Dosage Form

Start Studying!

Terms

undefined, object

copy deck

Define Solution: Liquid preperations that contain one or more soluble substances dissolved in a suitable solvent or mixture of miscible solvents
Define Syrup: Concentrated aqueous solutions that contain sugar or sugar substites
Define Elixer: Clear, sweetened, hydroalcoholic solutions for oral use
Define Spirit: alcoholic solutions of aromatic or volatile materials
Define Fluid Extracts: liquid preparations of vegetable drugs containing alcohol as a solvent. High alcohol content and more potent than tinctures
Define Aromatic Waters: Saturated aqueous solutions of aromatic or volatile materials.
Define Tinctures: Alcoholic or hydroalcoholic solutions prepared from vegetable materials or chemical substances
Define Suspensions: Multi-phase systems that contain finely divided particles distributed somewhat uniformly throughout a vehicle
Define Emulsions: A dispersion in which the dispersed phase is composed of small globules of liquid distributed throughout a vehicle in which it is immiscible
Define Microemulsions: Consist of large or "swollen" micelles containing the interal phase.
Define Gels: semisolid systems consisting of dispersions of small or large molecules in an aqueous vehicle rendered jelly like through the addition of a gelling agent
Define Magmas: Suspensions of inorganic acids such as clays in water, leads to a gel like consistency
Define Milks: Suspensions in aqeuous vehicles intended for oral administration
What are the three allowed methods of preparing Purified Water, USP: Distillation, Ion exchange, reverse osmosis
What are five other vehicles of oral liquid dosage forms (excluding purified water): Ethanol alcohol (solvent)
Glycerin (preservative)
Propylene Glycol (substitute for glycerin)
Sorbitol (preservative, laxative)
Edible Oils (solvent, laxative)
Why do vehicles that act as an osmotic laxative pose a problem?: Not a function you may want the vehicle to perform
Liquid Dosage Forms Advantages 4 & Disadvantages 5: Advantages
Flexibility
Ease of Administration
Fast absoption in GIT
Homogenous

Disadvantages
bulky
taste
stability of drug
solubility of certain drugs
accuracy of dose
Why may preservatives be neccesary in sryups and at what conc are they self preserving.: Low concentrations of sucrose may enhance microbial growth. 65% sucrose acts as a preservative
How much alcohol must be present in a sryup for it to be a preservative: 15-20%
When cant heat be used when preparing sryups: Heat cant be used if the ingrediant is thermolabile or volatile
(3) Disadvantages of Elixers: Alcohol
If patient is taking Antibuse
Causes drowsiness
What is the difference between Laudanum and Paregoric?: Laudanum = opium tincture (1g/100ml morphine)
Paragoric = camphorated opium tincture (40mg /100mL morphine)
What is extraction by maceration?: A communitued drug is extracted of its soluble constituted by SOAKING it in a suitable solvent until cellular structure is softened.
What is a Newtonian system?: material with flow properties that can be explained by Newtons law of flow
What is a non-Newtonian system: materials with flow properties that cannot be explained by Newtons Law of flow
What are three examples of non-Newtonian systems. And what kind of liquid dosage form belongs to each: Plastic Systems (concentrated focculated suspensions)
Pseudo plastic systems (emulsions)
Dilatant Systems (cibcebtrated defloculated suspensions, Zinc oxide paste)
Why do flocculated particles in concentrated suspensions exhibit plastic flow?: These particles do not flor until a certain minimum shearing strees is achieved
Why do polymers in solution exhibit pseudoplastic flow: Shear stress decreases viscosity, as you shake harder the liquid will become less viscous
How does processing of dilatant materials lead to equiptment damage?: The viscosity of the liquid increases with increaseing shear stress, the more you stir the more viscous it becomes
Define Thixotrophy: a phenomena explaining that when at rest, the liquid has high viscosity, when shearing stress is applied to the material and then removed, the material will have a relatively higher flowability
Why is wetting of solids a potential problem?: Dissolution problems, wont be absorb by GIT, too much will protect drug from GIT
What is the contact angle of a completely wetted powder: contact angle = 0 degrees
Define particle aggregation: small particles are attracted to each other to form larger heavier particles that tend to fall out of suspension
How can particle aggregation be prevented? (4 ways): By development of a surface charge. (Ionization of surface groups, preferential adsorption of electrolytes, adsorption of charged surfactant molecues from the solution, addition of flocculating agents)
Define interfacial tension: Tension between two immiscible liquids. Each liquid prefers to stay with the other molecules of that liquid.
Anionic surfactants: hydrophillic portion contains a negative charge, oral toxicity
Cationic surfactants: cation itself provided the emulsifying properties
Amphoteric Surfactant: hydrophillic portion possesses both positive and negative charges
Nonionic surfactants: hydrophilic portion possesses no charge
Naturally occuring compounds (surfactants): derived from plant and animal sources, short shelf life
What are two examples of naturally occuring surfactants and describe why they are needed in the body: Bile salts (digest fats)
Phospholipds (found in alveolar lining, film over cornea)
Common pharmaceutical uses of surfactants (4): Wetting
solubilization
Emulsification
Antibacterial action
Tweens form what kind of emulsion: o/w
Span form what kind of emulsion: w/o
List good qualities of suspensions 3: 1 Suspension shoud pour readily and evenly
2 Particle size should be small and constant
3 particles should settle slowly and easily be redispered when shaken
What is the name of the equation that governs sedimentation velocity: Stokes Law
How does a structured vehicle slow down sedimentation of a suspension: Avoids formation of cake
HOw does controlled flocculation improve suspension properties: Promotes a degree of interaction between suspended particles that will keep their surfaces apart
What are three things that can improve controlled flocculation: electrolytes, polymers/clays, surfactants
What are the factors that affect the rheology of an emulsion 4: 1 viscosity of continous phase
2 phase-volume ratie
3 emulsifier
4 droplet size and size distribution
What are the different types of emusifying agents 3: 1 Surfactants
2 Hydrophilic colloids
3 Finely divided solid particles
How does the emusifying agent surfactant work: It is adsorbed at the oil-water interface to form monomolecular films and reduce interfacial tension
How does the emusifying agent Hydrophilic colloids work: the form multi-moleculat film around the dispersed droplets of oil in an o/w emulsion
How does the emusifying agent Finely divided solid particles work: adsorbed at the interface between the two immiscible liquid phases and form a film of particles around the dispersed globules
What is the dry gum method of emulsion preperation: 1 acacia is first dispersed throughout the oil
2 water is added all at once
3 trituration is done at high speed until a snapping sound heard
4 remainder of aqeuous phase added
What is the wet gum method of emulsion preperation: 1 acacia diserped through 2 parts of water
2 oil added slowely
3 trituarted at high speed and remainder of water added slowly
(slow, less reliable than dry gum)
Calcium Soap emulsion (ingrediants & emulsion type): w/o
vegetable oil, Ca(OH)2
Soft soap emulsion (ingrediants & emulsion type): o/w
salts of fatty acids and a postive ion
What kinds of oils may be emulsified by Forbes method (2). Why cant other oils be used by Forbes method?: volatile oils
oils with low viscosities

Viscous oils cant be used because they cannot be thouroughly agitated in the bottle and mixed with the emulsifying agent
Creaming (Emulsion instability): seperation of an emulsion into two regions
Coalescene/Cracking/Breaking (Emulsion instability): ireeversible, filrm of the emulsifying agent surronding the droplets of the oil is broken
Phase inversion (emuslion instability): protection of emulsions against extremem temps
Define Liniments: Alcoholic or oleaginous solutions or emulsions of various medicinal substances intended for external applications to the skin with rubbing
Define Collodions: liquid preperations composed of pyroxylin dissolved in a solvent mixture composed of alchol and ether with or without added medicinal substances
Define Ointment: semisolid preperations intended for external applixation to skin or mucous membrances
Define Creams: viscous liquid or semisolid emulsions for topical application
Define Pastes: semisolid preperations containing atleast 20% solid
Define Plasters: solid or semisolid adhesive masses spred upon a backing material of paper, fabirc, moleskin or plastic
Define Glycerogelatins: plastic masses containing gelatin, glycerin, water and an aded medicinal substance
Define Rubifacients: agent that causes reddening and warming of the skin (KY WARMING GEL!!)
Define Counterirritants: agent that causes irritation when applied to the skin and is used inorder to relieve more deep-seated pain or discomfort
Define Emollients: soothes and softens the skin
Define Protectives: protects injured or exposed skin surgaces from harmful or annoying stimuli
Define Humectants: decrease the evaporation rate of water from the preperation, especially just after its applied to the skin
Define Antioxidents: delay the rancidfication of selected bases
What is the difference between a topical and a transdermal dermatological product: Transermal:skin is not target organ
Topical: skin is target organ
Why should liniments not be applied to bruised skin?: Excessive irriation might result
What is the function of camphor and castor oil in collodion formulations: Castor oil: makes product flexible for ease of use
Camphor: makes the product waterproof
What is the correct semisolid product to apply to moist, weeping, lesions and why: creams, because they have a drying effect in fluids that are miscible with their aqeuous external phase
Why do carbopols gel?: WHen a base is added the COOH group becomes ionized and aquires a negative charge, the molecule uncoils and increases the viscosity of teh gel (polymer now takes up more room)
Oleaginous/hydrocarbon ointment base: emollient effect, protect agaist escape of moisture, effective occlusive dressings, (Vasoline)
Absorption ointment base (two types): anhydrous: doesnt initally contain water, w/o emulsion
w/o emulsion: already contains some water, can add more water, cold cream
water removable ointment base: o/w emulsion, easily washed off, able to absorb serous discharges, may be diluted with aqeuous soltions
water soluble oinment base: cannot effectively add large amount of water, they become to soft, does not contain oleaginous components
What ointment bases allow for inforporation of aqueous material: Absorption (anhydrous, w/o), water removable bases
In what situations are levigating agents unneccesary? 4: 1. small particle size
2 quantity of solid is small
3 ointment base is soft
4 final product is to be a stiff ointment or paste
Levigating agent mineral oil is compatiable with what 3 bases: hydrocarbon/oleaginous base
absorption or emulsifiable base
w/o emulsion base
levigating agent PEG 400, glycerin, propylent glycol is compatiable with what 2 bases: o/w
water soluble bases
What levigating agent would be used to incorporate coal tar?: Tween 80
What levigating agent would be used to incorporate ichthammol?: glycerin, fixed oils, or aquaphor
what levigating agent would be used to incorporate peruvian balsam: castor oil
what method would be used to incorporate camphor, urea, testosterone into an ointment base: dissolution
Define fusion method and explain when it is primarly used: components mixed together by melting and cooled with constant stirring until a uniform preparation has been obtained. Used with heat sensitive and volatle ingrediants
How are eutectics incorporated into an ointment base: ingrediants triturated to for mixture and incorported into a base. levigation may be needed
Advantages of ointment tubes 4: lightweight
inexpensive
conventient
compatible with most formulative components
Why are pseudomonas aeroginose and staph aureous of particular concern with topical preperations: they have a high capacity to infect skin, espeicially in already compromised patients being treated for skin conditions

Start Studying!

Deck Info

Number of cards 96