Добавил:
kiopkiopkiop18@yandex.ru t.me/Prokururor I Вовсе не секретарь, но почту проверяю Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз: Предмет: Файл:

Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_5576_Библиотеки_им_академика_М_И_Перельмана

.pdf
Скачиваний:
0
Добавлен:
30.08.2026
Размер:
45 Мб
Скачать
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
Practice Problems
550.66 gallons
31.45% w/w 4% w/v 66 g polyethylene glycol ointment base
0.87 g progesterone gel (8% w/w)
985.67 mL 3 g hydrocortisone cream (1% w/w) 27 g cream base 1000 mL water 1:315.42 w/v 1250 mL boric acid solution
6694.44 mL water 2 mL undecylenic acid 6 bottles 12 mL stock solution
18.75 mL of the 2.0-molar solution 0 mL diluent 248 mL boric acid solution 50 mL infusion
0.76 molar
1.25% w/w
0.01 mL concentrate
0.061% w/w a. 14.42 g chlorhexidine gluconate
b. 180.24 mg/mL
28.24 mL stock solution
0.42% hypericin 20 mL lotion base
1.46 mL lactic acid solution 45 g bexarotene gel
15 g gel base
226.804 mg mupirocin powder 45 mL memantine oral solution
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
49.
50.
51.
52.
53.
54.
55.
56.
57.
15 mL sorbitol solution a. 3.101% w/w
b. 1.98% w/w
4.15 mL liquefied phenol
0.002% w/v 1:20,000 w/v 250 mL suspension base 180 g white petrolatum 3632 g benzocaine ointment, 2.5%
4.79 g salicylic acid 30 g ointment base 1 g hydrocortisone acetate ointment, 2.5%
9 g ophthalmic base 1:633.33 w/v
1.67 g zinc oxide
0.07% w/w
0.011% w/v
0.08 mL antigen, 0.2% 100 mg sodium fluoride a. 24 mL corn oil
6 mL cyclosporine solution b. 10 mL corn oil
0.09 mL gentamicin solution and 5.91 mL diluent
9.17% w/v
1.26% w/w hydrocortisone 1% w/w pramoxine
2450 mg diluent 3:5 (5%:1%) 3:17 (20% ointment:petrolatum) a. 2.5 mg/mL ibuprofen
b. 0.25% w/v ibuprofen 60 mL chlorpromazine hydrochloride injection
440 mL sodium chloride injection 100 mL lidocaine hydrochloride injection 495 mL sodium chloride injection
Данная книга находится в списке для перевода на русский язык сайта https://meduniver.com/
58.
59.
60.
1.
2.
3.
4.
5.
0.16 mL amikacin injection and 9.84 mL normal saline solution
2.33 mL sterile water for injection 500 mg colchicine dilution
References
Karolchyk S. Treating patients allergic to poison ivy. International Journal of Pharmaceutical Compounding 1998;2:421.
Prince SJ. Calculations. International Journal of Pharmaceutical Compounding 1998;2:310. Prince SJ. Calculations. International Journal of Pharmaceutical Compounding 1998;2:453. Prince SJ. Calculations. International Journal of Pharmaceutical Compounding 2000;4:393. Prince SJ. Calculations. International Journal of Pharmaceutical Compounding 1999;3:145.
16
Reducing and Enlarging
Formulas
OBJECTIVE
Upon successful completion of this chapter, the student will be able to:
Perform calculations by various methods to reduce or enlarge
formulas for pharmaceutical preparations.
Introduction
Pharmacists may have to reduce or enlarge formulas for pharmaceutical preparations in the course of their professional practice or manufacturing activities. Formulas in the United States Pharmacopeia–National Formulary generally are based on the preparation of 1000 mL or 1000 g of product. Formulas from other sources may be based on other quantities.
The need to prepare different quantities of a pharmaceutical product depends on the nature of the practice. Whereas only small quantities may be required in a community pharmacy, modest quantities in a hospital pharmacy, and larger quantities in outsourcing facilities, very large quantities are prepared in the pharmaceutical manufacturing industry. In the latter case, hundreds of thousands of dosage units may be prepared in a single production batch.
The important criterion is that irrespective of the quantity prepared, the correct proportion of one ingredient to the other in a given formula must be maintained.
Methods to Reduce or Enlarge Formulas
As demonstrated in this section, the methods of ratio and proportion, dimensional analysis, and the factor method may be used to reduce or
Данная книга находится в списке для перевода на русский язык сайта https://meduniver.com/
enlarge a pharmaceutical formula. For many, the factor method is the simplest to use. When using the factor method, it is important to note that the factor should be carried out to several decimal places or not rounded, to avoid rounding errors.
Example calculations
1. From the following standard formula for Calamine Topical
Suspension USP,1 calculate the quantity of each ingredient required to prepare 240 mL of product.
Solving by Ratio and Proportion
Solving by Dimensional Analysis
and so forth for each ingredient, arriving at the same answers as shown in the preceding section.
Solving by the Factor Method
The factor method is based on the relative quantity of the total formula to be prepared. For instance, in the problem example, 240 mL of a
1000-mL standard formula are to be prepared. The factor is derived as follows:
Then, by multiplying the quantity of each ingredient in the standard formula by the factor, the correct quantity of that ingredient is determined. Thus, 80 g × 0.24 = 19.2 g calamine, and so forth for each ingredient, arriving at the same answers as shown earlier.
1. From the following formula for artificial tears,2 calculate the
quantity of each ingredient required to prepare a dozen 30-mL containers.
30 mL/container × 12 containers = 360 mL
Using the factor 3.6, the quantity of each ingredient is calculated:
1. From the following formula for an estradiol vaginal gel,3 calculate the quantity of each ingredient required to prepare 1 lb of gel.
Данная книга находится в списке для перевода на русский язык сайта https://meduniver.com/
Using the factor 1.534, the quantity of each ingredient is calculated:
1. From the following formula for a dexamethasone ophthalmic
ointment,4 calculate the quantity of each ingredient needed to prepare 7.5 g of ointment.
Using the factor 0.075, the quantity of each ingredient is calculated:
Formulas That Specify Proportional Parts
On a rare occasion, a pharmacist may encounter an old formula that indicates the ingredients in “parts” rather than in measures of weight or volume. The parts indicate the relative proportion of each of the
ingredients in the formula. A formula for solid or semisolid ingredients may be considered in terms of grams, whereas a formula of liquids may be considered in terms of milliliters.
Example calculation of a formula expressed in parts
From the following formula, calculate the quantity of each ingredient required to make 1000 g of the ointment.
and
and
Данная книга находится в списке для перевода на русский язык сайта https://meduniver.com/
1.
2.
3.
4.
An alternative method at solution would be to determine that there are
15.385 g per part (1000 g/65 parts) and thus
PRACTICE PROBLEMS
From the following formula for 40 sertraline hydrochloride capsules,5 calculate the quantity of each ingredient needed to
prepare 250 such capsules.
From the following formula for a progesterone nasal spray,
6
calculate the quantity of each ingredient needed to prepare twenty-four 15-mL containers of the spray.
From the following formula, calculate the quantities required to make 5 lb of hydrophilic ointment.
The formula, by weight, for a tube of an ophthalmic ointment is as follows:
5.
6.
7.
8.
How much of each ingredient would be needed to manufacture 2000 such tubes of ointment?
Calculate the quantity of each ingredient needed to prepare 15 mL of the following ophthalmic solution.
7
According to the literature, the biotechnology product pegfilgrastim (NEULASTA) contains the following in 0.6 mL
pre-filled syringes8:
How much of the first three ingredients would be needed to manufacture 100,000 such syringes?
From the following formula, calculate the quantity of each ingredient required to make 1500 g of the powder.
The following is a formula for 100 triple estrogen capsules.
9
Calculate the quantities of the first three ingredients, in grams, and the last two ingredients, in kilograms, required to prepare 5000 such capsules.
Данная книга находится в списке для перевода на русский язык сайта https://meduniver.com/