Semisolid : Ointment/Bases Flashcards
1
Q
Oleaginous Bases
A
- Hydrophobic
- Has emollient effect
- Difficult to wash with water
- Greasy and stain clothing
- Mineral oil is levigating agent.
- Occlusive: prevent the escape of water
- Do not dry out or change on aging
- Retained on the skin for long periods
2
Q
Oleaginous Bases
A
1-Petrolatum USP ( Vaseline).
2-White Petrolatum USP ( White Vaseline).
3-Yellow Ointment USP (simple ointment).
4-White Ointment USP.
3
Q
ABSORPTION BASES
A
1- Anhydrous Absorption Bases - absorb water to become w/o emulsion
2- (Hydrous Absorption Bases) (w/o) - can absorb more water
4
Q
1- Anhydrous Absorption Bases
A
- Emollient
- Occlusive
- Anhydrous
- Absorbs water
- Not water washable
- Greasy and stain clothing
e. g. Hydrophilic Petrolatum
e. g. Anhydrous Lanolin ( Lanolin USP)
5
Q
2- (Hydrous Absorption Bases) (w/o)
A
- Emollient
- Occlusive
- Contain water to start with
- Absorb additional water
- Greasy and stain clothing
• Examples:
- Hydrous Lanolin
- Cold cream(cleansing creams)
– Commercially Eucerin & Nivea cream
6
Q
WATER REMOVABLE BASES
A
- O/W emulsions
- Also called “Water-washable Bases” creams.
- External phase is water
- Easily water washable bases.
- Can be diluted with water or aqueous solutions.
- Non greasy
- Must be preserved
- Cosmetically elegant.
- Hydrophilic ointment is an example
7
Q
WATER SOLUBLE BASES
A
- Contain only water soluble components
- May include gelled aqueous solutions
- Water washable, lipid free, greaseless
- No oleaginous component
- for non-aqueous or solid substance incorporation.
- Non-occlusive and may dehydrate SC
- High drug solubility in the base may lead to poor bioavailability.
- Major component is PEG (polyethylene glycol)
- Example : PEG ointment NF
8
Q
Incorporation
A
- “mix together”. For insoluble drugs
- Utilize trituration, then levigation to form a paste
- Levigating Agents : mineral oil, glycerin or propylene glycol.
9
Q
Levigating Agents
A
- Mineral oil is the best choice for oleaginous bases.
- Water soluble or miscible levigating agents are: Water, glycerin, alcohol, or propylene glycol.
- Oil soluble levigating agent is Mineral oil.
10
Q
Fusion
A
- Melting, mixing , cooling , congealing.
- Heat sensitive and volatile substances are added last.
- Solutions and levigated solids may be added to the congealed base.
- In porcelain dish or beaker, industry: steel-jacketed kettles.
11
Q
Creams
A
- one or more medicinal agent dissolved or dispersed in either a w/o emulsion or an o/w emulsion or water washable bases.
- Topical, vaginal, rectal creams…
- Easier to spread and easier to remove than ointments
- Pharmaceutical creams are classified as waterremovable bases in the USP and are described under Ointments.
12
Q
Vanishing Cream: o/w emulsion
A
- containing large percentage of water and stearic acid or other oleaginous components
- upon application water evaporates leaving a thin residue film of the stearic acid or other oleaginous component.
13
Q
Cold Cream
A
- w/o emulsion
- Ex : Pond’s Cold cream ( make up removal )
14
Q
Gels
A
- a semisolid being either a suspension of small inorganic particles or a large organic molecule interpenetrated in a liquid medium.
- Rendered jelly like by the addition of a gelling agent.
- Not tacky
- Spread readily
- Easily removed from skin
- Most are clear patient compliance
15
Q
Gelling Agents
A
- Cellulose derivatives such as methylcellulose, hydroxypropyl methylcellulose (HPMC),and other derivatives
- Polysaccharides(natural) such as xanthan gum ,tragacanth, alginates, and carrageenan.
- Acrylic polymers(synthetic) such as Carbomer that form gels at concentrations as low as 0.5%.
- Colloidal dispersed solids such as silica and clays.
