Lab 1 Pharmacy Compounding

aa.

of each

ad. lib.

as needed or when needed

a.m.

morning

Aq Purif.

purified water

b.i.d.

twice a day

caps.

capsules

disp.

dispense

div.

divide

d.t.d.

dispense such doses

et

and

g

gram

gal

gallon

gr.

grain

gtt.

drop

h.

hour

h.s.

at bedtime

kg

kilogram

lb

avoirdupois pound

lb (with line through top)

apothecary pound

Lot.

lotion

M. ft.

mix and make

M

minim

mEq

milliequivalents

mg

milligram

mL

milliliter

MW

molecular weight

M.W.Q.

minimum weight quantity

N.F.

National Formulary

oz

avoirdupois ounce

p.c.

after meals

p.r.n. or prn

as needed

pt

pint

q.

every

q.d.

every day

q.s.

a sufficient quantity

q.s. ad

quantity sufficient added to make

qt

quart

S.A. or s.a.

secundum artem (according to the art of pharmacy)

si opus sit.

when necessary, when needed

Sig.

write on label

sp. gr.

specific gravity

SR

sensitivity requirement

susp.

suspension

tab. trit.

tablet triturates

tbsp.

tablespoon (15 mL)

t.i.d.

three times a day

tsp.

teaspoon (5 mL)

U.S.P.

United States Pharmacopeia

U, u

Write out unit...

IU

Write out International Unit

Q.D., QD, q.d.

Write daily

Q.O.D., QOD, q.o.d.

Write every other day

Trailing Zero (Ex: 2.0 mg)

Write with no trailing zeros (Ex: 2 mg)

Lack of leading zero (Ex: .2 mg)

Write with a leading zero (Ex: 0.2 mg)

MS, MSO4, MgSO4

Write out Morphine Sulfate or Magnesium Sulfate

What is another name for a Prescription Balance?

Class A or Class III Balance

What is the maximum allowable weight permitted on a Prescription Balance?

120 g

What is the sensitivity requirement for a Prescription Balance?

6 mg

What is an initial quality control procedure a pharmacist should complete before using a prescription balance for compounding?

Balance the balance or level the balance

What is the maximum allowable weighing error customarily allowed in pharmacy compounding?

+/- 5%

If a balance has a sensitivity of 4 mg, what is the balance's minimum weighable quantity?

4 mg x 20 = 80 mg

Why would a pharmacist triturate insoluble powders when compounding?

To process and mix ingredients and/or to increase surface area by reducing particle size.

Why and how was geometric dilution used to prepare the dusting powder?

It allowed a homogeneous mixture to be prepared by placing the powder with the smallest volume in the mortar first and triturating it with an equal amount of another powder until uniform and then continuing the process by doubling the amount of powder added to the mortar each time with trituration until all the powders were mixed and homogeneous.

What therapeutic property did Calamine have in the dusting powder?

Protectant, slightly astringent, slightly antiseptic

What therapeutic property did Zinc Oxide have in the dusting powder?

Protectant, slight astringent, slightly antiseptic

What therapeutic property did Red Mercuric Oxide have in the dusting powder?

Topical antiseptic

What therapeutic property did Heavy Magnesium Oxide have in the dusting powder?

Soothing vehicle

What type of condition could the dusting powder be used to treat?

Weeping skin condition such as eczema

When should a pharmacist use a glassine weighing paper rather than a powder weighing paper on a balance?

When weighing a sticky, greasy, or thick component such as an ointment or thick liquid.

If you have 3 g of Calamine powder in a total of 75 g of dusting powder, what percentage of Calamine is in the dusting powder?

3 g/ 75 g x 100% = 4% w/w

If the sensitivity of a balance is 5 mg, what is the percentage of error in weighing if 135 mg is weighed on the balance?

5 mg/ 135 mg x 100% = 3.7%

If the sensitivity of a balance is 5 mg, what is the percentage of error in weighing if 13.5 g is weighed on the balance?

5 mg/ 13,500 mg x 100% = 0.037%

If the sensitivity of a balance is 5 mg, can 85 mg be weighed on the balance without incurring greater than a 5% weighing error?

NO, 85 mg cannot be weighed on the balance because it is not sufficiently sensitive. The MWQ for a balance with a sensitivity of 5 mg is 100 mg.

Basic Test for the Balance

Sensitivity Requirement

Arm Ratio Test

Shift Test

Rider and Graduated Dial Test

Sensitivity Requirement

Defined as the load that will cause a change of one division on the index plate of the balance.

Determined by leveling the balance, determine the rest point of the balance, and determine the smallest weight that causes the rest point to shift one division on the index plate.

Number of divisions shifted by weight/ weight = 1 division/ X mg

Weighing Error or Percentage of Error

%Error = Sensitivity/Quantity Weighted (mg) x 100%

Minimum Weighable Quantity

Value that will not exceed a variance of +/- 5%

MWQ = Sensitivity x 20

Avoirdupois System

Used in the United States in measuring body weight and in selling goods by the ounce or pound, is slowly giving way to the metric system.

Apothecaries' System

Once the predominant pharmacist's system of volumetric and weight measurements.

1 gram =

15.432 grain

1 grain =

64.8 mg

1 lb (avoir) =

454 gram

1 oz (avoir) =

28.35 gram

1 oz (apoth) =

31.1 gram

1 kg =

2.2 lb (avoir)

1 lb (apoth) =

373 gram

1 mL =

16.23 minims

1 fluidrachm (dram) =

60 minims

1 fl. oz. =

29.57 mL

1 tsp. =

5 mL

1 tbsp. =

15 mL

1 wineglassful =

60 mL

1 teacupful =

120 mL

1 tumblerful =

240 mL

1 pt. =

473 mL

1 qt =

946 mL

1 gallon (US) =

3785 mL

1 gallon (US) =

128 fl. oz.

1 mL =

20 drops of water with each drop weighing 50 mg

Trituration

Process by which we use the mortar and pestle to:

process and mix components

decrease particle size and increase surface area

triturate and scrape