Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

DDS > Topical DDS > Flashcards

Topical DDS Flashcards

1
Q

What does topical refer to?

A

Application of the drug locally
-mostly skin
-membranes
-mouth
-eye
-nasal

Topical DDS: Ointments, Cream, Gel, Pastes, Lotions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Difference between dermatological skin products and Transdermal drugs?

A

dermatological skin products mostly work topically on the skin (inflammation, psoriasis, actinic keratosis), Transdermal will go into the blood (systemically)

Analgesics often work on joint muscles, still considered topical (grey area - bc the blood may take it there)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the routes that deliver topical preparations?

A

-Dermatological: ALL - TOPICAL or SYSTEMIC
-Nasal (rich blood supply): Ointment, Gel - mostly topical, also systemic
-Rectal: Ointment, Gel, Cream -> perianal and anal canal
-Vaginal: Ointment, Gel, Cream, Foam

(Otics and Ophtalmics can also be considered topical bc there is no high Bioavailability on those routes)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Rectal indications:

A

Anorectal pruritus, inflammation, hemorrhoids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Vaginal indications:

A

Anti-infectives, hormones, pH modifiers, spermicides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Definition of Ointments or Ointment Bases

A

Ointment Bases: Mixture of Oil, water, and different excipients + DRUG

-Semisolid preparations for external use to the skin or mucous membranes
-melt at body temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Characteristics of od ideal Ointments

A

-Spread easily, Non-gritty (should be fine)

-semisolid plastic flow: often stiff -> shear and yield value need to be crossed for the ointment to spread, can also be pseudoplastic if the yield value doesn’t exist that much

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Types of Ointment Bases: USP Classification

OLEAGINOUS BASES

A

-Water insoluble and Not water washable
-Oily greasy, and Occlusive (Emollient) -> it forms a layer and prevents the water from evaporating from the skin (no dehydration)

-Lack of cosmetic appeal
-Applied on dry skin bc of emollient effect, Not applied on hairy areas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Examples of Oleaginous Bases

A

-Hydrocarbons: Mineral oils, petrolatums, paraffins, waxes
-oils: Castor oil, cottonseed oil, olive oil
-Synthetic esters and alcohols: Glyceryl monostearate, butyl stearate, isopropyl lanolate, cetyl alcohol, stearyl alcohol

-White petrolatum (refined Vaseline, used in LAB to make Zinc oxide paste)
!!-White ointment: A mixture of white wax and petrolatum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Types of Ointment Bases:

ABSORPTION BASES - Type A

A

Bases that can form w/o Emulsions

-Anhydrous, it has oily ingredients (petrolatum, waxes) and an emulsifying agent -> which can absorb excretes from wounds or edema

-Can absorb water (to create a w/o emulsion), but has NO WATER

-Water insoluble and Not water washable
-Oily, occlusive, and lacks cosmetic appeal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Examples of Absorption Bases

A

!!-Anhydrous Lanolin (woot fat)
-Hydrophilic petrolatum
-Aquaphor -> contains Petrolatum, Lanolin alcohol (EMULSIFIER)
Aquabase generic for Aquaphor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Types of Ointment Bases:

ABSORPTION BASES - Type B

A

Absorption Bases that are w/o Emulsions - it has oil, water, and an emulsifier -> also used for weeping wounds to absorb excretes

-Water insoluble and Not water washable
-Can absorb water and contains water
-Easy to spread and Cosmetically elegant
-Occlusive

Examples: !!Hydrous Lanolin, Nivea, Eucin (these products have water as excipient)

How can you contain water, and absorb water, but also be water insoluble?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Water removable Bases

called CREAM

A

-o/w emulsion (w/o also possible) often called a CREAM -> oil, emulsifier, and water as the external phase

-Easily washed from the skin, can absorb serous
discharges
-not as occlusive
-humectant: help moisturize by adding water (different to Emollient in w/o ointments)

Example: Hydrophilic ointment, USP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Watersoluble Bases

A

-Water soluble and water washable
-Can absorb water
-Anhydrous or hydrous
-no oil phase, easy to remove

Examples: Composed of polyethylene glycols (PEGs; Macrogols)
MW varies depending on the number of polymers (PEG 400 liquid - PEG 8000 solid, would be melted before use)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Criteria on how to choose the appropriate Base

A

*Release rate -> water-soluble drugs wouldn’t want to leave the base
*Topical or percutaneous drug absorption -> some drugs are absorbed better, hence go deeper f.e. Steroids have better absorption in oleaginous base than in creams
* Occlusion -> for dry skin
* Stability of drug -> if not stable in water don’t use o/w
* Effect of drug on ointment base -> drug and base shouldn’t be complexing or reacting in a way that it hinders the drug
* Easily removable?
* Characteristics of surface for application

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Applications to prepare Ointments:

A

-Ointment Slab/Pill Tile/Spatula
-Mortar/Pestle (not preferred bc of losses)
-Unguator
-Ointment Mill

17
Q

Compounding Ointment:

A

-When working with solids (like powder), the first step is to LEVEGATE (reduce particle size w/ liquid) with f.e. glycerin and SPATULATION

-Then add the semisolids (LAB example: Lanolin and petroleum by geometric dilution)

18
Q

Compounding Cream:

A

The oily phase may have solids that need to be melted -> start with the material with the highest melting point, then continue with solids with lower MP

-water phase has to be a few degrees higher
-W/O: add water slowly; O/W: add oil slowly
-Cooling with constant stirring -> promoteS the fusing of the oil and water phase and the formation of the cream

-HEAT: prevent evaporation of water, and be careful w/ heat-labile drugs and excipients (degradation)

19
Q

Selection of Levegation Agent:

A

-For W/O Emulsion bases, Oleaginous, Absorption: Mineral Oil

-For O/W Emulsion bases, water-soluble bases:
Glycerin/Propylene Glycol/Water

20
Q

Ointment Packaging and Storage

A

Jars: Glass, Plastic - Do not pour in while hot!
Disp. Jars: Plastic
Tubes: Plastic, tin, aluminum
Syringes: Individually dosed, good protection of the product

Store in a cool place and avoid the extreme temperature (no fridge)

21
Q

Definition of creams

A

semisolid preparations with medicinal agents
dissolved or dispersed in a W/O or an O/W emulsion (w/o are often creams)

Characteristics: Semisolid, Pseudoplastic flow (viscosity reduces as you apply shear), small force will initiate flow

For skin, rectal, and vaginal

22
Q

Difference between Ointments and creams:

A

Ointments: w/o

Creams: mostly o/w, Pseudoplastic flow, easier to spread and to remove

23
Q

Definition of Pastes

A

Thick, stiff ointments, don’t flow at room temperature -> protective coatings, so the skin doesn’t get any rashes

-Semisolid, plastic flow with definite yield value (harder to spread)

-Some may have dilatant flow (resistance to flow increased with the increased force of application)

24
Q

Definition of Lotions

A

-Aqueous preparations -> need insoluble material for external application without friction

-Newtonian and free-flowing (better flowing than creams), flows under gravity
-No yield value
-also refer to o/w and w/o emulsions

->preferred in surfaces that rub against each other with more friction

25
Q

Definition of Gels

A

-Semisolid systems consisting of dispersions of small or large molecules in an aqueous liquid vehicle
-jelly-like due to gelling agent
-A semi-rigid system -> dispersing medium (liquid) is restricted from moving by the network of particles

26
Q

Types of Gels:

A

Single Phase:
-Macromolecules are uniformly distributed - no
boundaries between the macromolecules and the liquid
-involves organics

Two Phase:
-consists of floccules and particles
-involve inorganics (like AlOH2)

Hydrogels: when the Gel has water as a vehicle
Polymers that like water and swell: Silica, bentonite, pectin, sodium alginate, methylcellulose, alumina

Organic Gels: if the drug is not water-soluble, a lipophilic base can be used: Contain an organic liquid (e.g. Plastibase)

27
Q

Different Gels:

A

-Carbomer Gels: Aqueous dispersion neutralized
with sodium hydroxide

-Methylcellulose Gels
-Starch Glycerite
-Aluminum Hydroxide Gel

28
Q

Mechanism of Gelation
Example with Gelatin

A

As gelatin cools, the gelatin macromolecules lose
kinetic energy ->

macromolecules associate through a dipole-dipole interaction into aggregates ->

chains increase so that the dispersing medium (water) gets trapped in the interstices (spaces) -> viscosity increases to that of a semisolid - GEL is formed

29
Q

Gelating agents

A

▪ Gelatin
▪ Agar
▪ Pectin
▪ Irish moss
▪ Tragacanth

30
Q

Phenomena in Gels

A

-Syneresis: Interaction between the dispersed phase (particles) and dispersed medium (liquid) is so great that the liquid is squeezed out the gel shrinks -> Gel is not stable

-Swelling: gel takes up liquid (humidity) and volume increases
-Imbibition: gel takes up liquid without measurably increasing its volume (but you can recognize it when weighing)

-Thixotropy: reversible sol-gel formation when applying to the skin is desired, no change in volume or temperature

31
Q

Application of Gels

A

-Oral, Intranasal, Topical, Vaginal, Rectal

32
Q

Quality control of Gels

A

▪ Appearance
▪ Uniformity
▪ Weight/Volume
▪ Viscosity (pseudoplastic)
▪ Clarity
▪ pH
▪ Other

33
Q

Stability of Gels

A

-Physical Stability: Shrinkage, separation of liquid from the gel, discoloration

  • Microbial Stability

-BUD: when in refrigerator: 14 days not preserved, 35 days if preserved

34
Q

Patient counseling for Gels:

A

-Proper application -> Probably “For External Use Only”
-Proper storage: Room or refrigerated temperatures
-Keep tightly closed prior to use

35
Q

Augmented Topicals

A

Augmented forms (topical corticosteroids) penetrate the skin more quickly and work faster due to propylene glycol (chemical enhancer) bc it can dissolve the lipid in the outer skin layer

-creams, ointments, lotions, or gels
-Example: betamethasone dipropionate 0.05%

36
Q

Product selection:

A

-Dry, scaly skin: Ointment

-Wheeping or oozing surface: topical powders,
Creams, gels - something that absorbs excretes (caution, some have alcohol)

-Intertriginous areas (two skin parts rub together) or
areas of friction: Lotion, gel

-Hairy areas: Gels (Hydrogels)

37
Q

Product selection:

A

-Steroids: More effective in a petrolatum base than
in a cream (o/w) vehicle

-Gels: Faster drug release than ointments and creams (bc the drug has to partition out of the ointment or cream)

-Container: Jars for large quantities,
tube provides better protection from contamination + more convenient

-Creams, Lotions: May break down if exposed
to excessive heat or sudden changes in temperature

-Lotions: Shake well before use

-Open wounds: Never apply over open
wounds unless it is labeled as a sterile product

38
Q

Further counceling

A

often ointments and creams contain glucocorticoids -> adverse reactions with systemic absorption

-minimal amounts (use the finger-tip unit (FTU) from a 5mm tube), no occlusive dressing -> to reduce the chance of increased absorption of glucocorticoids

-Avoid applying to wounds, and avoid strong steroids in sensitive areas (face, genitals) bc of increased absorption

DDS (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions