Topical preparations - ointments & creams Flashcards
define ointments
semisolid preparations intended for EXTERNAL application
true or false
ointments are liquid preparations
false - semisolids
name the types of ointments
-medicated ointments
-nonmedicated ointments
further classify medicated ointments
dermatological ointments
ophthalmic ointments
further classify non medicated ointments
-vehicles for medicated ointments
-used for emollient and lubricant effects
name all of the classes of ointment bases
-oleaginous bases
-absorption bases
-water-removable bases
-water-soluble bases
true or false
minimal grittiness feeling is okay when applying ointments
FALSE - no grittiness should be felt
oleaginous bases can also be known as…
hydrocarbon bases
true or false
hydrocarbon bases are water free preparations
true
what are hydrocarbon bases mainly used for?
emollient (moisturizing/soothing) effect (vaseline)
true or false
hydrocarbon bases do not tend to stay on the skin for long periods
false - they do
how do hydrocarbon bases have an emmolient effect?
they do not permit the escape of moisture from the skin
true or false
oleaginous bases are difficult to wash off
TRUE
give 5 examples of oleaginous bases *
petrolatum, usp (vaseline)
white petrolatum, usp
yellow ointment, usp (simple ointment)
white ointment, usp
mineral oil (liquid petrolatum)
simple ointment is also known as
Yellow Ointment, USP (oleaginous base)
yellow wax/petrolatum is also known as…
Yellow Ointment, USP/simple ointment
(oleaginous base)
what is liquid petrolatum
mineral oil (oleaginous base)
what is Vaseline
Petrolatum, USP (oleaginous base)
name the types of absorption bases and differentiate them
anhydrous absorption base and W/O emulsion base
anhydrous absorption bases contain NO WATER but can absorb added water to become W/O EMULSION BASE
_______ results in a W/O emulsion when it permits the incorporation of aqueous solution
anhydrous absorption bases
(hydrophilic bases)
give 6 examples of anhydrous absorption bases
hydrophilic petrolatum
anhydrous lanolin, USP
refined wool fat (lanolin)
modified lanolin, USP
aquabase
aquaphor
what is lanolin
wool fat
refined wool fat = anhydrous absorption base
hydrous wool fat = W/O emulsion (absorption base)
name the components of Hydrophilic Petrolatum, USP *
cholesterol, stearyl alcohol, white wax, and white petrolatum (a hydrocarbon base!)
true or false
W/O emulsion bases permit the incorporation of small, additional quantities of aqueous solutions
true
give 5 examples of W/O emulsion bases
-Rose Water Ointment, USP
-Hydrous Wool Fat (Lanolin, USP)
-Eucerin
-Cold Cream
-Hydrocream
true or false
W/O emulsions are absorption bases that do not have emulsifying agent
false - does have emulsifying agent
white petrolatum is what kind of base
oleaginous/hydrocarbon
aquaphor is what kind of base
anhydrous absorption base
hydrophilic ointment is what kind of base
oil in water emulsion (water removable)
eucerin is what kind of ointment base
water in oil emulsion base
which ointment base contains preservatives and why?
O/W (water removable) bc it contains a lot of free water
explain the use of water removable bases (O/W emulsion base)
they can absorb serous discharges in dermatological conditions
give examples of water removable bases
Hydrophilic Ointment, USP
give the components of Hydrophilic Ointment, USP and explain which components are oil soluble
Stearyl alcohol and white petrolatum (oleaginous base)- oil soluble
water soluble = propylene glycol, SLS (emulsifying agent), methylparaben propylparaben, water
true or false
water-removable bases contain an emulsifying agent
TRUE
SLS in the case of Hydrophilic Ointment, USP
explain the components of water soluble bases
contains ONLY WATER SOLUBLE COMPONENTS, but NO WATER
NO oleaginous material is included
give examples of water soluble bases
polyethylene glycol ointment
PEG 400 - 60% (LIQUID)
PEG 3350 - 40% (SOLID)
PEG of greater than what MW is solid?
greater than 1000 = solid
lower than 1000 = liquid
what is a potential issue for water removable bases?
it may be hard to maintain the viscosity of the base if too much water is added. absorption base is thus usually preferred
___g aquaphor: ___g water
1:1
what is carbowax
polyethylene glycol
–water soluble ointment base
want to find 1 PEG that is solid and 1 PEG that is liquid and mix them to give the desired consistency
carbowax is made through what method?
fusion method. highest MP melted first
what are 7 things to consider to select the appropriate ointment base?
-the desired release rate of the drug from the base
-if you want topical or percutaneous absorption
-if you want occlusion of moisture from the skin
-the stability of the drug in the base
-the effect of the drug on the consistency (or other features) of the base
-if you want a base that is easily removed by water
-the characteristics of the surface to which it’s applied
true or false
if a drug is hydrophobic, a hydrocarbon/oleaginous base should NOT be used
TRUE
the drug will dissolve and won’t get released from the base to have a therapeutic effect
for which ointment base is its occlusion properties the best?
hydrocarbon
true or false
if the drug interacts with the emulsifying agent in O/W base or W/O base, the ointment is not stable
TRUE
ointments usually have a ___ loading dose of drug
what does this mean?
low
don’t choose a drug that is soluble in the base bc there will be no release
define an ointment base
the semi solid vehicle into which drug substances may be incorporated in preparing medicated ointments
when preparing ointments, what is the limit on the %w/w drug?
10% or less
what is something to consider when determining the quantities needed to prepare an ointment base?
must consider how much will be lost during compounding
name come compounding equipment for ointments
-ointment slabs or ointment pads
-spatulas
which is preferred and why - ointment slabs or ointment pads?
slabs because they don’t move around as much
name the types of spatulas that can be used in the preparation of ointments.
how do you select which one to use?
metal
soft rubber
hard rubber
metal is usually preferred because it provides a strong force to mix an ointment (which is viscous)
when a drug such as IODINE is incompatible with metal, a hard rubber spatula is used
the soft rubber spatula can aid in transferring the product from the mortar
name a component of ointment that could be incompatible with a metal spatula
iodine
what is the ideal drug form to choose when preparing an ointment?
choose the powder form of the drug with very small size.
do NOT use the crystalline form because it will be very difficult to reduce the particle size. use amorphous form.
true or false
particle size of the drug is not very important in the preparation of ointments
FALSE - it is.
we cannot feel grittiness when applying the lotion
what is added in the preparation of lotions to ensure there is no grittiness felt when applying on the skin?
a levigating agent.
in what quantities should we use a levigating agent when preparing ointments?
the smallest amount possible.
the levigating agent is normally not included in the original prescription.
true or false
documentation is not necessary when including a small amount of levigating agent in the preparation of ointments
FALSE - it is necessary
if the levigating agent can’t sufficiently reduce the particle size in ointment preparation, what should you do?
for utech (idk how to spell it) mixture of camphor:menthol (crystalline) 1:1 ratio dissolved in alcohol and then removal of alcohol
this is PULVERIZATION BY INTERVENTION
name 3 levigating agents and when they can/can’t be used
mineral oil
glycerin
propylene glycol
mineral oil should be used for bases in which oil is the external phase and the drug is WATER SOLUBLE
glycerin should be used for bases in which WATER is the external phase, but the drug is OIL SOLUBLE (same with PPG)
define a levigating agent
a liquid used as an intervening agent to reduce the particle size of a drug powder by grinding together, usually in a mortar and using a pestle
true or false
a levigating agent is always needed in preparing an ointment to sufficiently reduce the particle size
FALSE
the first choice is to use the base itself to reduce the particle size and no levigating agent.
however we must use levigating agent to reduce the particle size if necessary
what are the methods of preparing ointments?
-incorporation method
-fusion method
-fusion/emulsification method
explain the incorporation method of preparing ointments
-the components of the ointments are mixed together by various means (WITHOUT the aid of heat)
small scale =
mortar and pestle (no - spatula preferred and ointment slab)
geometric dilution
levigation of solid
incorporation of liquid
filling of ointment jar
large scale=
in manufacturing -
mechanical ointment roller mills
true or false
a mortar and pestle is NOT the first choice in preparing ointments
true - spatula + ointment slab are preferred
why is geometric dilution so necessary in the incorporation method
to ensure homogeneity
explain the fusion method of preparing ointments
USES HEAT
all (or some) of the components are combined by being melted together and cooled with constant stirring until congealed (become semi solid upon cooling)
name some ingredients that when incorporated must use fusion method
beeswax
paraffin
stearyl alcohol
PEG (high MW)
true or false
glycerin and PEG should not be mixed together when preparing ointments
true
the PEG could melt
true or false
glycerin can be used in a hydrocarbon base
FALSE
can use water removable
true or false
when working with carbowax it must be prepared using fusion method
true - it is a solid
true or false
mineral oil cannot be used as a levigating agent with white petrolatum
FALSE -it can. oleaginous base. levigating agent and external phase should be miscible
explain the fusion/emulsification method of preparing ointments
an emulsion type ointment is prepared by a melting process and an emulsification process
oil and waxes are melted together in a steam bath 70-75 degrees celsius. an aqueous solution of the heat stable, water soluble components are heated also 70-75 degrees celsius
slowly, the aqueous solution is added to the melted oleaginous mixture with constant stirring
in the fusion/emulsification method of preparing ointments, is the aqueous phase added to the oil phase or vice versa? why?
aqueous solution is slowly added to the melted oleaginous mixture with constant stirring.
if oil is added to the water, it will separate right away
name 5 antimicrobial preservatives used in ointments
hydroxybenzoates
benzoic acid
benzalkonium chloride
phenol
sorbic acid
how is microbial content considered when preparing ointments?
have to consider the microbial content that is able to include an infection of the skin
they are not however required to be sterile (like eye products)
true or false
strict adherence to hygienic practices are required when preparing ointments
true
true or false
there are no regulations on the amount of ointment contained in the container
false - there is a minimum fill requirement
what are the packaging options for ointments?
-large mouth ointment jars
-metal or plastic tubes
are there any regulations on uniformity when preparing ointments?
yes
within lot and lot to lot standards
true or false
ophthalmic ointments must be sterile
true
true or false
ophthalmic ointments must be pyrogen free
false – just must be sterile and free from microorganisms
name an advantage of opthalmic ointments (over ophthalmic solutions) and a disadvantage
advantage - increased ocular contact time which means less frequent application
disadvantage - blurred vision bc tears won’t wash away the ointment
which is the #1 choice for ophthalmic products - solutions or ointments
solutions
explain the type of ointment base that is used in ophthalmic ointments
their melting or softening point should be close to the body temperature.
the typical ointment base is a hydrocarbon base - mix of petrolatum (vaseline) and liquid petrolatum (mineral oil)
the typical ointment base for ophthalmic ointments is a hydrocarbon base - mic of petrolatum (vaseline) and liquid petrolatum (mineral oil)
what is an advantage of this base?
it does not contain free water and thus does not need a preservative. the ointment can be multidose
what time of the day are ophthalmic ointments usually applied
at night and are diluted when you wake up
true or false
all ointments in the market are for use on the skin
FALSE
there are also ophthalmic ointments
define creams
viscous liquid or semisolid EMULSION of O/W or W/O type
what are creams used as?
emollients or as medicated applications to the skin
name 2 advantages of creams over ointments
they are easier to spread (viscosity not as high) and easier to remove
name 2 creams available in the market
vanishing cream and cold cream
explain what vanishing cream is
generally O/W emulsions that contain a large percentage of stearic acid and water
(contains emulsifying agent!)
explain what cold cream is
a semisolid, white W/O emulsion.
consists of:
-cetylesters wax
-white wax
-mineral oil
-sodium borate
-purified water
the sodium borate and free fatty acids in the wax forms a SODIUM SOAP. enhances skin moisturization. penetrates into the dry skin to bring the water in
true or false
both vanishing cream and cold cream contain an emuslifying agent
true
cold cream is W/O emulsion and vanishing cream is O/W emulsion
which is more greasy - vanishing cream or cold cream?
cold cream bc it is W/O emulsion
besides sodium borate + free fatty acids (cold cream), what else reacts to form a soap
olive oil + lime water in bottle/forbes method of preparing emulsions
which has higher viscosity - creams or ointments?
ointments
