Lec 7 Topical Products

Question 1

What are the 4 types of semi-soilds?

Answer 1

• Ointment
• Cream
• Paste
• Gel

Question 2

What is an ointment?

Answer 2

• Semi-soild greasy preparation intended for external app. to the skin
• Act as a physical barrier to environment’
• Act as emollient: soothe, smooth and hydrate skin
• Low risk of irritation and sensitization

Question 3

What is a cream?

Answer 3

Semi-solid emulsion which the active is either dissolved or dispersed

o/w= non-occlusive
w/o= occlusive

Question 4

What is a gel?

Answer 4

A solid/semi-solid system with at least 2 constituents: a crosslinked polymeric structure interpenetrated by a liquid

Question 5

What is the difference between hydrogel and organogel?

Answer 5

Hydrogel= semi-solid formulation having an external polar solvent phase immobilized within a 3-D network structure

Organogel= semi-solid formulation having an external organic solvent phase, immobilized within a 3-D network structure

Question 6

What is a paste?

Answer 6

• Ointment containing as much as 50% powder dispered in a fatty base
• High viscosity (localise effect of irritant)
• Less greasy than ointment as powder absorbs some of the fluid hydrocarbon

Question 7

What is a niosome?

Answer 7

Hydrophilic ends point outwards
Hydrophobic ends face each other to form the bilayer

draw diagram

Question 8

What are the advantages of niosomal topical products?

Answer 8

• enhance permeability of drug
• control the release of ingredients
• protect drug from degradation
• better stability and lower cost compared to Liposome products

Question 9

What is the difference between a liposome and niosome?

Answer 9

Liposome= both ends of the bilayer are hydrophobic

Niosome= bilayer is hydrophilic and hydrophobic