4.3 Household Measurement System
The household measurement system is a system used in homes, particularly in kitchens, in the United States. The units of household measurement for volume are drop, teaspoon, tablespoon, cup, pint, quart, and gallon. The units of household measurement for weight are ounces and pounds. Table 4.6 lists the household measurement equivalents and their abbreviations. Figure 4.2 illustrates household measurement equivalents.
Safety Alert
To avoid misreading the abbreviation c as the abbreviation cc or as the number 0, pharmacy technicians should not abbreviate the household unit cup using a lowercase letter “c.”
Table 4.6 Household Measurement System Equivalents
Volume |
Weight |
|---|---|
3 teaspoonfuls (tsp) = 1 tablespoonful (tbsp) |
1 pound (lb) = 16 ounces (oz) |
2 tablespoonfuls (tbsp) = 1 fluid ounce (f l oz) |
|
8 fluid ounces (fl oz) = 1 cup |
|
2 cups = 1 pint (pt) |
|
2 pints (pt) = 1 quart (qt) |
|
4 quarts (qt) = 1 gallon (gal) |
In addition to measuring volumes for cooking and baking, household measurement utensils, such as teaspoons and tablespoons, have been used by patients for decades to administer liquid medications at home. Consequently, labels on these medications provide patient instructions in household measurement units.
However, using household measurement utensils to measure medication volumes can be less accurate than using standard measurement devices that have graduation marks. For that reason, there is a growing trend among prescribers and pharmacies to use the preferred metric measurement system for medication doses. To that end, pharmacies often provide dosing spoons, droppers, and dosing cups marked with both metric and household measurement units.
Dosing spoons, droppers, and dosing cups are frequently marked with both metric and household measurement units.
Figure 4.2 Household Units for Volume and Their Equivalents
4.3 Problem Set
State the abbreviation for each of the following household measurement units.
teaspoon
pound
tablespoon
fluid ounce
pint
quart
gallon
Use Table 4.6 to supply the household measurement equivalents.
3 tsp = ____________ tbsp
1 cup = ____________ fl oz
1 lb = _____________ oz
4 qt = _____________ gal
1 qt = _____________ pt
1 pt = _____________ cups
Applications
Use the scenario below to answer the following questions.
A prescription for a liquid medication states that the patient should take 1 fl oz three times daily.
What is an equivalent dose in tablespoons?
How many tablespoonfuls would a patient take in 24 hours?
Self-check your work in Appendix A.