LABORATORY EQUIPMENTS

No Equipment Diagram Uses

1.
Graduated common sizes are 10, 25, 50, 100, 250 and 500
measuring ml. Marked with milliliter (ml) scale and is
cylinder used to measure volume of liquid

2. Glass or plastic container, common sizes are

50, 100, 250, 500 and 1000ml
Beaker
Used as a container in preparation of products,
measurement, mixing
3.
Made of glass or plastic; used in pouring or
Funnel funneling liquids to avoid spills and used to
hold a filter paper during filtration

4. Mortar &
Made of porcelain or glass; used to grind
Pestle
products to form powder
5. Used for quick, accurate weighing of
Electronic
ingredients or reagents (solids or certain
balance
liquids)
6.
Used for determining the weight of solids or
Triple beam
liquids or reagents in grams and weight of
balance
empty container
7. Evaporating Made stainless steel used in evaporation of
dish solvent from product over a water bath
8.
Used to measure and transfer small quantities
Pipette
of liquid <5mL

9.
This is made of porcelain; used to heat small
Crucible &
amounts of solid substances over high
cover
temperatures
10. Used to transfer small amounts of liquids drop
Dropper
by drop
11. Common sizes are 125 ml, 250 ml, 500ml; has
a thin neck and a wide base; used to hold
Erlenmeyer
liquids when carrying out reaction, preparing
or conical
pharmaceutical products.
flask
Allows mixing and swirling of the flask
without spilling
26 General Pharmacy Practical Manual

No Equipment Diagram Uses

12. Suppository They are made of stainless steel; used in the
molds preparation of suppositories
13.
Employed in dry heat sterilization
Hot air oven

14.

Employed in moist heat sterilization

Autoclave

15.

Heating and melting of ingredients

Water bath

16.
Marked with a milliliter scale and fitted with a
stopcock; can be used to add a specific
volumes of solutions especially during
Burettes titrations

17. Laboratory
Made of metal; has a flat rounded end and a
spoons /
rectangular end; used to transfer solid
spatula
ingredients during measuring and in trituration
18. Pipette Used together with pipette to measure small
pumps volume liquids
19. Usually made of glass; used to stir products to
Stirring rod
make homogenous mixtures
20.
Glassware that comes in many sizes; it has
Test tube
many uses and can be heated
21. Test tube Brush with wire handle; used to scrub thin
brush glassware
22.
Test tube
Used to hold a test tube
holder

23.
Test tube Used to hold test tubes in an upright position;
rack usually made of wood or plastic
 Extemporaneous preparation 27

No Equipment Diagram Uses

24.
A metal heating device connected to a gas
Bunsen
outlet with rubber tubing; used as a source of
burner
heat to heat contents in beakers or test tubes

25.
Thermometer Used to determine temperature

26. Packaging
bottles

27. Ointment jars

28.

29.

30.

31.

32.

33.

34.

35.
28 General Pharmacy Practical Manual

MEASUREMENTS OF VOLUME, WEIGHT & LENGTH

Measuring volume
The common instruments for measuring volume are cylindrical or conical (cone-shaped)
graduated glass or plastic. For the measurement of small volumes a pipette or calibrated
syringe may be used
It is best to select a measure or containers with a capacity equal to or just exceeding the
volume to be measured as small volumes in large measure containers will increase the size of
the error
Examples include
 Measuring cylinder (glass or plastic)
 Conical flask
 Beakers (glass or plastic)
 Pipette (preferably with auto pump)
 Syringe
Note
a) When measuring; ensure accurate measure by carefully observing the meniscus at
the eye level
b) Avoid any spillages; in case they do occur clean them immediately
c) Volatile compounds should be measured when they are to incorporated in the
product or the container should be covered
d) All the items measure should be labeled
e) In case you pick from the stock container return the excess back
Weighing
Different weights, balances and scales may be used in the measurement of different
components required in extemporaneous compounding. Each instrument selected must meet
the standards for sensitivity, accuracy and capacity
Examples
 Class A prescription balances; hand operated and used in the filling of prescriptions
or in small-scale compound; they have a sensitivity requirement (SR) of 6 milligrams.
However they should not weigh less than 120 milligrams of material to avoid > 5%
error in a weighing
 Electronic weighing balances; highly sensitive
Note
 Always protect the weighing scale during weighing and remove them after weighing
 Balance the scale to zero
 Weigh the accurate amount
 Return the weights to zero maintain the sensitivity of the scale
 Avoid any spillages or in case of any spillages clean immediately
 When weighing items like soft paraffin or any semisolid, wet or spread the piece of
paper with part item to be weighed
 All the materials weighed should be labeled
 Return any excess to stock container
 Extemporaneous preparation 29

Conversion of volume to weight using specific gravity

Specific gravity is a ratio of the weight of a substance to the weight of an equal volume of a
substance chosen as a standard, both substances at the same temperature.
Water is used as the standard for the specific gravities of liquids and solids; the most useful
standard for gases is hydrogen
Specific gravity =

Application in measurements
Specific gravity is used as a factor in a calculation to convert between weight and volume
such as conversions in preparation of syrup. Sometime the volume is given yet, syrup are
supposed to be prepare in grams and easily converted if specific gravity is given
Grams = Milliliters x Specific gravity
1. What is the weight, in grams, of 500 mL of alcohol with a specific gravity of
0.820?
2. You are required to prepare 40mls of syrup BP. If syrup has specific gravity of
1.313, calculate the weight of syrup to be prepared considering an excess of 10mls
Aliquot method of weighing and measuring
An aliquot is a fraction, portion, or part that is contained in an exact number of times in
another. This used when degree of precision in measurement that is beyond the capacity of
the instrument at hand is required
This is a method by which small quantities of a substance may be obtained within the desired
degree of accuracy by weighing or measuring a larger-than-needed portion of the substance,
diluting it with an inert material, and then weighing or measuring a portion (aliquot) of the
mixture calculated to contain the desired amount of the needed substance.
Smallest quantity =

Procedure for solids

1. Select a multiple factor and multiply with quantity of active drug in the question. The
answer should be at least higher than the smallest quantity ≥ 120 mg
2. Dilute the quantity with an inert substance. Multiply the factor with the smallest amount
calculate; subtract the amount from quantity of drug to be weighed and get the actual
amount of diluent to weigh
3. Weigh the aliquot portion of the dilution that contains the desired quantity
Aliquot = x total mixture
Procedure for volume
1. Select a multiple factor and multiply with quantity in the question; the answer should be
measurable per the scale of the measuring device to be used
2. Dilute with quantity of compatible diluent (solvent) to an amount evenly divisible by
the multiple selected.
30 General Pharmacy Practical Manual: By M. Wilson and L. Brian

3. Measure the aliquot of the dilution that contains the quantity originally desired
Aliquot = x total mixture

NOTE: The answer of the aliquot may vary depending on multiple factor used

1. A balance with a sensitivity requirement of 6mg is to be used to measure 5mg of

active drug; explain how it will be measured
Smallest quantity = = 120mg
Step 1: will choose multiple factor of 25
= 25 x 5 = 125mg of active drug weighed
Step 2: diluent to be used = 25 x 120 = 3000mg
= drug + diluent =3000mg
= diluent alone = 3000mg- 125mg = 2875mg
Step 3: aliquot portion
= x 3000 mg (drug + diluent)
= 120mg of aliquot part will be weigh off
:. Weigh 125mg of drug mix with 2875mg of diluent to get uniform mixture;
weigh of 120mg of mixture and will contain 5mg of drug
Proof
x 125 of drug substance 5mg
115mg
x 2875 of diluent
Total 120mg
2. A balance with a sensitivity requirement of 7mg is to be used to measure 10mg
of active drug; explain how it will be measured using lactose as a diluent

3. A formula requires 0.5ml of acetic acid to be used using 10ml measuring

cylinder. explain how it will be measured using water as a solvent

4. A formula requires 0.4 mL of clove oil. Using a 10-mL graduate. explain how it
will be measured using alcohol as a solvent

For Least weighable quantity, refer to parenteral products

 Solutions 31

LIQUID DOSAGE FORM

Examples include
 Solutions
 Suspensions
 Emulsions

SOLUTIONS

1. Define solutions
Solutions are homogenous mixtures of one or more solute dissolved or dispersed in a
suitable solvent.
Pharmaceutical solutions are liquid preparations in which the active pharmaceutical
ingredient and other excipients are dissolved in suitable solvent forming a
homogenous mixture. Pharmaceutical solutions are used in many routes such as oral,
rectal, ophthalmic, parenteral and otic
Drugs are commonly given in solution in cough/cold remedies and in medications
for the young (pediatric)

2. List examples of pharmaceutical solutions

 Syrups: concentrated solution of sugar up to 66.7% BP
 Elixirs: hydro alcoholic solution for oral use
 Linctus‟s: employed in treatment of cough
 Mouthwashes/gargles: fi treatment of infection and inflammation of the oral
cavity and manage halitosis
 Enemas

3. List advantages and disadvantages of solution dosage forms

Advantages
 Easier to swallow; useful in pediatric patients
 Faster absorption than sold drugs
 Uniform distribution of active drug
 Unpalatable drugs can be taken through taste-masking
Disadvantages
 Bulky to transport and store by the patient
 Unsuitable for drugs chemically unstable in water
 Aqueous solvent provide media for microbial growth; require preservation
 Inaccurate dose measurement
32 General Pharmacy Practical Manual

4. List the component of solution dosage forms

 Active pharmaceutical ingredients
 Vehicle: carrier for active drug; water commonly used
 Co-solvents: increase solubility of active drug; glycerol, ethanol, propylene
glycol
 Preservatives: control microbial growth; Benzoic acid, Benzalkonium
chloride, Parabens
 Buffers: control the pH of the formulated product; acetic acid and sodium
acetate, (citric acid and sodium citrate, sodium phosphate and disodium
phosphate)
 Sweetening agents: increase the palatability of the therapeutic agent -
sucrose, liquid glucose, glycerol, saccharin and aspartame.
 Colorants:
 Flavorings agents: mint, anise, apricot, vanilla,
 Antioxidants: prevent chemical degradation by oxidation

5. Explain the packaging of solutions

Solutions are packaged plastic or glass containers. Glass bottle are sometimes amber
in case of light sensitive drugs in the product

6. You are provided with the following drug products

A. Mouth wash
B. Linctus
C. Mixture (quinine)
Identify the products
State the advantages and disadvantages of above dosage form

Extemporaneous preparation of solutions

Solutions can easily be prepared in pharmacy laboratory by simple process of mixing until
the solid ingredients are completely dissolved in the solvent
An introduction during practical‟s
1. Ensure that your working area is clean
2. Pick and wash all the equipment‟s
3. Determine the working formula in case you are provided with a master formula or
search the index of official to search the location of formula
4. While weighing
(i) Ensure the units are in grams “g”
(ii) Use class B weighing scale or digital scale when available
(iii) Always protect the weighing scale. Common mistake is when you find the scale
protected and continue; please demonstrate protecting the scale
(iv) Keep your working area clean; any spillages should be cleaned immediately
(v) Avoid picking the ingredient from the stock container. Use other small piece of
paper and always return the excess back
(vi) Always label all the paper used in weighing with name and quantity weighed
(vii) Always weigh accurately all the ingredients
 Solutions 33

5. While measuring
(i) Always use clean equipment‟s
(ii) Use measuring cylinder or pipette if volumes less than 5mls
(iii) Avoid any spillages; clean any spills to keep a clean working area
(iv) Label all the measured ingredients; label on a paper name and quantity and place
the container on top of the paper
(v) Always measure accurately all the ingredients
NOTE: Liquids can also be weighed over a weighing scale
6. While mixing
(i) Always mix or stir gently in one direction
(ii) Follow the principles in product being prepared
(iii) All the ingredients should be used
7. While packaging - use an appropriate container and polish the bottle with a clean towel
to remove any spillages on the bottle
8. Labeling
(i) The label should be neat, written properly and highly organized
(ii) Always the label should fit on the selected packaging bottle
Warning “ Do not swallow” or “shake bottle before use”
Quantity
Name and Strength (BP)
Direction of use of product
Ingredients (in 5mls) or %

Manufactured Date: Batch Number:

Expiry date: 1 month gap Name of patient:
Storage Store in cool dry place away from direct sunlight
conditions: Keep out of reach of children

Discard 2 weeks after opening

Address of manufacturer
General principles of solution preparation
1. Write out the formula either from the prescription (unofficial) or from an official text
(official).
2. Calculate the quantities required for each ingredient in the formula to produce the
required final volume. Remember to cater for transference losses which may occur in
some preparations like syrups
3. Weigh all solids and measure liquids
4. Identify the soluble solids and calculate the quantity of vehicle required to fully
dissolve the solids (using solubility from official books). If more than one solid is to
be dissolved, they are dissolved one by one, in order of solubility (i.e. the least
soluble first
5. Transfer the appropriate amount of vehicle to a glass or plastic beaker
6. If necessary, transfer the solid to a glass mortar and use the glass pestle to reduce
particle size to aid dissolution.
7. Transfer the solid to the beaker and stir to aid dissolution. If a mortar and pestle have
been used to reduce particle size, ensure that the mortar is rinsed with a little vehicle
to ensure completer transfer of the powders.
34 General Pharmacy Practical Manual

8. When all the solid have dissolved, transfer the solution to the a tarred packaging
bottle (final container)
9. Rinse out the beaker in which the solution was made with a portion of the vehicle and
transfer the rinsing‟s to the packaging bottle containing other solution
10. Add any remaining liquid ingredients (volatile liquid) to the packaging bottle and
shake to form homogenous mixture
11. Make up to final volume with remaining vehicle.
12. Polish the packaging bottle, label, polish and dispense to the patient.
NOTE:
1. Not all solutions are prepared using the same steps
2. Syrups are sticky always add an excess
3. Syrups are always prepared in grams (g) in case of volume is given, used specific
gravity to convert to grams
4. Other solution products, do not require an addition of excess

Question 1 You are provided with the following master formula for oral
dextrose solution
Anhydrous dextrose 80g
Anise water 40ml
Distilled water to 1000mL
a) Determine the working formula for preparing 60ml of oral
dextrose solution
b) Write method of preparation
c) Write a label for the product

Determine working formula

1. Quantity to be prepared = 60ml
2. Quantity of anhydrous dextrose =
3. Quantity of anise water =
4. Working formula
Anhydrous dextrose 4.8g
Anise water 2.4ml
Distilled water to 60mL
Write method of preparation
Weighing and measuring of ingredients
5. Cleans the weighing scale and working area
6. Protects the weighing scale
7. Balances the weighing scale to zero
8. Accurately weighed 4.8g of anhydrous dextrose
9. Accurately measured 2.4mls of anise water using pipette
10. Accurately measured about 30mls of distilled water using a measuring cylinder
11. No spillages on the pan of weighing scale and during measuring
12. Labels weighed and measured ingredients with name and quantity
13. Returned the weights back to zero
14. Maintains a clean environment
 Solutions 35

Procedure of preparation
15. Picked and cleaned the equipments: beaker, measuring cylinder, stirring rod,
packaging bottle
16. Inverts the equipments to drain any excess water
17. Transfers the measured distilled water to beaker
18. Add the weighed anhydrous dextrose to beaker containing distilled water
19. Stirred the mixture until dissolved
20. Tarred a packaging bottle to 60ml mark
21. Transferred the mixture into a tarred bottle
22. Rinsed the beaker with about 10mls of distilled water and added the rinsing‟s to tarred
bottle
23. Added the measured anise water to tarred bottle and agitated to ensure homogenous
product
24. Topped to mark with the remaining distilled water
25. Agitated the bottle
26. No spillages observed
27. Polished the bottle
28. Maintained a clean area
Label of the product
For internal use only
60ml
Oral dextrose solution
Use as directed
Shake the bottle before use
To be diluted with equal amount of warm water before use
Ingredients (Each 5mls contains)
Anhydrous dextrose: 0.4g
Anise water: 0.2g
Manufacture date :
Expiry date :
Batch Number :
Store in cool dry place away from direct sun light
Keep out of reach of children
Discard two weeks after opening
Name of manufacturer
Registration Number
Address Name of school - Pharmacy Lab P.O
Box, 724, Fort Portal
36 General Pharmacy Practical Manual

Question 2 You are with sodium chloride 0.9% w/v BP and mint solution 0.5% v/v
a) Determine working formula for preparing a dozen 60mL bottles of
0.9% w/v sodium chloride mouth wash solution BP containing
mint flavor
b) Write the method of preparation
c) Write a label for the product

Determine working formula

1. Extracting formula
Sodium chloride 0.9% w/v
Mint solution 0.5% v/v
Distilled water to 100%
2. Quantity to be prepared: dozen means 12;
= 12 x 60ml = 720mL
3. Quantity of sodium chloride =
4. Quantity of mint =
5. Working formula
Sodium chloride 6.5g
Mint solution 3.6mL
Distilled water to 720mL
Method of preparation
Weighing and measuring of ingredients
6. Cleans the weighing scale and working area
7. Protects the weighing scale
8. Balances the weighing scale to zero
9. Accurately weighed 6.5g of sodium chloride
10. Accurately measured 3.6mls of mint using pipette
11. Accurately measured about 100mls of distilled water using a measuring cylinder
12. No spillages on the pan of weighing scale and during measuring
13. Labels weighed and measured ingredients with name and quantity
14. Returned the weights back to zero
15. Maintains a clean environment
Procedure of preparation
16. Picked and cleaned the equipments: beaker, measuring cylinder, stirring rod,
packaging bottle
17. Inverts the equipments to drain any excess water
18. Transfers the measured distilled water to beaker
19. Add the weighed sodium chloride to beaker containing distilled water
20. Stirred the mixture until dissolved
21. Add mint solution and stirred to ensure homogenous solution
22. Transferred the mixture into a 1L measuring cylinder
23. Rinsed the beaker with about 10mls of distilled water and added the rinsing‟s to 1L
measuring cylinder
24. Topped to mark with the remaining distilled water
 Solutions 37

25. Stirred to ensure homogenous solution

26. Packed in 60ml in each of the 12 packaging bottles
27. No spillages observed
28. Polished the packaging bottles
29. Maintained a clean area
Label of the product
For oral use only
60ml
Sodium chloride 0.9% w/v mouth wash solution BP
Use as directed
Shake the bottle before use
Ingredients (Each 5mls contains)
Sodium chloride: 0.54g
Mint solution: 0.3mL
Manufacture date :
Expiry date :
Batch Number :
Store in cool dry place away from direct sun light
Keep out of reach of children
Discard two weeks after opening
Name of manufacturer
Registration Number
Address Name of school - Pharmacy Lab P.O
Box, 724, Fort Portal

Question 3 You are provided with following master formula for syrup BP
Sucrose 66.7%
Purified water to 100%
a) Determine the working formula 60g of syrup BP
b) Write the method of preparation
c) Write a label for the product to be used as sweetener

Determine the working formula

1. Syrups are sticky, will prepare an excess of 10g
2. Total weight to be prepare: 60 + 10 = 70g
3. Quantity of sucrose: 46.7g
4. Percentage of distilled water: 100 - 66.7 = 33.3%
5. Quantity of distilled water:
6. Working formula
Sucrose 46.7g
Purified water to 23.3g
38 General Pharmacy Practical Manual

Method of preparation
Weighing of ingredients
7. Cleans the weighing scale and working area
8. Protects the weighing scale
9. Balances the weighing scale to zero
10. Accurately weighs 33.3g of sucrose and 16.7g of distilled water
11. No spillages on the pan of weighing scale
12. Returns excess sucrose to the stock container
13. Labels all the ingredients weighed with name and quantity
14. Maintains a clean environment
Procedure of preparation
15. Equipment‟s to use: Evaporating dish, plastic beaker, stirring rod, measuring cylinder,
packaging bottle, weighing balance and weighing papers
16. Transferred the measured distilled water to the plastic beaker or evaporating dish to
water bath at a temperature of 80-85oC for about 2-4 minutes
17. Removed the water from water bath
18. Added the sucrose to the evaporating dish
19. Stir until all the sucrose is dissolved
20. Transferred the evaporating dish to water bath in case sucrose does not dissolve
21. Continued to stir until cold
22. Maintained a clean working environment
Packing of 60g of the syrup BP
23. Protected weighing scale
24. Balanced the weighing scale
25. Tarred the packaging bottle on weighing scale
26. Removed the water from water bath
27. Weighed off 60g accurately of syrup
28. Polished the bottle
Label of the product
40g
FOR INTERNAL USE ONLY
SYRUP BP
CONTAINS: Sucrose 66.7% W/V
Manufacture date : Date of practical
Expiry date 1 month gap
Batch number
To be used as sweetener
Discard two weeks after opening
Store in a cool dry place away from direct sunlight
Keep out of reach of children
Name of manufacturer
Registration Number
Address Name of school - Pharmacy Lab
P.O Box, 724, Fort Portal
 Solutions 39

Question 4 Develop a working formula for preparing 35ml of Syrup BP

Sucrose 66.7%
Purified water to 33.3%
Note: specific gravity of syrup 1.313g/ml

Determine the working formula

1. Converting 35ml to grams
Specific gravity =
Mass = 35 x 1.313 = 46g
2. Syrups are sticky, will prepare an excess of 10g
3. Total weight to be prepare: 46 + 10 = 56g
4. Quantity of sucrose: 37.4g
5. Quantity of distilled water:
6. Working formula
Sucrose 37.4g
Purified water to 18.6g
Note: Will weigh off 46g equivalent to 35ml of the syrup

Question 5 Prepare 80ml 0f compound sodium chloride mouthwash BP; and dispense
to Peter to use 5mls TDS for 4days
Sodium bicarbonate 10g
Sodium Chloride 15g
Concentrated peppermint emulsion 25mls
Double strength Chloroform water 500ml
Distilled water sufficient to produce 1000mls
Determining working formula
1. Calculations
Sodium bicarbonate = 10 = 0.8g
Sodium chloride = 15 = 1.2g
Peppermint emulsion = 25 = 2mls
DS Chloroform water = = 40mls
1. Working formula
Sodium bicarbonate 0.8g
Sodium chloride 1.2g
Concentrated peppermint emulsion 2mls
Double strength Chloroform water 40mls
Distilled water sufficient to produce 80mls
40 General Pharmacy Practical Manual: By M. Wilson and L. Brian

2. Solubility
Sodium bicarbonate 1 in 11 parts
1g dissolves in 11 mls of water
0.8 will dissolve = 0.8x11= 8.8mls
Sodium chloride 1 in 3 parts
1g dissolves in 3 mls of water
1.2g will dissolve =1.2 x 3 = 3.6mls
3. Initial volume to measure 8.8mls + 3.6mls = 12.4mls; however will choose 30mls and
measure DS chloroform water
Weighing and measuring of ingredients
4. Cleans the weighing scale and working area
5. Protects the weighing scale
6. Balances the weighing scale
7. Accurately weighed 0.8g of sodium bicarbonate, 1.2g of sodium chloride
8. Accurately measured 2mls of peppermint using pipette
9. Accurately measure 40mls of DS Chloroform water using a measuring cylinder
10. No spillages on the pan of weighing scale
11. Labels weighed and measured ingredients
12. Returned the weights back to zero
13. Maintains a clean environment
Procedure
14. Transfers 30mls of the measured DS chloroform water to beaker
15. Add the weighed sodium bicarbonate to beaker containing DS chloroform
16. Stirred the mixture until dissolved
17. Add the weighed sodium chloride to beaker
18. Stirred the mixture until dissolved
19. Tarred packaging bottle to 80ml
20. Transferred the mixture into a tarred bottle
21. Rinsed the beaker with about 10mls of distilled water and added the rinsing‟s to tarred
bottle
22. Added the peppermint to tarred bottle and agitated to ensure homogenous product
23. Topped to mark with the remaining DS chloroform water and water
24. Agitated the bottle
25. No spillages observed
26. Polished the bottle
27. Maintained a clean area
Label of the product
 Solutions 41

For Oral Use; Do Not Swallow

80ml
Compound Sodium Chloride Mouth wash BP
Gargle 5 mls three times a day for days;
Shake the bottle before use
To be diluted with equal amount of warm water before use
Ingredients (Each 5mls contains)
Sodium bicarbonate:
Sodium chloride:
Manufacture date :
Expiry date :
Batch Number :
Name of client : Peter
Store in cool dry place away from direct sun light
Keep out of reach of children
Discard the remaining after use
Name of manufacturer
Registration Number
Address Name of school - Pharmacy Lab P.O
Box, 724, Fort Portal

Question 6 Prepare 75mls of the gargle BPC

Potassium chlorate 30g
Patent blue V 5g
Liquefied phenol 15ml
Purified water to 1000ml
a) Develop working formula
b) Write method of preparation
c) Write a label for the product
Hint: Dissolve potassium chlorate in 150ml of warm water. Add the
liquefied phenol. Added the dye, mix to form homogenous mixture and top
to volume

Develop working formula

1. Prepare 75mls of the product
2. Potassium chlorate = 30g = 2.3g
3. Patent blue V = 5g = 0.4g
4. Liquefied phenol = 15ml = 1.1ml
5. Working formula
Potassium chlorate 2.3g
Patent blue V 0.4g
Liquefied phenol 1.1ml
Purified water to 75ml
42 General Pharmacy Practical Manual

Method of preparation
Weighing and measuring of ingredients
6. Clean the working area and weighing scale
7. Protect the weighing scale
8. Adjust the weighing scale to zero
9. Weighed 2.3g of potassium chlorate, 0.4g of patent blue V on a weighing scale
balance
10. Measured 1.1 ml of liquefied with pipette
11. Measured about 40mls of distilled water using a measuring cylinder
12. Labelled all the weighed ingredients with name and quantity
13. Maintained clean working area
14. Returned the weights of the scale back to zero
Procedure of preparation
15. Picked and cleaned the equipments: Measuring cylinder, stirring rod, beaker,
packaging bottle,
16. Transferred the measured distilled water in beaker
17. Added the potassium chlorate to the beaker
18. Stirred the mixture until completely dissolved
19. Added the liquefied phenol and stirred to form uniform mixture
20. Added dye (patent blue V) to the beaker and stirred until stirred dissolved
21. Tarred packaging bottle to 75ml
22. Transferred the mixture into a tarred bottle
23. Rinsed the beaker with about 10mls of distilled water and added the rinsing‟s to tarred
bottle
24. Topped to mark with water
25. Agitated the bottle to form uniform product
26. No spillages observed
27. Polished the bottle
28. Maintained a clean area
Write a label of the product
75ml
For Oral Use; Do Not Swallow
The gargle BPC
Use as directed by physician
To be diluted with equal amount of warm water before use
Ingredients (Each 5mls contains)
Potassium chlorate
Manufacture date : date of practical
Expiry date :
Batch Number :
Store in cool dry place away from direct sun light
Keep out of reach of children
Name of manufacturer
Registration Number
Address Name of school - Pharmacy Lab P.O
Box, 724, Fort Portal
 Solutions 43

Question 7 You are provided with the following working formula for iodine solution
Iodine 100ml
Ethanol 5% to 1000ml
a) Develop a working formula for preparing 35mL of iodine solution
b) Write method of preparation
c) Write a label for the product
Develop working formula
1. Quantity to be prepared 35ml
2. Quantity of iodine required =
3. Working formula
Iodine 3.5mL
Ethanol 5% to 35mL
Write method of preparation
4. Cleaned working area
5. Picked and cleaned equipments: measuring cylinder, stirring rod, beaker, pipette,
packaging bottle
6. Inverted the equipments to drain water
7. Accurately measured 3.5ml of iodine solution using pipette
8. Transferred the solution to 50ml measuring cylinder
9. Added ethanol 5% to measuring until 35ml mark
10. Stirred to obtain homogenous solution
11. Ensure clean working area
12. Transferred to packaging bottle
13. Polished the bottle
14. Labelled the product
35ml
For external used only
Iodine solution
Use as directed by physician
Ingredients
Iodine 10%

Manufacture date : date of practical

Expiry date :
Batch Number :
Store in cool dry place away from direct sun light
Keep out of reach of children
Discard the remaining after use
Name of manufacturer
Registration Number
Address Name of school - Pharmacy Lab P.O
Box, 724, Fort Portal
44 General Pharmacy Practical Manual

Dilution of solution
The formula used has been explained in Pharmaceutical calculations
C1V1 = C2V2 or C1Q1 = C2Q2, where
C – Concentration
V – Volume
Q – Quantity
Question 8 The formula calls for use of ethanol 10mls of 75%v/v; in stock there is
ethanol 95%v/v

Procedure
1. Calculation
C1V1 = C2V2
C1 = 95%, V1 =?, C2 = 75%, V2 = 10mls
95 X V1 = 10 x 75
V1 = 7.9mls of ethanol 95% v/v
2. Working formula for ethanol 75% solution
Ethanol 95% v/v 7.9mls
Purified water 2.1mls
3. Picked and cleaned equipments: measuring cylinder, stirring rod, beaker, pipette,
packaging bottle
4. Inverted the equipments to drain water
5. Measure 7.9mls of alcohol 95% and 2.1mls of purified water
6. Mix together
7. Pack the product in an appropriate
Question 9 Ethanol 70% is available in stock.
a) Determine the working formula for preparing 50mls of 1 in 20
dilute ethanol solution
b) Prepare the product
c) Write a label for the product

Determine working formula

1. Converting 1:20 to percentage
=
2. Formula to be used C1V1 = C2V2
C1 = 70%, V1 =?, C2 = 5%, V2 = 50mls
70 x V1 = 50 x 5
V1 =
3. Working formula for ethanol 5% (1:20) solution
Ethanol 70% 3.6mL
Distilled water to 50mL
4. Picked and cleaned equipments: measuring cylinder, stirring rod, beaker, pipette,
packaging bottle
5. Inverted the equipments to drain water
6. Accurately measured 3.6ml of ethanol 70% solution using pipette
7. Tarred a packaging bottle to 50mL
8. Transferred the ethanol 70% solution to tarred bottle
Solutions 45

9. Added distilled water to measuring until mark

10. Closed the container and agitated to obtain homogenous solution
11. Ensure clean working area, no spillages observed
12. Polished the bottle
13. Labelled the product
50ml
For external used only
Ethanol 5% solution
Use as directed by physician
Ingredients
Ethanol 5%

Manufacture date : date of practical

Expiry date :
Batch Number :
Store in cool dry place away from direct sun light
Keep out of reach of children
Discard the remaining after use
Name of manufacturer
Registration Number
Address Name of school - Pharmacy Lab P.O
Box, 724, Fort Portal
46 General Pharmacy Practical Manual

Question 10 Prepare 50 mL alcoholic stock solution such when 10mL is diluted to 500
yields the following
Ethanol 70% 0.8%
Hydrogen peroxide 3% 0.15%
Egg yellow 0.2g
Boiled and cooled water qs
a) Develop a working formula
b) Write method of preparation
c) Write a label for the product

Develop working formula

1. This involves dilution calculations
2. For Ethanol
C1V1 = C2V2
C1 = 0.8%, V1 = 500mL, C2 =?, V2 = 10mL
0.8 x 500 = C2 x 10ml
C2 = = 40%;
But 10ml has same concentration as 50mL
= x 50 = 20mL of ethanol required
3. For hydrogen peroxide
C1V1 = C2V2
C1 = 0.15%, V1 = 500mL, C2 =?, V2 = 10mL
0.15 x 500 = C2 x 10ml
C2 = = 7.5%;
But 10ml has same concentration as 50mL
= x 50 = 3.8mL
4. For egg yellow
Q1V1 = Q2V2
Q1 = 0.2g, V1 = 500ml, Q2 =?, V2 = 50ml
0.2 x 500 = 50Q2
Q2 =2g
5. Working formula
Ethanol 70% 20mL
Hydrogen peroxide 3% 3.8mL
Egg yellow 2g
Boiled and cooled water 50mL
Method of preparation
 Solutions 47

Question 11 Prepare 100mL of the cetrimide and chlorhexidine solution for use as
hand wash, such that when 10mL is diluted to 1Litre forms the following
Cetrimide BP 0.1%
Chlorhexidine BP 0.01%
Egg yellow color 1g
Ethanol 90% qs
a) Develop a working formula
b) Write method of preparation
48 General Pharmacy Practical Manual

Question 12 In stock you have 500mls of Formalin 37%. The concentration

recommended for preservation of anatomical structures is 10%.
Write the working formula and method of preparation of 100 bottles of
100mL Formalin 10%
 Solutions 49

Question 13 Prepare 120 mls of ammonium chloride mixture BP and sent the product
to Joviah for use 10mls tds for 3 days
Ammonium chloride 10g (1 in 2.7)
Ammonium solution 50ml
Peppermint emulsion 100ml
Purified water to 1000ml
NOTE: as the ammonium solution has bad smell; should added in tarred
bottle
50 General Pharmacy Practical Manual: By M. Wilson and L. Brian

Question 14 Develop a working formula for 100ml of zinc sulfate and zinc chloride
mouthwash BPC and prepare the product
Zinc sulfate 20 g
Zinc chloride 10 g
Dilute hydrochloride acid 10 ml
Compound tartrazine solution 10 ml
Chloroform water to produce 1000 ml
Hint: made by dissolving Zinc sulfate and Zinc chloride in a small
quantity of Chloroform solution. To this is added dilute hydrochloric acid
and compound tartrazine solution and the final volume is made up of
water.
 olutions 51

Question 15 Prepare 20ml of gentian violet Bp.

Gentian violet 10g
Alcohol 95% 100ml
Purified water qs to 1000ml
Hint: Dilute the alcohol with 800ml 0f purified water, dissolve the
gentian violet by agitation and add sufficient of purified water to 1000ml
52 General Pharmacy Practical Manual

Question 16 Prepare 100mls of alcoholic Iodine Solution BP- Cutaneous Solution

Iodine 25 g
Potassium Iodide 25 g
Purified Water 25 mL
Ethanol (90 per cent) to 1000 mL
Hint: Dissolve the Potassium Iodide in water, add the Iodine. Add
sufficient Ethanol (90 per cent) to produce 1000 mL.
 Solutions 53

Question 17 Hand sanitizer

Hand sanitizer for external use only and to help prevent the spread of germs. Components
include
 Isopropyl alcohol 99%, Spirit 95% (ethanol 95%)
 Gels like glycerine or aloe vera gel - used as humectant
 Hydrogen peroxide - used to inactivate contaminating bacterial spores
 Perfume or essential oils (clove, eucalyptus, peppermint etc)
 Distilled water or cold boiled water
For gel sanitizers, no distilled water or cold boiled water is added – the ratio of alcohol to gel
is 2:1. For spray sanitizers, distilled water or cold boiled water is added. The concentration of
ethanol or isopropyl alcohol should not be below 80%
Formula
Ethanol 96% 83mls
Hydrogen peroxide 4mls
Glycerol 1.8 mls
Eucalyptus oil 1ml
Cold boiled water to 100mls
Note: The volume of 83ml of ethanol 96% is calculated by alligation to obtain 80% ethanol
Procedure
1. Equipment‟s: packaging bottles, mixing stick, beaker, measuring cylinder,
alcoholmeter
2. Measure the reagents ethanol 96%, hydrogen peroxide and glycerol
3. Add glycerol (glycerol is very viscous rinse with some alcohol)
4. Add hydrogen peroxide
5. Add the alcohol into the beaker
6. Mix or stir to obtain homogenous mixture
7. Transfer the mixture into tarred bottle
8. Rinse beaker with boiled water and add to rinsing‟s to tarred bottle
9. Measure 1ml of eucalyptus oil and add to the bottle
10. Add cold boiled water to mark
11. Shake to obtain homogenous mixture
12. Label the bottle
54 General Pharmacy Practical Manual

Question 18 Linctus‟s are viscous liquid preparation used in treatment or relief of

cough, with syrup as the vehicle
Prepare 50 mls of simple linctus BP:
Note: Simple Linctus is an oral solution containing 2.5% w/v of Citric
Acid Monohydrate in a suitable vehicle with an peppermint flavor
 olutions 55

Question 19 Develop a working formula for 250mL of sodium chloride compound

mouthwash BP and write the method of preparation
56 General Pharmacy Practical Manual

SUSPENSIONS

1. Define suspensions
Suspensions are liquid preparations that consist of finely divided insoluble solid
particle (disperse phase) dispersed throughout fluid or continuous phase or
dispersion medium
Some suspensions are prepared and ready for use, while others are prepared as solid
mixtures intended for constitution just before use with an appropriate vehicle.
Examples include
 Antacid mixtures
 Dry powders for suspension (antibiotic)
 Analgesic oral suspension
 Enemas
 Topical suspension like lotions (calamine), ear drops
 Anthelmintic suspension
 Protamine Zinc-Insulin suspension
 Parenteral suspensions: benzyl penicillin suspension

2. List the ideal properties of suspensions

 Slow particle sedimentation rate
 Particles should be easily be re-dispersed
 Physically and chemically stable
 Small particle size
 Easily removed from the container

3. List advantages and disadvantages of suspension

Advantages
 Useful drug delivery system for therapeutic agents that have a low solubility
 Easily mask unpleasant/ bitter taste of drug
 Easy to swallow in pediatrics patients
 Can be formulated as controlled drug delivery
Disadvantages
 Highly unstable due to sedimentation; must be shaken prior to measuring a
dose
 Difficult to formulate
 Bulky to carry by patients
 Difficult to measure an accurate dose

4. List the label requirements of suspension

 “Shake the bottle before use” should be included
 Others requires resemble those of solutions
 Suspensions 57

5. List the composition of suspension

 Suspending agents: help active pharmaceutical ingredients to stay suspended
into the suspension. Examples include acacia, methylcellulose,
carboxymethylcellulose, sodium alginate, etc
 Solvents
 Flavoring agents
 Buffers
 Coloring agents
 Sweetening agents
 Antioxidants

6. You provided with the following products

A. Albendazole suspension
B. Amoxicillin powder for reconstitution
C. Chloramphenicol suspension
D. .
E. .
Identify the dosage forms
How would advise patients going to use the products
State the packaging and storage of the products

Extemporaneous preparation of suspension

The procedure of preparation follows almost the same steps as in solutions with the
exception of addition suspending. General method of preparation of suspensions include the
following steps
1. Write out the formula either from the prescription (unofficial) or from an official
text (official).
2. Calculate the quantities required for each ingredient in the formula to produce the
required final preparation.
3. Check the solubilities, in the vehicle, of all solids in the mixture. Use BP or BPC
4. Calculate the quantities of vehicle required to dissolve any soluble solids.
5. Weigh all solids on a Class II or electronic balance.
6. Dissolve all soluble solids in the vehicle in a small glass beaker using the same
procedures as in solutions.
7. Mix any insoluble diffusible powders in a porcelain mortar using the „doubling-up‟
technique to ensure complete mixing
8. OR mix any insoluble indiffusible powders and the suspending agent in a porcelain
mortar using the „doubling-up‟ technique for complete mixing
9. Add a small quantity of the vehicle (which may or may not be a solution of the
soluble ingredients) to the solids in the mortar and mix using a pestle to form a
smooth paste.
10. Add further vehicle in small quantities, and continue mixing until the mixture in the
mortar is of a pourable consistency.
11. Tare final packaging bottle using purified water
12. Transfer the contents of the mortar to tarred packaging bottle.
58 General Pharmacy Practical Manual

13. Rinse out the mortar with more vehicle and add any rinsing‟s to packaging bottle.
14. Add remaining liquid ingredients to the mixture (volatile )
15. Make up to final volume with vehicle and shake
16. Polish and label , dispense to the patient
The 'doubling-up’ technique
1. Weigh the powder A and powder B and place on labeled weighing paper.
2. Add approximately the same amount of powder A and powder B, to the mortar or
piece of paper
3. Mix well with pestle or spatula
4. Continue adding an equal amount of powder A and B mix with the pestle, doubling
the amount of at each addition until all powder is used.
NOTE: The labeling requirements “shake the bottle well before use
Shake the bottle well before use
Quantity
Name of the product
Directions of use
Ingredients in 5 mls
Manufacture date : date of practical
Expiry date :
Batch Number :
Name of patient :
Store in cool dry place away from direct sun light
Keep out of reach of children
Discard the remaining after use
Name of manufacturer
Registration Number
Address Name of school - Pharmacy Lab P.O
Box, 724, Fort Portal

Question 1 You are provided with the following master formula for
Magnesium Trisilicate mixture BP
Master formula
Magnesium trisilicate 50g
Light magnesium carbonate BP 50g
Sodium bicarbonate BP 50g
Concentrated peppermint emulsion 25mls
Double strength chloroform water BP 500ml
Portable water to produce 1000ml
a) Develop a working formula for preparing 4 bottles of
100ml each of Magnesium Trisilicate mixture BP
b) Write a method of preparation
c) Write a label for the product and send one bottle to Ritah –
Harugongo to use 10mls TDS for 3 days
 Suspensions 59

Develop a working formula

1. Quantity to be prepared:
= number of bottles x quantity in each
= 4 x 100 = 400mL
2. Calculations
Magnesium trisilicate = x 50 = 20g
Light magnesium carbonate = x 50 = 20g
Sodium carbonate = x 50 = 20g
Peppermint emulsion = x 25 = 10mls
DS Chloroform water = x 500 = 200mls
3. Working formula
Magnesium trisilicate 20g
Light magnesium carbonate 20g
Sodium bicarbonate BP 20g
Concentrated peppermint emulsion 10mls
Double strength chloroform water BP 200mls
Portable water to produce 400mls
4. Determining initial volume to dissolve in soluble sodium bicarbonate
Solubility of sodium bicarbonate 1 in 11
1g dissolves in 11mls
20g will dissolve in = 20 x 11 = 220mls
Will use 250mls initially (220mls of DS Chloroform water and 30mls of purified
water)
Method of preparation
Weighing and measuring of ingredients
5. Cleans the weighing scale and working area
6. Protects the weighing scale
7. Balances the weighing scale to zero
8. Accurately weighed 20g of light magnesium carbonate, 20g of magnesium trisilicate,
20g of sodium carbonate using a weighing scale
9. Accurately measured 20mls of peppermint using measuring cylinder
10. Accurately measured about 30mls of distilled water and 220mls of DS chloroform
water using a measuring cylinder
11. No spillages on the pan of weighing scale and during measuring
12. Labels weighed and measured ingredients with name and quantity
13. Returned the weights back to zero after weighing
14. Maintains a clean environment
Procedure of preparation
15. Clean the working area
16. Picked and cleaned the equipments: beaker, measuring cylinder, stirring rod,
packaging bottles,
17. Inverts the equipments to drain any excess water
18. Mixed magnesium trisilicate and light magnesium carbonate
19. Transferred a portion of magnesium trisilicate to piece of paper
20. and added portion of light magnesium carbonate and mix till evenly distributed using
the doubling up technique or mortar could be used instead of paper for mixing
21. Transfers the measured 30mls distilled water and to beaker and 220mls of DS
chloroform water into beaker
22. Add sodium bicarbonate to beaker
23. Stirred until dissolved
24. Transfer the powder mixture into a beaker or mortar. Added the sodium bicarbonate
solution and mixed well to make a smooth paste
25. Add more solution until the solution is pourable and transferred to a 500ml measuring
cylinder
26. Transferred the measured peppermint into 500ml measuring cylinder
27. Rinsed the beaker or mortar with 20mls of purified water and transferred the rinsing‟s
to 500ml measuring cylinder
28. Topped to volume (400ml mark) and stirred to ensure complete mixing
29. Packed 90mL in 4 bottles
30. Maintained a clean area
31. Polished the bottle
Write label
Shake the bottle well before use
100mL
Magnesium Trisilicate mixture BP
Use 10mls three time a day for 3 days
Ingredients (each 5mls contains)
Magnesium trisilicate :
Light magnesium carbonate :
Sodium bicarbonate BP :
Conc peppermint emulsion :
DS chloroform water BP :
Manufacture date : date of practical
Expiry date :
Batch Number :
Name of patient : Ritah – Harugongo
Store in cool dry place away from direct sun light
Keep out of reach of children
Discard the remaining after use
Name of manufacturer
Registration Number
Address Name of school - Pharmacy Lab P.O
Box, 724, Fort Portal
 Suspensions 61

Question 2 You are provided with the following master formula for chalk mixture
pediatric BP
Calcium carbonate BP 20g
Tragacanth BP 2g
Concentrated cinnamon water 4ml
Syrup BP 100ml
Double strength chloroform water 500ml
Portable water to 1000ml
a) Develop working formula for preparing 100ml of chalk mixture
pediatric BP
b) Write a method of preparation
c) Write a label for product

Develop a working formula

1. Quantity to prepare 100ml
2. Calculation
Calcium carbonate BP = 20 = 2g
Tragacanth BP = 2 = 0.2g
Conc cinnamon water = = 0.4mls
Syrup BP = = 10mls
DS chloroform water = = 50mls
3. Working formula
Calcium carbonate BP 2g
Tragacanth BP 0.2g/200mg
Concentrated cinnamon water 0.4mls
Syrup BP 10mls
Double strength chloroform water 50mls
Portable water quantity sufficient to 100mls
Method of preparation
Weighing and measuring of ingredients
4. Cleans the weighing scale and working area
5. Protects the weighing scale
6. Balances the weighing scale to zero
7. Accurately weighed 2g of Calcium carbonate, 0.2g of tragacanth using a weighing
scale
8. Accurately measured .4mls of cinnamon water using a pipette
9. Accurately measured 10mls of syrup using measuring cylinder
10. Accurately measured 50mls of DS chloroform water using a measuring cylinder
11. No spillages on the pan of weighing scale and during measuring
12. Labels weighed and measured ingredients with name and quantity
13. Returned the weights back to zero after weighing
14. Maintains a clean environment
 62 General Pharmacy Practical Manual

Procedure of preparation
15. Clean the working area
16. Picked and cleaned the equipments: motor, pestle, beaker, measuring cylinder, stirring
rod, packaging bottle
17. Mixed chalk and tragacanth using a piece of paper by doubling technique
18. Transferred the mixture to motor
19. Added syrup and mixed with pestle to make a smooth paste
20. Added DS Choroform water while mixing until pourable paste is formed
21. Tarred a packaging bottle to 100ml
22. The paste is transferred to a tarred bottle
23. Rinsed the mortar with part of DS Chloroform water and transferred the rinsing‟s to
tarred bottle
24. Added cinnamon water to a tarred bottle
25. Top up with remaining DS Chloroforms water and portable water to 100ml.
26. Polished the bottle
27. Maintained a clean working area
Writing a label

Shake the bottle well before use

100mL
Chalk mixture BP
Use as directed by physician
Ingredients (each 5mls contains)
Calcium carbonate :
Tragacanth BP :
Manufacture date : date of practical
Expiry date :
Batch Number :
Store in cool dry place away from direct sun light
Keep out of reach of children
Discard the remaining after use
Name of manufacturer
Registration Number
Address Name of school - Pharmacy Lab P.O
Box, 724, Fort Portal
 Suspensions 63

Question 3 Prepare 150ml of Magnesium Carbonate Mixture BPC

Master formula
Light Magnesium Carbonate 50 g
Sodium Bicarbonate 80 g
Peppermint Emulsion 25 mL
DS Chloroform Water BP 500 mL
Purified water to 1000 mL
64 General Pharmacy Practical Manual

Question 4 Prepare 100ml of Kaolin Mixture Pediatric BP

Light Kaolin 200 g
Raspberry Syrup 200 mL
Benzoic Acid Solution 20 mL
Amaranth Solution 10 mL
DS Chloroform Water 500 mL
Purified Water to 1000 mL
 Emulsions 65

EMULSIONS

1. Define emulsions
Emulsions are biphasic systems consisting of immiscible liquids, one which is finely
subdivided and uniformly distributed as droplets (internal phase) throughout the other
(continuous/ external phase) and system is stabilized by the presence of an emulsifying
agent.

2. List the types of emulsions

 Oil-in-water emulsion: where oil is the dispersed phase and an aqueous solution
is the continuous phase
 Water-in-oil emulsion: where water or an aqueous solution is the dispersed
phase and oil material is the continuous phase.

3. List the components of emulsions

 Emulsifying agents: stabilize emulsion and prevent coalescence, the merging of
droplet
 Vehicle: water and oil
 Preservative
 Sweetening agents
 Coloring agents

Extemporaneous preparation of emulsions

Methods of preparation of emulsion include the following
 Dry gum method
 Wet gum method
 Continental method
Labeling requirements „Shake the bottle well before use‟ and „for internal use only‟, „for
external use only‟ depending on the type
Note: Care must be taken during preparation as the product may crack
The preparation of emulsions has two steps
1. Preparation of primary emulsion (concentrate)
2. Dilution of the concentrate
General method of preparation of an emulsion using the dry gum method
1. Clean, dry equipment – All equipment should be thoroughly cleaned, rinsed with
water and dried carefully before use, particularly measures, mortars and pestles.
2. Accurately weigh the quantities. Ingredients for the primary emulsion should all be
weighed and measured before starting to make the product
3. Correct rate and order of addition of ingredient is important.
4. Preparation of a concentrate called the „primary emulsion‟.
5. Dilution of the concentrate
66 General Pharmacy Practical Manual

Examples of oils used in emulsions

Oil Examples
Fixed Arachis, castor, Cod Liver, cotton seed and maize oils
Mineral Liquid Paraffin, Turpentine oil
Volatile Cinnamon & peppermint Oil
Ratio of ingredients in the primary emulsion
Oil Ratio
Oil Water Gum
Fixed 4 2 1
Mineral 3 2 1
Volatile 2 2 1
Preparation of the primary emulsion
1. Measure the oil accurately in a dry measure, aqueous vehicle (water) and weigh the
gum
2. Transfer the oil into a large dry porcelain mortar, add the gum and mix lightly with the
pestle, just sufficient to disperse any lumps
3. Add all of the required aqueous vehicle in one addition. Then mix vigorously, using the
pestle with a shearing action in one direction.
4. When the product becomes white and produces a „clicking‟ sound the primary emulsion
has been formed. The product should be a thick white cream.
Dilution of the primary emulsion
1. Dilute the primary emulsion with very small volumes of the remaining aqueous vehicle.
Mix carefully with the pestle in one direction.
2. Transfer emulsion to a measure, with rinsing‟s. Add other liquid ingredients if
necessary and make up to the final volume.
NOTE: Most emulsions are prepared extemporaneously

Question 1 Provided with the following formula.

Cod liver oil 40 mL
Acacia qs
Flavor 1mL
Freshly boiled/ cooled water to 100 mL
Calculations for quantities in the primary emulsion

Calculations
1. Cod liver oil is fixed oil
2. Ratio for primary emulsion oil for fixed oil: Water: Gum = 4: 2: 1
3. Quantity of oil (cod liver oil) = 40mL representing 4parts
4. Quantity of gum (in grams)
4parts of oil represent 40mL
1part of gum will be
Quantity of gum = 10g
 5. Quantity of water (mLs)
4parts of oil represent 40mL
2parts of water will be
Quantity of water = 20mLs
6. Working formula for primary emulsion
Cod liver oil 40 mL
Acacia 10 g
Freshly boiled/ cooled 20 mL
Question 2 The following formula for preparing and an emulsion
Arachis oil 40ml.
Acacia BP qs
Peppermint emulsion 4ml
DS chloroform water 50ml
Freshly boiled & cooled water 100mls
a) Determine the formula for primary emulsion and general
formula for the product
b) Write the method of preparation of product
c) Write a label of the product

Develop working formula

1. Arachis oil is fixed oil
2. Ratio for primary emulsion oil for fixed oil: Water: Gum = 4: 2: 1
3. 4 parts of arachis oil are equal to 40mls
4. Quantity of gum (g) =
5. Quantity of aqueous phase (water) in ml =
6. Working formula for primary emulsion
Arachis oil 40mls
DS chloroform water 20mls
Acacia gum 10g
7. Working formula for the product
Arachis oil 40ml.
Acacia BP 10g
Peppermint emulsion 4ml
DS chloroform water 50ml
Freshly boiled & cooled water 100mls
Method of preparation
Weighing and measuring of ingredients
8. Cleans the weighing scale and working area
9. Protects the weighing scale
10. Balances the weighing scale to zero
11. Accurately weighed 10g of acacia using a weighing scale
12. Accurately measured .40mls of arachis oil using measuring cylinder
13. Accurately measured 4mls of peppermint emulsion
14. Accurately measured 50mls of DS chloroform water using a measuring cylinder
15. No spillages on the pan of weighing scale and during measuring
68 General Pharmacy Practical Manual

16. Labels weighed and measured ingredients with name and quantity
17. Returned the weights back to zero after weighing
18. Maintains a clean environment
Procedure of preparation
19. Clean the working area
20. Picked and cleaned the equipments: motor, pestle, measuring cylinder, stirring rod,
packaging bottle
21. Inverts the equipments to drain the water. Dries the motor with clean dry cloth
Primary emulsion
22. Transfer arachis oil BP to a dry clean porcelain motor
23. Add acacia gum to motor
24. Gently mix to disperse the any lumps
25. Add 20mls of DS chloroform water at ago
26. Stirs with a pestle in one direction vigorously until the mixture thickens
27. Continues to stir form a primary emulsion with characteristic clicking sound
Dilution of primary emulsion
28. Add 10mls double strength chloroform water to make the formulation pourable
29. Transfer the primary emulsion into a tarred bottle
30. Rinsed the motor with the remaining chloroform water and add into the tarred bottle.
31. Measure 4mls of concentrated peppermint emulsion and add into the tarred bottle
32. Top up with purified water to 100mls and shake
33. Polished the product.
Label
Shake the bottle well before use
100mL
The emulsion
Use as directed by physician
Ingredients (each 5mls contains)
Arachis oil :
Acacia :
Manufacture date : date of practical
Expiry date :
Batch Number :
Patient name :
Store in cool dry place away from direct sun light
Keep out of reach of children
Discard the remaining after use
Name of manufacturer
Registration Number
Address Name of school - Pharmacy Lab P.O
Box, 724, Fort Portal
 Emulsions 69

Question 3 Prepare 50mls of liquid paraffin BP 30% emulsion for Ivan – Fort Portal to
use 10mls BD for 3 days
Liquid paraffin Bp 15mls
Acacia powder qs
Peppermint emulsion 2mls
Purified water to 50mls
70 General Pharmacy Practical Manual: By M. Wilson and L. Brian

Question 3 Prepare 100mL of Cod Liver Oil emulsion from a doctor's prescription
Cod Liver Oil 30 mL
Acacia qs
DS Chloroform Water 50 mL
Freshly boiled/ cooled water to 100 mL