hand
Amount on hand =
Dosage desired
X Amount desired
Dosage: *Dimensional Analysis Method *highly recommended method to use
Step 1. Determine unit of measure for amount to give ratio for left side of equation
Step 2. Think
Step 3. Match unit of numerator of supply dosage ratio with the unit of numerator of
amount to give ratio. Set up all other ratios so units cancel, leaving unit of amount
to give. Calculate:
Amount Supply Conversion Ordered
to Give = Dosage x Factor x Dosage
Ratio Ratio Ratio Ratio
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 7
Module III: Common Medical Abbreviations____________________________
A.1. Frequency of Drug Administration
ac = before meals
ad lib = as desired, freely
hs = at bedtime, at hour of sleep
tid = three times a day
qid = four times a day
qh = every hour
q2h = every 2 hours
q3h = every 3 hours
q4h = every 4 hours
pc = after meals
prn = whenever needed, when necessary
stat = immediately, at once
A.2. Route of Drug Administration
HHN = Hand-held nebulizer
ID = Intradermal
IM = Intramuscular
IV = Intravenous
IVF = Intravenous Fluid
IVPB = Intravenous Piggyback
NGT = nasogastric tube
PEG = percutaneous endoscopic gastrostomy
po/PO = by mouth
pr/PR = per rectum
SL = Sublingual
Subcu = subcutaneous
Supp = suppository
Top = topical
od = right eye
os = left eye
ou = both eyes
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 8
B.1. Units of Measure
c = cup
cm = centimeters
ft = foot
g = grams
gr = grains
in = inches
kg = kilograms
L = liters
lb = pound
m = meters
mcg = micrograms
mEq = milliequivalents
mg = milligrams
mL = milliliters
mm = millimeters
oz = ounce
pt = pint
T /tbs = tablespoons
t/tsp = teaspoons
B.2. General
cap = capsule
ER = extended release
gtt = drop
NKA = no known allergy
NPO = nothing by mouth
SR = sustained release
susp = suspension
tab = tablet
XL/XR= extended release
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 9
Module IV: Systems of Measurement___________________________________
A. Metric System
Unit Abbreviation Equivalents
Weight gram (base unit)
milligram
microgram
kilogram
g
mg
mcg
kg
1 g = 1000 mg = 1000000 mcg
0.001 g = 1 mg = 1000 mcg
0.000001 g = 0.001 mg = 1 mcg
1 kg = 1000 g
Volume liter (base unit)
milliliter
L
mL
1 L = 1000 mL
0.001 L = 1 mL
Length
meter (base unit)
centimeter
millimeter
m
cm
mm
1 m = 100 cm = 1000 mm
0.01 m = 1 cm = 10 mm
0.001 m = 0.1 cm = 1 mm
Note: No commas on amounts at or above one thousand.
Example: Correct: 1000
Wrong: 1,000 which the comma can be misinterpreted as a decimal point if
not written legibly
Practice Exercises:
1. Change to the designated equivalents.
76 mg = ____________________ mcg
2. Change to the designated equivalents.
1.5L = ____________________ mL
3. Change to the designated equivalents.
3.36 cm = ____________________ mm
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 10
B. Household System
The household unit is likely used by patient at home where hospital measuring devices
are not usually available. You should be familiar with the household system of
measurement so that you can explain take-home prescriptions to your patient.
Equivalents
Household Measures
Metric Measures
1 t
5 mL
3 t
1 T 15 mL
2 T
1 fl oz 30 mL
1 cup
8 fl oz 240 mL
1 pint
2 cups or 16 fl oz 480 mL
1 lb
16 oz
2.2 lb
1 kg
1 in 2.54 cm
1 ft 12 in
Practice Exercises:
______ mL 1. The urinary output of a patient with an indwelling Foley catheter is 1.4 L.
How many milliliters of urine are in the bag?
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 11
______ mL 2. What is the patient’s total fluid intake in mL for the day if he had the following
fluid intake?
Breakfast = 8 oz. milk, 1 cup water
Lunch = 4 oz. juice, 3 T medication, ½ cup water
Dinner = 6 oz. soup, 12 oz soda, ½ cup water
______ oz. 3. The patient drank 720 mL of the laxative agent Colyte. How many ounces of
laxative did the patient drank?
___________________________________________________________________________
Example:
A patient needs to drink 1.5 oz. of an elixir per day. How many teaspoons would be
equivalent to this dose?
1.5 oz x 30 mL
1 oz x
1 tsp
5 mL =
45oz mL tsp
5 oz mL = 9 tsp
Practice Exercises:
______ tsp/s. 1. A patient is to take 5 mL of a medication. However, he will be using a teaspoon at
home. The nurse instructed the patient that dose will be equivalent to ____ tsp/s.
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 12
______ T 2. Order: Amoxil (amoxicillin) oral suspension 1tsp PO q8h. How many tablespoons
of Amoxil (amoxicillin) will the patient receive in 3 full days?
_______tsp 3. The order is indomethacin 75 mg PO daily in 3 divided doses. The label reads
indomethacin 25 mg per 5 mL. How many teaspoons should you administer
per dose?
Practice Exercises 4 and 5 refers to this scenario.
Scenario: A patient is given a prescription to take 15 mL of medication every 8 hours for 10
days. The patient will be using a household measuring device at home to measure
the dose of medication.
_____ tsp/s 4. How many teaspoon/s of medication will the patient take in one day?
_____ bottles 5. If the medication is supplied in a 0.5 L bottle, how many bottles will the patient
need to complete the 10 days of treatment?
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 13
Example:
Adam is 6 feet 3 inches tall. What is his height in centimeters?
6 ft x 12 in
ft = 72 in + 3 in = 75 in x
2.54 cm
in = 190.5 cm
______________________________________________________________________________
Practice Exercises:
_______ mm 1. A tumor has a diameter of 2 inches. What is the diameter of the tumor
measured in millimeters?
________ cm 2. A patient is 5 feet 9 inches tall. Find the height of the patient in centimeters.
(Round off your answer to the first decimal number/place.)
________in 3. A patient is 182 centimeters tall. Find the height of the patient in inches. (Round
off your answer to the second decimal number/place.)
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 14
Example:
Jennifer weighs 115 pounds 8 ounces. What is her weight in kilograms?
8 oz x 1 lb
16 oz =
8
16 lb = ½ lb = 0.5 lb
115 lb + 0.5 lb = 115.5 lb
115.5 lb x 1 kg
2.2 lbs =
115
2.2 kg = 52.5 kg
Practice Exercises:
_______ lb 1. A woman weighs 75 kilograms. What is her weight in pounds?
________ kg 2. Harold weighs 250 pounds now. If Harold goes on a diet and loses 30 pounds,
then how many kilograms will he weigh?
________ kg 3. An infant weighs 3400 grams. How much does this infant weigh in kilograms?
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 15
C. Apothecary System
The style of apothecary notations includes:
1. The unit or abbreviation typically precedes the amount. Example: gr v
2. Lowercase Roman numerals are often used to express whole numbers.
3. Fractions are used to designate amounts less than 1. Example: gr 1
2 , gr
1
4
4. Symbol ss used to designate the fraction 1
2 but, because this symbol can
easily be misinterpreted thus, it is no longer used.
Arabic Number Roman Numeral Apothecary Notation
1
l i or l
2
ll ii or ll
4
lV iv
5
V v
9
lX ix
10
X x
15
VX vx
20
XX xx
Equivalents:
gr i = 60 mg or 65 mg
Example # 1:
Convert: 120 mg to gr
Approximate equivalent: gr i = 60 mg. Conversion factor is 60 mg/gr
THINK: Smaller ↑ Larger → Divide
120 mg ÷ 60 mg/gr = gr 2 (Wrong)
gr ii (Correct)
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 16
Example # 2:
Order: phenobarbital gr ii PO q 8h.
On hand: phenobarbital 60 mg per tablet.
What is the amount to administer? (Use gr i = 60 mg)
gr ii x 60 mg
gr x
1 tab
60 mg =
2 x 60
60 = 2 tabs
_____________________________________________________________________________________
Practice Exercises:
______ gr 1. Convert 2400 mg to grains. (Use gr i = 60 mg)
_____mg 2. An order is for gr iii of medication. How many milligrams should the patient
receive? (Use gr i = 65 mg)
______ mL 3. Calculate the amount you will prepare for one dose.
Order: atropine gr 1/100 IM on call to O.R
Supply: atropine 0.4 mg/mL (Use gr i = 60mg)
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 17
______ mL 4. Order: morphine sulfate gr ¼ IM stat
Supply: morphine sulfate 10 mg/mL
How many milliliters of morphine would you administer? (Use gr i = 60 mg)
_________ 5. The physician ordered acetaminophen gr x po q6h prn for mild to moderate pain.
______tab/s
Stock available:
A. acetaminophen 325 mg tab.
B. acetaminophen 500 mg tab.
Which tablet are you going to use A or B & how many tab/s are you going to
administer? (Write your two (2) answers in the spaces provided.)
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 18
D. Other Common Drug Measurements
Four other measurements maybe used to indicate quantity of medicine prescribed:
international unit, unit, milliunit, and milliequivalent.
It is not necessary to learn conversions for these units of measure because medications
prescribed in these measurements are also prepared and administered in the same system.
Insulin and Epogen are measured in units
Potassium Chloride is measured in milliequivalent / mEq
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 19
Module V: Time____________________________________________________
Traditional Time International Time/ Military Time/
24h Clock Time
12:00 midnight or 12:00 AM
2400
1:00 AM
0100
6:00 AM
0600
11:00 AM
1100
12:00 noon or 12:00 PM
1200
1:00 PM
1300
6:00 PM
1800
11:00 PM
2300
Rules:
1. Traditional time and international time are the same hours starting with 1:00 AM or 0100
through 12:59 PM or 2359.
2. Minutes after 12:00 AM and before 1:00 AM are 0001 through 0059 in international
time.
3. Hours starting with 1:00 PM through 12:00 AM are 12:00 hours greater in international
time.
4. International time is designated by a unique four-digit number without a colon.
Example # 1:
1. 5:00 PM = 5:00 + 12:00 = 1700
2. 12:35 AM= 1235 – 1200 = 0035
3. 2000 = 2000 – 1200 = 8:00 PM
4. 0005 = 0005 + 1200 = 12:05 AM
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 20
Example # 2:
The patient receives an initial dose of medicine at 12:00 PM while in the physician's
office. The physician orders the medication to be taken every 6 hours. The patient should
be told to take the next dose at __________ (Use military time/24h clock time.)
1200 or 12:00 PM initial dose/1 st dose
+ 6 hrs for the next dose
1800
Practice Exercises:
_______1. Convert 1139 to conventional time.
Practice Exercises 2 and 3, refers to this scenario.
Scenario: A patient was prescribed metronidazole 500 mg PO q8h. The initial dose was
taken at 8:00 AM.
_______ 2. At what time will the patient take the next dose? (Use conventional time)
_______ 3. At what time will the patient take the 3rddose? (Use military time/24h clock time)
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 21
Module VI: Temperature_____________________________________________
The Fahrenheit scale establishes the freezing point of pure water at 32 degrees
and the boiling point of pure water at 212 degrees.
The Celsius scale establishes the freezing point of pure water at 0 degrees
and the boiling point of pure water at 100 degrees.
Conversion: Fahrenheit to Celsius, first subtract 32 and then divide the result by 1.8
ºC = ℉ − 32
1.8
Example:
Convert 98.6oF to degrees Celsius.
ºC = 98.6− 32
1.8
ºC = 66.6
1.8 = 37
Therefore, 98.6 ºF = 37 ºC
Practice Exercises:
_______ C 1. Convert 99.5o F to degrees Celsius.
______ C 2. Convert 97.2o F to degrees Celsius. (Round off to the second decimal
number/place.)
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 22
______ C 3. A mother brought her 6 yr old boy to the physician’s office due to fever, with
current temperature of 100.2 F which is equivalent to ____ C. (Round off to the
first decimal number/place.)
Practice Exercises 4 and 5, refers to this scenario.
Scenario: The state health department requires that certain medications be stored between 36 º F
and 41 º F. The refrigerator in the medication room has a Celsius thermometer.
______ ºC 4. What should be the minimum temperature setting for the refrigerator in Celsius?
(Round off to the second decimal place/number.)
______ ºC 5. What should be the maximum temperature setting for the refrigerator in Celsius?
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 23
Conversion: Celsius to Fahrenheit, first multiply by 1.8 and then add 32
ºF = ºC x 1.8 + 32
Example:
Convert 37 ºC to ºF
ºF = 1.8(37) + 32
ºF = 66.6 + 32
ºF = 98.6
Therefore, 37 ºC = 98.6 ºF
Practice Exercises:
______º F 1. Convert 38.6 ºC to degrees Fahrenheit. (Round off to the first decimal
number/place.)
______º F 2. Convert 40 ºC to degrees Fahrenheit.
______º F 3. Convert 39.3 ºC to degrees Fahrenheit. (Round off to the first decimal
number/place.)
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 24
Module Vll: Drug Dosage Calculations_________________________________
1. Oral Dosages
Example: The physician ordered 0.5 g of Zithromax four times daily for 3 days.
What is the amount to administer? Refer to label for dosage on hand.
Computation:
0.5 g
200 mg x
1000 mg
1 g x 5 mL = 12.5 mL
____________________________________________________________________________________
Practice Exercises:
_______ cap/s 1. The order is Tikosyn (dofetilide) 0.5 mg PO bid.
Stock on hand is Tikosyn (dofetilide) 125 mcg/cap.
Calculate how many capsule/s of this medication should be given to the patient.
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 25
_______tab/s 2. Order: Increase patient's current dose of Celexa 10 mg PO daily to 20 mg per day
starting next dose. See label below for dosage on hand. The new amount to administer
is ____________.
________________________________________________________________________________________________________
________ tab/s 3. The physician orders acyclovir 400 mg PO three times a day for herpes. The
medication is supplied in 800 mg tablets. How many tablets will the nurse
administer?
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 26
Practice Exercises 4 through 6 , refers to this label.
_______ mL 4. Ordered: EES Granules 400 mg PO q6h.
See label above for dose on hand.
The amount to administer per dose is ________.
_______ mg 5. How many milligrams does the whole bottle contain? (Read: Directions for
mixing or reconstituting the medicine.)
______ days 6. Based on the above computation, how many days will the whole bottle last?
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 27
_____ mL 7. Order: Nilstat Oral Suspension 250,000 units PO q.i.d.
Supply: Nilstat Oral Suspension 100,000 units per mL
How many milliliters of the medication would be given to the patient per day?
_______ g 8. The order reads Glucotrol (glipizide) 15 mg PO daily ac breakfast. How many
grams of this medication would you administer?
______ tab/s 9. The physician orders potassium chloride crystals CR 40 mEq twice a day orally
for a patient with hypokalemia. Potassium chloride crystals CR are available in
20 mEq tablets. How many tablets would the nurse administer with each dose?
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 28
_______ mg 10. Ordered amoxicillin/clavulanate 875 mg every 12 hours.
See label for medication on hand.
What is the amount to administer?
(Base dose on amount of amoxicillin available.)
(Round to the first decimal number.)
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 29
2. Parenteral Dosages
Example: Order: Humalog 15 units subcutaneous injection BID. Refer to label for drug on hand.
How many mL of Humalog will the patient receive?
Computation:
15 units x 1mL
100 units = 0.15 mL
____________________________________________________________________________________
Practice Exercises:
_____ mL 1. Order: Humalog 5 units subcutaneous injection every morning. (Refer to label below
for dose on hand.) How many milliliters of insulin will the patient receive?
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 30
Practice Exercises 2 and 3 refer to this scenario.
Scenario: The patient has the following order:
> Humulin N 20 units subcutaneous injection every morning.
> Regular Insulin subcutaneous injection ac & hs per sliding scale.
Blood Glucose Reading Insulin Dose per Sliding Scale
151 – 200 mg/dl = 2 units
201 – 250 mg/dl = 4 units
251 – 300 mg/dl = 6 units
301 – 350 mg/dl = 8 units
Greater than 350mg/dl = call MD
Stock on Hand: Humulin N 100 units per mL
Regular Insulin 100 units per mL
______ mL 2. The patient’s blood glucose before breakfast is 250 mg/dl. How many milliliters
of insulin will the patient receive?
______ units 3. What is the total amount of insulin the patient will receive this morning?
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 31
_______mL 4. Calculate the amount to administer per day.
Order: Heparin 2500 units subcutaneous injection bid
Supply: Heparin 20000 units per mL
_______ mL5. Calculate the amount to administer. Choose the correctly marked syringe.
_______ syringe
Ordered: Lanoxin 0.125 mg deep IM stat.
On hand: Lanoxin 0.25 mg/mL.
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 32
______ mL 6. Order: tobramycin sulfate 90 mg IM q8h
Supply: Nebcin (tobramycin sulfate) 80 mg per 2 mL
How many milliliters are you going to administer? (Round off your answer
to the first decimal number/place.)
______ mL 7. The physician orders Imferon 90 mg IM (Z track) for anemia. The medication is
supplied in 50 mg/mL. How many milliliters will the nurse administer?
(Round to the 1st decimal number if the dose is greater than 1 mL.)
______ mL 8.The physician orders Methergine 0.3 mg IM for postpartum bleeding.
The medication is supplied in 0.2 mg/mL.
How many milliliters will the nurse administer?
Shade the syringe.
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 33
______ mL 9. The physician orders furosemide 60 mg IV push stat for edema. How many
milliliters will the nurse administer?
(Round to the 1st decimal number if the answer is greater than 1 mL.)
______10. A patient with renal failure has orders for Epogen 5000 units subcutaneous every
Monday, Wednesday, and Friday; hold if hemoglobin is greater than 11 g/dL. The
Epogen is supplied in 10000 units per 1 milliliter vials. How many milliliters would
the nurse administer?
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 34
C. Dosages Based on Body Weight
Rule:
1. Convert the weight from pounds to kilograms (rounded to the 1st decimal number).
2. Calculate the dosage in milligram per kilogram. Multiply mg by weight in kg.
3. Compare the ordered dosage to the recommended dosage, and decide if the dosage is safe.
Example: The physician orders palifermin (Kepivance) 60 mcg/kg body weight to be
administered daily. The client weighs 88 lb. The medication is supplied 5 mg/ml.
How many milliliters would you administer per dose?
Computation:
88 lb ÷ 2.2 = 40 kg
60 mcg
kg x
1 mg
1000 mcg x 40 kg x
1 mL
5 mg =
60 x 1 x 40 x 1
1000 x 5 mL =
2400
5000 mL = 0.48 mL
_____________________________________________________________________________________
Practice Exercises:
______ mL 1. The physician orders oxacillin sodium 200 mg/kg body weight per day. The
client weighs 66 pounds. The medication is supplied 500 mg/ml. How many
milliliters would you administer?
Math and Dosage Calculations Module Level 1_rev.5/4/15 Page 35
Practice Exercises 2 through 5, refers to this scenario.
_______ mg 2. What is the recommended minimum single dosage for this child? (Round off
to the second decimal number/place.)
______ mL 3. How many milliliters of the minimum single dose will you give this child?
_______ mg 4. What is the recommended maximum single dosage for this child? (Round off
to the first decimal number.)
_______ mL 5. How many milliliters of the maximum dose will you give this child
per day?
Scenario: Order: furosemide oral solution 10 mg po b.i.d. for a child who weighs 16 lbs.
The recommended pediatric dosage is 0.5 – 2 mg/kg to be given in two divided doses.
The label reads: furosemide 10 mg/mL oral solution.