PHA 326: Topicals
USP Ointment classification
- Oleaginous or hydrocarbon bases
- Absorption bases
- Water-removable bases
- Water-soluble bases
Ointments can be:
- Medicated (used as vehicle)
- Non-medicated (used as emollient/lubricant)
- Pastes (large percentage of solid material)
Example of non-medicated ointment
Examples of oleaginous of hydrocarbon bases
- Petrolatum alone (petroleum)
- Petrolatum modified by waxes / liquid petrolatum (mineral oil)
Example of semisolid hydrocarbons
Example of solid hydrocarbon
- Vaseline (white / decolorized yellow petrolatum)
- paraffin wax
Oleaginous/hydrocarbon bases have _______ (bad/good) occlusive, emollient properties allowing them to lock moisture in.
Oleaginous/hydrocarbon bases are ____________, making them difficult to wash off
_________________ are w/o emulsion or anhydrous bases that convert to w/o emulsion
True/False: Absorption bases are occlusive (less so than hydrocarbons) and emollient.
True/False: Absorption bases are difficult to wash off.
Example of anhydrous absorption bases
Hydrophilic petrolatum (i.e. Aquaphor)
Example of w/o emulsion absorption bases
Lanolin (obtained from sheep wool)
What is Aquaphor made of?
- Cholesterol (30g)
- Stearyl alcohol (30g)
- White wax (80g)
- White petrolatum (860g)
Example of a semisolid absorption bases
What two components in cold cream combine to form a sodium soap?
Beeswax and sodium borate
o/w emulsion that easily washes off
Example of a product using water-removable bases
What are the preservatives in hydrophilic ointment?
What are the oleaginous components of hydrophilic ointment?
- Stearyl alcohol
- White petrolatum
What is the continuous phase in products with water-removable bases?
"greaseless" bases with water-soluble components.
Example of a water soluble base
Polyethylene glycol ointment (composed of PEG 3350 and PEG 400)
PEG 3350 is a ___________ at room temp
PEG 400 is a ____________ at room temp
If you wanted a polyethylene glycol ointment that was less viscous, how would you change the proportions of PEG 3350 and/or PEG 400?
Increase the proportion of PEG400
Reduce particle size by grinding (trituration) or by first incorporation a liquid/wetting agent (levigation or spatulation if ointment slab/spatula used)
Process of slowly adding powder to a solution to allow it to mix properly.
Process of heating and cooling (mix/melt); used for vaccine material
What are oinment mills used for?
You can create an emulsion by combining melted ___________ components and heated __________ components
Products applied topically must be free of ________________
- P aeruginosa
- S aureus
Products intended for rectal, urethral, or vaginal use should be tested for:
Evaluate need for preservatives in oinment bases using what?
Preservative efficacy test
True/False: All emulsions require an antimicrobial agent.
How large are ointment jars typically?
What are ointment tubes typically made out of?
- HDPE (High Density Polyethylene)
__________ are semisolid viscous emulsions of o/w or w/o type
Vanishing cream is ____ (o/w or w/o)
Vanishing cream is also known as _________
Which part of vanishing cream is melted?
- Cetyl alcohol
- Mineral oil
- Stearic acid
Which part of vanishing cream is heated?
- Pot. hydroxide
- Propylene glycol
- Purified water
Jelly like dispersions with the addition of a gelling agent
Examples of gels
- Hydroxyethylcellulose (HEC)
- PLO (pluronic lecithin organogel)
Isopropyl myristate is a ___________ enhancer in androgel
What is the neutralizing compound in androgel?
Card that tells you how much gel to use
As alcohol evaporates, particles remain dissolved in remaining liquid creating ___________
True/False: Androgel is considered very flammable because it contains a lot of alcohol.
How can a greasy product like vaseline help keep skin moist?
Locks in moisture
List the steps of gel preparation
- API mixed with co-solvent w/ part of the solvent
- Polymer added to walls of the vortex solvent mix
- API solution mix added to the polymer solution mix
- Neutralizer added to the final solution mix
- Gel formation after neutralization
These mixtures combine ingredients with different melting points, and result in the overall melting point of the mixture to change
Example of a eutectic mixture
Emla cream (lidocain and prolocaine mix)
Irritation testing involves a numerical score ranging from 0-4 where 0 indicates ______________ and 4 indicates _____________
No reaction; worst reaction
What kind of animal irritation testing is performed?
Draize dermal irritation tests on rabbits (shave back and observe)
What kind of cell culture irritation testing is performed?
MatTek Epiderm model
Measures redness of the skin
Transepidermal water loss
True/False: Irritation causes TEWL to decrease.
Method used to determine how much drug is in hair follicles
Differential tape stripping