Dermol Lotion

Question 1

This is an externally used oil-in-water emulsion, which takes the form of a lotion. Describe 2 benefits to the patient of this type of product compared with using a semi-solid.

Answer 1

Less greasy so patients find it more acceptable and provides rapid absorption and evaporation from skin

Question 2

Which 2 excipients are being used as emulsifying agents in this product, and to which broad category of emulsifying agent do they belong?

Answer 2

cetostearyl alcohol, macrogol cetostearyl ether both belong to Non-ionic synthetic and semi-synthetic surfactants

Question 3

This product can be used as a soap substitute to clean the skin, which excipients in the product enable this use and how?

Answer 3

Benzalkonium Chloride is primarily used as a preservative and antimicrobial agent, and secondarily used as a surfactant. It works by killing microorganisms and inhibiting their future growth

Question 4

What is “cracking” in reference to emulsions, and why is it important to avoid in medicines for patient use?

Answer 4

Cracking: two phases separate irreversibly with lower-density liquid (oil phase) floating on top of higher-density (water phase)
Drug is not evenly dispersed so not good for patient

Question 5

When making an oil-in-water emulsion by the dry gum method extemporaneously, why is it important to use a large mortar?

Answer 5

The primary emusion may not form but a thin liquid instead (insufficient shear)

Question 6

When making an oil-in-water emulsion extemporaneously you would normally make a primary emulsion first before it is diluted to volume with more of the continuous phase. Why is this?

Answer 6

the primary emulsion is a thick stable emulsion prepared using optimal proportions of ingredients, smaller droplets during mixing, thus assisting in creating a more stable emulsion