Topical -Base Flashcards
What makes up the base or vehicle x3
Oils and greases
Liquids
Powders
Types of bases x5
Creams
Ointments
Lotion
Gel
Foam
Solid
Solution
Paste
Define emulsifier
A substance that reduces surface tension at the interface of 2 normally immiscible phases or substances allowing them to mix and form a homogenous emulsion
Function of ointments x5
Reduce transdermal water loss
Increase epidermal barrier function
Soften dry skin
Ease itching
Reduce scaling
When can ointments be used x2
Eczema, dry skin
Prevention of frost bites
What is ointment made of x3
Hydrocarbon
Wool fat ie lanolin
Vegetable oil
Disadvantages of ointments x5
Sticky
Occlusive > pomade acne
Sunburn, acts as magnifier
Difficult to wash off
Infection from trapped microorganisms
Describe oil in water creams x2
They are hydrophilic, outer phase is aqueous
Easily washable
Describe the water in oil creams x2
Lipophilic, outer phase is fatty
Better drug absorption
When can o/w cream be used x4
Eczema
Oozing impetigo
Normal skin
Fatty skin
Purpose of w/o creams
Transport of lipophilic or hydrophobic drugs making it easier to release them
W/O creams are less suitable for x2
Wet dermatitis
Tropical conditions because they are prone to microbial contamination
Describe two types of lotions
Shaken- powder in a water base
Diluted cream- water added to a cream
What causes the cooling effect of shake lotions
When water evaporates it leaves behind the inert powder on the skin
