Medical Mathematics (Speedy Study Guides). Speedy Publishing

      

      The metric system of measurement is the most widely used system of measurement in the world. It is the preferred system for administering medications, because it is based on a series of 10 measures or multiples of 10. It is a simple and accurate form of measurement between health care professionals.

      Metric Weight Measures

      1 kilogram (kg, Kg) = 1000 grams or 1000 g

      1 gram = 1000 milligrams or 1000 mg

      1 milligram (mg) = 1000 micrograms 1 microgram

      (mcg) = 0.001 milligrams or 0.001 mg

      1 milligram = 0.001 gram or 0.001 g

      1 microgram (mcg) = 0.000001 gram

      Metric Volume Measures

      1 milliliter (ml) = 0.001 liter or 0.001 L

      1 liter = 1000 milliliters or 1000 ml

      1 kiloliter = 1000 liters or 1000 L

      Metric Length Measures

      1 millimeter (mm) = 0.001 meter

      1 centimeter (cm) = 0.01 meter or 0.01 m

      1 decimeter (dm) = 0.1 meter or 0.1 m

      1 kilometer (km) = 1000 meters or 1000 m

      1 meter (m) = 100 centimeters or 100 cm

      1 meter (m) = 1000 millimeters or 1000 mm

      1 centimeter (cm) = 10 millimeters or 10 mm

      The apothecaries system of measurement is the oldest system of drug measurement. In fact, it was the first system used to measure medication amounts. It is infrequently used as a drug measurement. There are a few medications that are still measured in grains (gr). To ensure administration of the correct dose of medication to a patient, it is important to know the conversion of grains to milligrams and how to convert from one system of measurement to another.

      Apothecaries measures

      60 grains (gr) = 1 dram

      8 drams = 1 ounce or 1 oz.

      1 fluid dram = 60 minims

      The household system of measurement is based on the apothecary system of measures. Household measures are used to measure liquid medications. Parents understand one

      teaspoon of liquid medication more clearly than ordering 15 milliliters. The important thing to realize with household measures is that these measures are not as exact as the metric system of measurement. Also the comparison of metric measures to household measures are not equal. These measures are called equivalent measures because the measurement is close enough. A liter is very close in equal measurement to a quart. It is not an exact measure. It is an equivalent.

      Household measures

      3 teaspoons (tsp) = 1 tablespoon or 1 tbsp

      1 ounce (oz) = 2 tablespoons or 2 tbsp

      1 pint (pt) = 2 cups or 2 c

      1 pint (pt) = 16 ounces or 16 oz

      1 juice glass = 4 ounces or 4 oz

      1 coffee cup = Usually 6 ounces or 6 oz, but can

      vary depending on size of cup.

      1 glass = 8 ounces or 8 oz

      1 measuring cup (c) = 8 ounces or 8 oz

      1 teaspoon (tsp) = 60 drops or 60 gtt