Shared Flashcard Set

Details

semi solids
d
22
Aerospace Engineering
Undergraduate 2
02/26/2012

Additional Aerospace Engineering Flashcards

 


 

Cards

Term
topical preparations
Definition
-localized effect
-drug penetrates into skin or mucous
-skin is target organ
-little systemic effect
-concerns only during pregnancy
Term
transdermal preparations
Definition
-drug penetrates through skin
-systemic delivery
-skin is NOT the target but rather a barrier
Term
creams
Definition
-thick emulsions
-o/w or w/o
-used topically, rectally, vaginally
-patient preference: spread and washability. w/o emul over an ointment
Term
ointments
Definition
-greasy
-used externally for skin or mucous membranes
-5 types
Term
hydrocarbon/oleaginous bases
Definition
-emollient effect, prevent loss of moisture, hard to wash off, used in occlusive dressings
-incorporation of only small amounts of aqueous media
-ex. petrolatum, yellow/white ointment
Term
absorption bases
Definition
-permits aq media to be absorbed forming w/o emulsions
-used as emollients
-oleaginous, not easily water washable
-useful for adding small amount of aq media into a hydrocarbon base
-ex. hydrophilic petrolatum, aquaphor, lanolin
Term
w/o emulsion bases
Definition
-permits incorporation of additional amount of aqueous media
-used as emollients
-oleaginous, not easily water washable
-ex. cold cream, eucerin, nivea
Term
o/w emulsion bases
Definition
-resembles creams
-contain emulsifying agents
-easily spreadable, washable, can add aq media
-"water-washable bases"
-ex. hydophilic ointment, dermabase
Term
water-soluble bases
Definition
-no oleaginous components
-water-washable
-don't incorporate large amounts of aq media, it will soften
-incorporates solid substances
-ex. polyethylene glycol ointment, polybase
Term
desired characteristics of appropriate base
Definition
-occlusion of moisture from skin
-stability and release rate of drug from base
-topical or percutaneous absorption
-drug on base consistency
-desire for water-washability
Term
levigating agents
Definition
-used to disperse solid before incorporations
-oleaginous bases, use mineral or cottonseed oil
-for aq bases, use glycerin, proylene glycol or PEG 400
Term
incorporation of a liquid
Definition
-use appropriate base if it can accept liquid and quantity
-pile ointment and make a hole in center to place liquid
-may use small amt of hydrophilic base to incorporate liq, then add to hydrophobic base
-may add co-solvent or levigating agent
Term
prep of ointments: fusion
Definition
-components are melted, combined and stirred until congealed
-heat labile components added to cooling phase
-prepared in beaker or dish or stem-jacketed kettle
-once congealed, pass through ointment mill, ointment tile w spatula or mortar and pestle
Term
pastes
Definition
-semi solids that contain more solid material than ointments
-stiffer, higher drug content
-no levigating agent
-stay in place better, absorbs secretions
-ex zinc oxide paste, toothpaste
Term
plasters
Definition
-solids or semisolids adhesive masses applied usually to skin
-provides prolonged contact at site
-ex salicylic acid plaster for corns
Term
gels
Definition
-semisolid systems consisting of dispersions of small or large molecules in an aqueous liquid vehicle
-particles form interlacing network
-small proportions needed (1-5%)
-are often clear if all additives are soluble in dispersion medium
Term
mechanisms for gelling agents
Definition
-macromolecule entaglement
-attraction b/w particles
-cross linking of macromolecules
Term
single-phase gels (gelling agent)
Definition
-soluble macromolecules distributed uniformly throughout media
-colloidal dispersion
Term
two phase gels (magma) (gelling agent)
Definition
-gel mass consists of floccules or distinct particles
-comprised of water insoluble particles that hydrate
-ex. M.O.M., Al hydroxide gel, bentonite magma
Term
hydrogels (gelling agent)
Definition
-water as dispersion medium
-highly absorbant
Term
organogels (gelling agent)
Definition
organic solvent or oils as dispersion medium
Term
soluble macromolecules (one-phase) (gelling agents)
Definition
-natural polymers (tragacanth and natural gums)
-semi-synthetic cellulose derivatives (methylcellulose, carboxymethylcellulose)
-synthetic polymers: high MW and water soluble polymer (poloxamers, carbomers)
Supporting users have an ad free experience!