3. Creams

Question 1

What is the definition of cream according to Ansel’s?

Answer 1

A semi-solid dosage form containing one or more drug substances dissolved or dispersed in a suitable base and are generally intended for external application to the skin or mucous membrane.

Question 2

What is the definition of creams according to BP?

Answer 2

Creams are formulated to provide preparations that are essentially miscible with the skin secretion. They are intended to be applied to the skin or certain mucous membranes for protective, therapeutic or prophylactic purposes especially where an occlusive effect is not necessary.

Question 3

What are the types of creams?

Answer 3

Water in oil (W/O ) Emulsion (e.g. Cold Creams)
Oil in water (O/W ) Emulsion (e.g. Vanishing Creams)

Question 4

What are the formulative components of creams?

Answer 4

1. Antioxidants
2. Base
3. Buffer
4. Chelating agent
5. Emulsifying agent
6. Humectant
7. Permeation enhancer
8. Preservative
9. Fragrances

Question 5

Which antioxidant is used in creams?

Answer 5

Ascorbic acid

Question 6

Base

Answer 6

White petrolatum, lanolin, cholesterol

Question 7

Buffer

Answer 7

Citrate buffer, phosphate buffer

Question 8

Chelating agent

Answer 8

EDTA, Citric acid

Question 9

Emulsifying agent

Answer 9

Cetostearyl alcohol, detergent

Question 10

Humectant

Answer 10

Glycerin, PEG, Propylene glycol

Question 11

Permeation enhancer

Answer 11

Ethanol, PEG, Oleic acid

Question 12

Preservatives

Answer 12

Benzoic acid, phenyl ethyl alcohol

Question 13

Fragrances

Answer 13

Lemon oil, rose oil, lavender oil

Question 14

What are the methods of preparation of creams?

Answer 14

Trituration
Levigation
Fusion method

Question 15

Medicament

Answer 15

Molten base - cream
solid base - ointment

Question 16

Soluble powder

Answer 16

Fusion ; dissolve in base at the lowest temperature possible - cream
Trituration - ointment

Question 17

Insoluble coarse powder

Answer 17

Levigation - cream
Levigation with a small amount of solid base - Ointment base

Question 18

Insoluble fine powder

Answer 18

Incorporate in small amount by trituration and the base cools and thickens - creams
Trituration - Ointment bases

Question 19

Volatile liquid

Answer 19

Incorporate when the ointment has cooled to below 40 degree celcius by trituration -creams
trituration - ointment base

Question 20

Non-volatile liquid

Answer 20

Incorporate into molten base by trituration -creams
Trituration - ointment base

Question 21

Explain the “discard date” for creams.

Answer 21

Some official texts suggest that creams are given a four-week discard date.
This is significantly shorter than ointment(which is three months) because of the susceptibility of creams to microbial contamination.
Diluted creams would normally be given a two-week discard date.
Instead of “Expiry date” apply the term “Discard after” or “Do not use after” followed by the definite date or time.

Question 22

Explain the storage of creams

Answer 22

In large-mouth ointment jars or in metal or plastic tubes.
In well-closed containers to protect against contamination and in a cool place to protect against product separation due to heat.
When required light sensitive preparations are packaged in light resistant containers.

Question 23

Which labels are used for creams?

Answer 23

1. For external use only
2. For dermal use only
3. In addition to the usual labelling requirements for pharmaceutical products, the USP directs that the labelling for certain ointments and creams include the type of base used (e.g., water-soluble or water insoluble)

Question 24

What is the difference b/w cold cream vs. vanishing cream?

Answer 24

Cold cream:
1. Used as adhesive for makeup powders.
2. Reduces loss of moisture from dry skin.
3. Smoothens the skin and keeps it soft.
4. Prevents skins from roughening and chapping.

Vanishing cream:
1. Typically used to cleanse the face off makeup.
2. Heavily moisturizes dry skin.
3. Can also be used as a balm for dry cracked lips.
4. It can also be used as a shaving cream alternative for men.

Question 25

What are the advantages of creams?

Answer 25

1. Avoidance of first pass metabolism.
2. Convenient and easy to apply
3. Easier to spread and remove than Ointment
4. Easily water washable. Easy to wipe away.
5. Less greasy compared to ointment.
6. Suitable for sensitive, dry, and fair skin.
7. Suitable for acute lesions.

Question 26

What are the disadvantages of creams?

Answer 26

1. Skin irritation and contact dermatitis may occur due to hypersensitivity of the drugs and / or excipients
2. Poor permeability of some drugs through the skin
3. Possibility of allergic reactions
4. Can be used only for drugs which require very small plasma concentration for action
5. Enzyme in epidermis may denature the drugs
6. Drugs of larger particle size not easy to absorb through the skin.
7. Stability issues like caking and sedimentation.