3 - Moisturisers

Question 1

Moisturisers function to:

(1) retard transepidermal water loss from a damaged epidermal barrier
(2) to soothe irritated skin
(3) to increase skin softness by filling the irregular spaces left by desquamating corneocytes

Answer 1

True (in contrast to emollients which simply make the skin smooth and soft)

Question 2

Moisturisers increase the water content of the epidermis and stratum corneum

Answer 2

True (in contrast to emollients which simply make the skin smooth and soft)

Question 3

Moisturisers that rehydrate the stratum corneum can be classified as:

(1) occlusives
(2) humectants

Answer 3

True (in contrast to emollients that simply make the skin smooth and soft)

Question 4

Occlusive moisturisers function to condition the skin by impairing evaporation of water to the atmosphere

Answer 4

True

Question 5

Occlusive moisturisers are generally oily substances through which water cannot easily pass

Answer 5

True

Question 6

Occlusive moisturisers can be classified into 10 categories:

(1) hydrocarbon oils and waxes - petrolatum, mineral oil, paraffin, squalene

Answer 6

True

Question 7

Occlusive moisturisers can be classified into 10 categories:

(2) silicone oils - dimethicone, cyclomethicones

Answer 7

True

Question 8

Occlusive moisturisers can be classified into 10 categories:

(3) vegetable and animal fats - soybean oil, olive oil, lanolin and animal fats

Answer 8

True

Question 9

Occlusive moisturisers can be classified into 10 categories:

(4) fatty acids - lanolin acid, stearic acid

Answer 9

True

Question 10

Occlusive moisturisers can be classified into 10 categories:

(5) fatty alcohol - lanolin alcohol, cetyl alcohol

Answer 10

True

Question 11

Occlusive moisturisers can be classified into 10 categories:

(6) polyhidric alcohols - propylene glycol alcohols

Answer 11

True

Question 12

Occlusive moisturisers can be classified into 10 categories:

(7) wax esters - lanolin, beeswax, stearyl stearate

Answer 12

True

Question 13

Occlusive moisturisers can be classified into 10 categories:

(8) vegetable waxes - carnauba, candelilla waxes

Answer 13

True

Question 14

Occlusive moisturisers can be classified into 10 categories:

(9) phospholipids - lecithin

Answer 14

True

Question 15

Occlusive moisturisers can be classified into 10 categories:

(10) sterols - cholesterol

Answer 15

True

Question 16

Humectants are substances that attract water, mimicking the role of dermal glycosaminoglycans such as hyaluronic acid

Answer 16

True

Question 17

The most commonly used humectants are:
(1) glycerin
(2) propylene glycol
as they function both as humectants and as vehicles in many moisturisers

Answer 17

True (other humectants include honey, sodium lactate, urea, sorbitol, pyrrolidine carboxylic acid, gelatin, hyaluronic acid and vitamins A/B5/C)

Question 18

Urea is the most common humectant as the active ingredient, and the amount of humectant properties provided is directly related to the concentration of the ingredient

Answer 18

True

Question 19

Topically applied humectants draw water largely from the dermis to the epidermis and rarely from the environment under conditions in which the ambient humidity exceeds 70%

Answer 19

True (however under low humidity conditions, humectants such as glycerin draw moisture from the skin and increase transepidermal water loss; which is the reason why humectants must be used in combination with occlusives)

Question 20

Water applied to the skin in the absence of a humectant is rapidly lost to the atmosphere, however skin well hydrated after soaking retains water more efficiently if humectants are subsequently applied

Answer 20

True

Question 21

Humectants are always used in combination with occlusives as humectant draw the water from the dermis to the dehydrated stratum corneum and epidermis, while the occlusives trap the water in the skin thereby preventing evaporation and rehydrates the skin

Answer 21

True (as under low humidity conditions, humectants draw moisture from the skin and increase transepidermal water loss)