Metric & Household Measurements BCC Pharmacy Tech

Metric Measurements  Metric system=system of choice for dealing with weights and measures in the calculations of drug dosages  Decimal system  0.5  0.75  0.007

 Certain prefixes identify multiples of 10 that are being used.  4 most common; micro, milli, centi, kilo  Prefixes can be used with any of the base units weight (gram), volume (liter) or length (meter)

 Weight  1,000,000 mcg=1 g  1,000 mcg = 1 mg  1000 mg =1 g  1000 g = 1 kg  Volume  1000 mL = 1 L  1 cc = 1mL  Length  1 m = 1,000 mm or 100 cm  1 cm = 10 mm or 0.01 m  1 mm = 0.1 cm or m

Example  300 mg equals how many grams? 100 mg: 1 g:: _____ mg: _____ g 1000 mg: 1 g :: 300 mg: __x__ g

More Practice  2.5 L equals how many milliliters?  180 mcg equals how many grams?  15 mm equals how many centimeters?

Household Measurements  Household measures are not accurate enough for the nurse to use in the calculation of drug dosages in the hospital.  Metric equivalents are used.  I & O or intake and output

Metric Household Equivalents  Metric Measure = Household Measure  5 mL = 1 tsp  15 mL = 1 Tbsp  30 mL = 1 oz  240 mL = 1 standard measuring cup  1 kg or 1000 g = 2.2 lb  2.5 cm = 1 in  1 foot = 12 inches

Example  1 ½ cups equals how many milliliters?  1 cup : 240 mL ::  1 cup : 240 mL :: _____ cups : _____mL  1 cup : 240 mL :: 1 ½ cups : __x__ mL

More Practice  35 kg equals how many pounds?  18 inches equals how many centimeters?

To do  Memorize the tables of metric and household measurements.  Study material on forming proportions for the calculations problems relating to these measurements.  Complete the worksheet  Check your answers  Evaluate your learning