Bishop State Community College
Dosage Calculation Review Study Booklet
Table of Contents
Page Numbers
Conversion Table ………………………………. 2
Conversions Facts………………………………. 3, 4
Conversion Practice Problems………………… 5
Oral and Parenteral Calculations…………….. 6, 7
Oral and Parenteral practice problems………. 8
Reconstitution of Drug…………………………. 9
Reconstitution practice problems……………… 9
Pediatric drug calculations…………………….. 10
Rounding children dosages and weight……….. 11
Pediatric Practice problems…………………… 12
Intravenous fluid administration……………… 14,15,16,17
Calculating IV infusion Time ………………… 18
Calculating IV Fluid Volume …………………. 19
Practice Problems (IV Time and Volume)…….. 19, 20
Practice IV Problems…………………………… 21, 22
Critical Care IV Calculations………………….. 23
IV Medication Ordered/min…………………… 24
IV Medication Ordered/Kg/Min………………. 25
Advance Dosages Practice Problems…………. 26, 27
Practice Problems Answers…………………… 28, 29, 30
The Official “Do Not Use List”………………. 31
References……………………………………… 32
1
, Conversion Table to be Memorized
Conversion Table
Metric Volume Weights: Apothecary/
Household to Metric
1 L= 1000 mL 1 gr = 60 mg
15 gr = 1 g
Metric Weight 2.2 lbs = 1 kg
1000 mcg = 1 mg Solutions
1000 mg = 1 g 1 g per 100 mL = 1% solution
1000 g = 1 kg 25 g per 100 mL = 25 % solution
Length 100 g per 100 mL = 100% solution
1 inch = 2.5 centimeters
Liquids
1 mL = 1cc 15 mL = 3 tsp 2 c = 1 pt
1 mL = 15 gtts 15 mL = 1 Tbs 1000 mL = 1 qt
1 mL = 15 minims 30 mL = 1 oz 32 oz = 1 qt
1 mL = 60 microdrops 1 Tbs = 3 tsp 1 L = 1 qt
4 mL = 1 dram 8 dram = 1 oz 1 L = 1000 mL
5 mL = 1 tsp 240 mL = 1 c 4 qt = 1 gal
500 mL = 1 pt
2
,Conversions: Metric, Apothecary, and Household System
Converting from one unit to another using the conversion factor method
Recall the equivalents
Multiply or divide
Rule to convert from a larger to a smaller unit measurement, multiply by the
conversion factor.
Think: “Larger is going down to smaller, so you will multiply.”
Larger↓ Smaller→ Multiply (X)
Example: How many cups are in 3 quart? You know that 1 quart =4 cups.
Cups are smaller than quarts. THINK:
LARGER↓SMALLER→MULTIPLY(X)
The conversion Factor is 4 cups /1 quart
Multiply by the conversion factor
Quarts (larger unit) X conversion factor (cups/qt) = cups (smaller unit)
3 qt X 4 cups/qt = 12 cups
Rule to convert from a smaller to a larger unit of measurement, divide by the conversion
factor.
THINK: “Smaller is going to larger, so you will divide.” Smaller ↑ Larger → Divide ( )
Example: How many quarts are in 8 cups?
You know that 1 qt= 4 cups. The conversion factor is 4 cups/1 quart. Quarts are larger
than cups. Divide by the conversion factor because it takes fewer of the quart unit to equal
the same amount of the cup unit. THINK: SMALLER ↑LARGER → Divide 8 cups
4 cups/qt = 2 qt
3
, Things to consider when Drug Calculation Problems require Conversions
1. Look at what is available and what you want to give. Ask yourself the
question, “Are the drugs in the same units of measure?”
2. If the drugs are not in the same units of measure, convert one.
3. It is best to convert to the metric system, since it is a decimal system and
you will not have to deal with fractions.
4. Sometimes you must convert within the same system of measure to
make like units. Example: grams to milligrams.
5. Two steps.
A. Convert the dose from the system in which it is ordered to the system in
which it is available.
B. Calculate the amount needed to obtain the desired dose.
4
Dosage Calculation Review Study Booklet
Table of Contents
Page Numbers
Conversion Table ………………………………. 2
Conversions Facts………………………………. 3, 4
Conversion Practice Problems………………… 5
Oral and Parenteral Calculations…………….. 6, 7
Oral and Parenteral practice problems………. 8
Reconstitution of Drug…………………………. 9
Reconstitution practice problems……………… 9
Pediatric drug calculations…………………….. 10
Rounding children dosages and weight……….. 11
Pediatric Practice problems…………………… 12
Intravenous fluid administration……………… 14,15,16,17
Calculating IV infusion Time ………………… 18
Calculating IV Fluid Volume …………………. 19
Practice Problems (IV Time and Volume)…….. 19, 20
Practice IV Problems…………………………… 21, 22
Critical Care IV Calculations………………….. 23
IV Medication Ordered/min…………………… 24
IV Medication Ordered/Kg/Min………………. 25
Advance Dosages Practice Problems…………. 26, 27
Practice Problems Answers…………………… 28, 29, 30
The Official “Do Not Use List”………………. 31
References……………………………………… 32
1
, Conversion Table to be Memorized
Conversion Table
Metric Volume Weights: Apothecary/
Household to Metric
1 L= 1000 mL 1 gr = 60 mg
15 gr = 1 g
Metric Weight 2.2 lbs = 1 kg
1000 mcg = 1 mg Solutions
1000 mg = 1 g 1 g per 100 mL = 1% solution
1000 g = 1 kg 25 g per 100 mL = 25 % solution
Length 100 g per 100 mL = 100% solution
1 inch = 2.5 centimeters
Liquids
1 mL = 1cc 15 mL = 3 tsp 2 c = 1 pt
1 mL = 15 gtts 15 mL = 1 Tbs 1000 mL = 1 qt
1 mL = 15 minims 30 mL = 1 oz 32 oz = 1 qt
1 mL = 60 microdrops 1 Tbs = 3 tsp 1 L = 1 qt
4 mL = 1 dram 8 dram = 1 oz 1 L = 1000 mL
5 mL = 1 tsp 240 mL = 1 c 4 qt = 1 gal
500 mL = 1 pt
2
,Conversions: Metric, Apothecary, and Household System
Converting from one unit to another using the conversion factor method
Recall the equivalents
Multiply or divide
Rule to convert from a larger to a smaller unit measurement, multiply by the
conversion factor.
Think: “Larger is going down to smaller, so you will multiply.”
Larger↓ Smaller→ Multiply (X)
Example: How many cups are in 3 quart? You know that 1 quart =4 cups.
Cups are smaller than quarts. THINK:
LARGER↓SMALLER→MULTIPLY(X)
The conversion Factor is 4 cups /1 quart
Multiply by the conversion factor
Quarts (larger unit) X conversion factor (cups/qt) = cups (smaller unit)
3 qt X 4 cups/qt = 12 cups
Rule to convert from a smaller to a larger unit of measurement, divide by the conversion
factor.
THINK: “Smaller is going to larger, so you will divide.” Smaller ↑ Larger → Divide ( )
Example: How many quarts are in 8 cups?
You know that 1 qt= 4 cups. The conversion factor is 4 cups/1 quart. Quarts are larger
than cups. Divide by the conversion factor because it takes fewer of the quart unit to equal
the same amount of the cup unit. THINK: SMALLER ↑LARGER → Divide 8 cups
4 cups/qt = 2 qt
3
, Things to consider when Drug Calculation Problems require Conversions
1. Look at what is available and what you want to give. Ask yourself the
question, “Are the drugs in the same units of measure?”
2. If the drugs are not in the same units of measure, convert one.
3. It is best to convert to the metric system, since it is a decimal system and
you will not have to deal with fractions.
4. Sometimes you must convert within the same system of measure to
make like units. Example: grams to milligrams.
5. Two steps.
A. Convert the dose from the system in which it is ordered to the system in
which it is available.
B. Calculate the amount needed to obtain the desired dose.
4
