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Pharmacology for Nurses

C | Drug Conversion Tables

Pharmacology for NursesC | Drug Conversion Tables

Drug conversion tables are utilized with dosage calculations to ensure an appropriate dosage of a drug is being administered to the client as ordered. The metric system is used for prescribing medications, but at times nurses may need to explain medication dosages to clients using household measurements.

Table C1 shows common metric and U.S. customary units of measurement used in health Table C2 shows household equivalents. Drug Administration and the Nursing Process discusses conversion in more detail.

Weight 1 kilogram (kg)
 1 gram (g)
 1 milligram (mg)		 1000 grams (g)
 1000 milligrams (mg)
 1000 micrograms (mcg or µg)		 2.2 pounds (lb or #)
 0.035274 ounces (oz)
Volume 1 liter (L) 1000 milliliters (mL) 4.22675 cups
Length 1 kilometer (km)
 1 meter (m)
 1 centimeter (cm)
 2.54 centimeters (cm)		 1000 meters (m)
 100 centimeters (cm)
 10 millimeters (mm)
 25.4 millimeters (mm)		 3281 feet (ft)
 3.281 feet (ft)
 0.393 inches (in.)
 1 inch (in.)
Table C1 Common Metric and U.S. Customary Units of Measurement (sources: https://www.math-salamanders.com/metric-to-standard-conversion-chart.html; https://www.unitconverters.net/volume/liters-to-cups.htm; https://www.nist.gov/pml/owm/approximate-conversions-metric-us-customary-measures; https://www.nist.gov/pml/owm/approximate-conversions-us-customary-measures-metric)
Volume 1 cup 8 fluid ounces (fl oz) 236.6 milliliters (mL)
1 fluid ounce (fl oz) 29.57 milliliters (mL)
1 tablespoon (Tbsp) 3 teaspoons (tsp) 14.79 milliliters (mL)
1 teaspoon (tsp) 4.93 milliliters (mL)
Table C2 Household Equivalents (sources: https://www.math-salamanders.com/metric-to-standard-conversion-chart.html; https://www.unitconverters.net/volume/liters-to-cups.htm; https://www.nist.gov/pml/owm/approximate-conversions-metric-us-customary-measures; https://www.nist.gov/pml/owm/approximate-conversions-us-customary-measures-metric)
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