Ointments & Veterinary Compounding Flashcards
When is compounding needed for animals:
- administration issues (dosage forms inappropriate, taste issues, mixing multiple meds = easier admin)
- customize dosages
- avoid toxicities from excipients in commercially available products
Animal Medicinal Drug Use Clarification Act (AMDUCA 1996)
prohibited drug use in food producing animals that would result in drug residues in the human food chain
banned use of : chloramphenicol, diethylstilbesterol, fluoroquinolones in food producing animals –> all can be toxic to humans consuming these animals
always consider the _____ of the animal
use!
- companion
- performance/working
- food-producing
ointments
semi-solid preparation for EXTERNAL application to skin/mucous membranes
(paste, gel, plasters)
ointment uses: (3)
- protect skin/mucous membrane
- provide skin hydration (emollient)
- vehicle for medication (local effect or systemic effect)
How to choose the ointment BASE (3)
consider:
- the use of the ointment
- properties of the incorporated medication (water soluble? not?)
- area of application
levigation
reduces particle size by triturating in a mortar with a small amount of liquid solvent (in which the solid is NOT soluble)
levigating agents
make it easier to incorporate solids into semisolid ointment bases –> resulting in smooth preparations
levigating agents are NOT required when
solid being incorporated is composed of very FINE particles, SMALL in quantity, ointment base is SOFT, or if ointment intended to be STIFF paste
solid powder must be ______ in levigating agent
insoluble
How to choose a levigating agent:
- chemically similar to ointment base
- always use minimal amount
dissolution
dissolve solid ingredient into solvent before incorporation into ointment base
solid powder must be ____ in dissolution solvent
soluble
when to use dissolution for powders
when solid is hard to incorporate
How to incorporate liquid into ointment
place base on ointment slab —> create depression –> pour liquid into depression –> spatulate small portions of liquid into base
1 oz = ___ g
1 oz = 28.35 g
BUD for ointments
180 days (6 months)
ointment counseling points
- external use only
- keep out of reach of children
Ideal properties of ointments (7)
- spreads easily
- compatible with topical administration
- stable
- smooth/pliable
- softens/melts at body temperature
- readily releases medication
- easily removed, doesn’t stain skin/clothing
drug release and penetration in to the skin from an ointment is a function of … (5)
- amount of pressure
- surface area covered
- condition of the skin
- base used
- use of occlusive dressing
for ointments containing 3 or more ingredients….
add ingredients sequentially to base —- do not mix ingredients together 1st if you have 3 or more — instead add each ingredient to base one at a time
5 types of ointment bases
- hydrocarbon/oleaginous
- anhydrous
- water-in-oil emulsions
- oil-in-water emulsions
- water soluble
Hydrocarbon/Oleaginous bases:
- examples
- drug release potential
- uses
ex. white petrolatum
poor drug release
uses: protectants, emolliants, vehicles for hydrolyzable drugs
Anhydrous bases:
- examples
- drug release potential
- uses
ex. aquaphor, aquabase, polysorb
poor drug release (better than hydrocarbon/oleaginous)
uses: protectants, emollients, vehicles for aqueous solutions/solids/non-hydrolyzable drugs
water/oil emulsion bases:
- examples
- drug release potential
- uses
ex. eucerin
fair to good drug release
uses: emollients, cleansing creams, vehicles for solid/liquid/non-hydrolyzable drugs
oil/water emulsion bases:
- examples
- drug release potential
- uses
ex. dermabase, unibase
fair to good drug release
uses: emollients, vehicles for solid/liquid/non-hydrolyzable drugs
water-soluble bases:
- examples
- drug release potential
- uses
ex. PEG ointment, Polybase
good drug release
uses: drug vehicles
Anhydrous vs. Hydrous bases
anhydrous - not as washable, spread less
hydrous - better drug release / less protective effect
levigation vs. dissolution
levigation
- levigate powder in minimal amount of base or mineral oil (NOT soluble)
dissolution
- dissolve powder in minimal amount of dH2O –> then incorporate in minimal amount of absorption base –> then incorporate into ointment base
