1. The Pharmacy Technician 4E Chapter 6 Basic Pharmaceutical Measurement Calculation

2. Comparison of Roman and Arabic Numerals

7. Common Metric Units: Weight Basic Unit Equivalent 1 gram (g) 1000 milligrams (mg) 1 milligram (mg) 1000 micrograms (mcg) 1 kilogram (kg) 1000 grams (g)

17. Remember When setting up a proportion to solve a conversion, the units in the numerators must match, and the units in the denominators must match.

18. Example 3 Solve for X

21. Equivalent Values

23. Converting a Ratio to a Percent 5:1 = 5/1 × 100% = 5 × 100% = 500% 1:5 = 1/5 × 100% = 100%/5 = 20% 1:2 = 1/2 × 100% = 100%/2 = 50%

25. Converting a Percent to a Ratio 2% = 2 ÷ 100 = 2/100 = 1/50 = 1:50 10% = 10 ÷ 100 = 10/100 = 1/10 = 1:10 75% = 75 ÷ 100 = 75/100 = 3/4 = 3:4

28. Percent to Decimal 4% = 0.04 4 ÷ 100% = 0.04 15% = 0.15 15 ÷ 100% = 0.15 200% = 2 200 ÷ 100% = 2 Decimal to Percent 0.25 = 25% 0.25 × 100% = 25% 1.35 = 135% 1.35 × 100% = 135% 0.015 = 1.5% 0.015 × 100% = 1.5%

29. Example 4 How many milliliters are there in 1 gal, 12 fl oz? According to the values in Table 5.7, 3840 mL are found in 1 gal. Because 1 fl oz contains 30 mL, you can use the ratio-proportion method to calculate the amount of milliliters in 12 fl oz as follows:

30. Example 4 How many milliliters are there in 1 gal, 12 fl oz?

31. Example A solution is to be used to fill hypodermic syringes, each containing 60 mL, and 3 L of the solution is available. How many hypodermic syringes can be filled with the 3 L of solution? 1 L is 1000 mL. The available supply of solution is therefore Determine the number of syringes by using the ratio-proportion method:

32. Example How many hypodermic syringes can be filled with the 3 L of solution?

33. Example You are to dispense 300 mL of a liquid preparation. If the dose is 2 tsp, how many doses will there be in the final preparation? Begin solving this problem by converting to a common unit of measure using conversion values.

34. Example 6 If the dose is 2 tsp, how many doses will there be in the final preparation? Using these converted measurements, the solution can be determined one of two ways: Solution 1: Using the ratio proportion method and the metric system.

35. Example 6 If the dose is 2 tsp, how many doses will there be in the final preparation?

36. Example 7 How many grains of acetaminophen should be used in a Rx for 400 mg acetaminophen? Solve this problem by using the ratio-proportion method. The unknown number of grains and the requested number of milligrams go on the left side, and the ratio of 1 gr 65 mg goes on the right side, per Table 5.5.

37. Example 7 How many grains of acetaminophen should be used in the prescription?

38. Example 8 A physician wants a patient to be given 0.8 mg of nitroglycerin. On hand are tablets containing nitroglycerin 1/150 gr. How many tablets should the patient be given? Begin solving this problem by determining the number of grains in a dose by setting up a proportion and solving for the unknown.

39. Example 8 How many tablets should the patient be given?

41. Example 9 You have a stock solution that contains 10 mg of active ingredient per 5 mL of solution. The physician orders a dose of 4 mg. How many milliliters of the stock solution will have to be administered?

42. Example 9 How many milliliters of the stock solution will have to be administered?

43. Example 10 An order calls for Demerol 75 mg IM q4h prn pain. The supply available is in Demerol 100 mg/mL syringes. How many milliliters will the nurse give for one injection?

44. Example 10 How many milliliters will the nurse give for one injection?

46. Example 11 What is the proper pediatric dose?

47. Example 11 What is the proper pediatric dose?

49. Example 12 Using the formula for solving for powder volume, determine the diluent volume.

50. Example 12 Using the formula for solving for powder volume, determine the diluent volume.

52. Example 13 What is the powder volume? Step 1. Calculate the final volume. The strength of the final solution will be 100 mg/mL .

53. Example 13 What is the powder volume?

55. Example 14 How much diluent will you need if the original product is in a 1 mL vial and you dilute the entire vial?

56. Example 14 How much diluent will you need if the original product is in a 1 mL vial and you dilute the entire vial?

58. Example 15 How many milliliters of each will be needed? Step 1. Set up a box arrangement and at the upper-left corner, write the percent of the highest concentration (50%) as a whole number.

59. Example 15 How many milliliters of each will be needed? Step 2. Subtract the center number from the upper-left number (i.e., the smaller from the larger) and put it at the lower-right corner. Now subtract the lower-left number from the center number (i.e., the smaller from the larger), and put it at the upper-right corner.

60. Example 15 How many milliliters of each will be needed? 7.5 2.5 mL parts D50W 42.5 mL parts D5W 45 mL total parts D7.5W 50 5

61. Example 15 How many milliliters of each will be needed?

62. Example 15 How many milliliters of each will be needed?

63. Example 15 How many milliliters of each will be needed ?

64. Example 15 How many milliliters of each will be needed?

65. Example 15 How many milliliters of each will be needed?