NU141- Chapter 5 Dosage Calculations
Apothecary system -
a very old system of measure that was specifically developed for use by apothecaries
or pharmacists; it uses the minim as the basic unit of liquid measure and the grain as the basic
unit of solid measure
Clark rule -
a method of determining the correct drug dose for a child based on the known adult
dose (assumes that the adult dose is based on a 150-lb person); it states
Coversion -
finding the equivalent values between two systems of measure
Fried rule -
a method of determining a pediatric drug dose for a child younger than 2 years of
age, based on the child's age and the usual adult dose (assumes that an adult dose would be
appropriate for a 12.5-year-old child); it states
Metric system -
the most widely used system of measure, based on the decimal system; all units in
the system are determined as multiples of 10
Ratio and proportion -
an equation in which a ratio containing two known equivalent amounts is on one side
and a ratio containing the amount desired to convert and its unknown equivalent is on the
other side
Young rule -
a method for determining pediatric drug dose based on the child's age and the usual
adult dose; it states
A dose of 0.125 mg of digoxin was ordered for a patient who has been having trouble
swallowing. The bottle of digoxin elixir reads 0.05 mg/mL. How much would you give?
a. 5 mL
b. 0.5 mL
c. 2.5 mL
d. 2 mL -
c. 2.5 mL
The usual adult dose of diphenhydramine (Benadryl) is 50 mg. What would be the safe dose
for a child weighing 27 lb?
a. 0.9 mg
b. 1.8 mg
c. 9 mg
d. 18 mg -
c. 9mg
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, An order is written for 700 mg of ampicillin PO. The drug is supplied in liquid form as 1
g/3.5 mL. How much of the liquid should be given?
a. 5.25 mL
b. 2.55 mL
c. 6.25 mL
d. 2.45 mL -
d. 2.45 mL
An order is written for 1,000 mL of normal saline to be administered IV over 10 hours. The
drop factor on the IV tubing states 15 drops/mL. What is the IV flow rate?
a. 50 mL/h at 50 drops/min
b. 100 mL/h at 25 drops/min
c. 100 mL/h at 100 drops/min
d. 100 mL/h at 15 drops/min -
b. 100 mL/h at 25 drops/min
The average adult dose of meperidine is 75 mg. What dose would be appropriate for a 10-
month-old infant?
a. 50 mg
b. 5 mg
c. 25 mg
d. 0.5 mg -
b. 5 mg
A patient needs to take 0.75 g of tetracycline PO. The drug comes in 250-mg tablets. How
many tablets should the patient take?
a. 2 tablets
b. 3 tablets
c. 4 tablets
d. 30 tablets -
b. 3 tablets
Aminophylline is supplied in a 500 mg/2.5 mL solution. How much would be given if an
order were written for 100 mg of aminophylline IV?
a. 5 mL
b. 1.5 mL
c. 2.5 mL
d. 0.5 mL -
d. 0.5 mL
Heparin 800 units is ordered for a patient. The heparin is supplied in a multidose vial that is
labeled 10,000 units/mL. How many milliliters of heparin would be needed to treat this
patient?
a. 0.8 mL
b. 0.08 mL
c. 8 mL
d. 0.4 mL -
b. 0.08 mL
Change to equivalents within the system:
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Apothecary system -
a very old system of measure that was specifically developed for use by apothecaries
or pharmacists; it uses the minim as the basic unit of liquid measure and the grain as the basic
unit of solid measure
Clark rule -
a method of determining the correct drug dose for a child based on the known adult
dose (assumes that the adult dose is based on a 150-lb person); it states
Coversion -
finding the equivalent values between two systems of measure
Fried rule -
a method of determining a pediatric drug dose for a child younger than 2 years of
age, based on the child's age and the usual adult dose (assumes that an adult dose would be
appropriate for a 12.5-year-old child); it states
Metric system -
the most widely used system of measure, based on the decimal system; all units in
the system are determined as multiples of 10
Ratio and proportion -
an equation in which a ratio containing two known equivalent amounts is on one side
and a ratio containing the amount desired to convert and its unknown equivalent is on the
other side
Young rule -
a method for determining pediatric drug dose based on the child's age and the usual
adult dose; it states
A dose of 0.125 mg of digoxin was ordered for a patient who has been having trouble
swallowing. The bottle of digoxin elixir reads 0.05 mg/mL. How much would you give?
a. 5 mL
b. 0.5 mL
c. 2.5 mL
d. 2 mL -
c. 2.5 mL
The usual adult dose of diphenhydramine (Benadryl) is 50 mg. What would be the safe dose
for a child weighing 27 lb?
a. 0.9 mg
b. 1.8 mg
c. 9 mg
d. 18 mg -
c. 9mg
1|Page
, An order is written for 700 mg of ampicillin PO. The drug is supplied in liquid form as 1
g/3.5 mL. How much of the liquid should be given?
a. 5.25 mL
b. 2.55 mL
c. 6.25 mL
d. 2.45 mL -
d. 2.45 mL
An order is written for 1,000 mL of normal saline to be administered IV over 10 hours. The
drop factor on the IV tubing states 15 drops/mL. What is the IV flow rate?
a. 50 mL/h at 50 drops/min
b. 100 mL/h at 25 drops/min
c. 100 mL/h at 100 drops/min
d. 100 mL/h at 15 drops/min -
b. 100 mL/h at 25 drops/min
The average adult dose of meperidine is 75 mg. What dose would be appropriate for a 10-
month-old infant?
a. 50 mg
b. 5 mg
c. 25 mg
d. 0.5 mg -
b. 5 mg
A patient needs to take 0.75 g of tetracycline PO. The drug comes in 250-mg tablets. How
many tablets should the patient take?
a. 2 tablets
b. 3 tablets
c. 4 tablets
d. 30 tablets -
b. 3 tablets
Aminophylline is supplied in a 500 mg/2.5 mL solution. How much would be given if an
order were written for 100 mg of aminophylline IV?
a. 5 mL
b. 1.5 mL
c. 2.5 mL
d. 0.5 mL -
d. 0.5 mL
Heparin 800 units is ordered for a patient. The heparin is supplied in a multidose vial that is
labeled 10,000 units/mL. How many milliliters of heparin would be needed to treat this
patient?
a. 0.8 mL
b. 0.08 mL
c. 8 mL
d. 0.4 mL -
b. 0.08 mL
Change to equivalents within the system:
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