Brainscape's Knowledge GenomeTM

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


See full index

Dosage II > 21: Topical Transdermal > Flashcards

21: Topical Transdermal Flashcards

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

physiology of skin

A

-stratum corneum
-living epidermis
-dermis
-hair follicles and sweat glands

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

Stratum corneum

A

-main barrier to permeation
-brick (dead cells) and mortar (lipid) model
-permeation occurs by partitioning thru lipid material between dead cells
-lipid barrier
-state of hydration related to ease of permeation

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

Living epidermis

A

-living cells w/o capillaries
-get nutrition by diffusion from dermis
-source of skin color and tanning

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

Dermis

A

-contains capillaries
-drug needs to reach capillaries to achieve systemic action
-contains pain, thermal, tactile sensors
-injury must reach dermis to produce scarring

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

Hair follicles and sweat glands

A

-secondary route of drug absorption that bypasses the stratum corneum

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

Functions of the skin

A

-containment
-microbial barrier
-chemical/radiation/electrical/thermal barrier

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

skin pH

A

-5
-inhibits bacterial growth
-sebum has bacterio/fungostatic fatty acids

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

Skin as chemical barrier

A

-permeabiilty resistant

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

skin as a radiation barrier

A

-exposure to UV stimulates melanin which absorbed UV rays

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

skin as electrical barrier

A

-high impedance to flow of electrical current
-need to treat skin w salt solutions and overcome impedance to measure body potentials

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

Body temp

A

-98.6 by dilating/contracting blood vessels or sweating

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

Topical drug delivery

A

-local effects on barrier function (surface and stratum corneum effects)
-drug action on the skin’s glands
-effects in deep tissues

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

Transdermal drug delivery

A

-systemic drug delivery

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

Surface effects of topical drug delivery

A

-Zn oxide paste for diaper rash
-sunblock
-lip balms
-calamine, antibxs, deodorants, soaps

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

Stratum corneum effects

A

-emolliency: softening horny tissue
-keratolysis: chemical digestion and removal of horny tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

drug action on skin glands

A

-antiperspirants
-acne
-hair removers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

antiperspirants

A

-Al-Cl-
-irritate and close orifice of eccrine glands to impede sweat flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

acne meds

A

-soap, alc, antibxs
-retinoids reset the process of epidermal proliferation and differentiation = prevents formation of lesions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Topical drug effects in deep tissues

A

-topical steroids
-NSAIDs
-locak anesthetics
-lighten skin
-skin cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Topical Drug Delivery Platforms

A

-ointments
-pastes
-creams
-gels
-rigid foams

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Ointment bases

A

-hydrocarbon (more hydrophobic)
-silicone
-absorption
-water soluble (less hydrophobic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Hydrocarbon bases

A

-petrolatum
-polyethylene dissolved in mineral oil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

silicone bases

A

contain ppolydimethylsiloxane oil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

absorption bases

A

-ointment containing w/o emulsifiers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Water soluble bases

A

-polyethylese glycol ointment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Pastes

A

-ointments w high concentration of insoluble solids are added

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Creams

A

-o/w or w/o emulsion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Gels

A

-liquid phase trapped in matrix of polymer

30
Q

Rigid foams

A

-air or gad emulsified in a liquid phase
-liquid phase may contain drug
-aerosol shaving creams, medicated quick-breaking antiseptic foams

31
Q

Transdermal drug delivery

A

-some drugs can penetrate skin and enter systemic circulation
-good for drugs that experience high first pass metabolism

32
Q

Transdermal drug delivery structure

A

-backing membrane
–drug reservoir w drug molecules
-rate-controlling porous membrane
-skin-contact adhesive
-blood capillary

33
Q

Transdermal drug delivery permeability

A

-general inpenetrable
-permeability correlates w drug’s MW and Ko/w
-useful for drugs with high skin permeability and low dose requirement

34
Q

Permeability equation

A

log P ~ -2.7 + 0.71*logKo/w - 0.0061M
-P= permeability coefficient
-M= molecular weight
-Ko/w= oil/water partition coefficient

35
Q

Types of transdermal patches

A

-membrane-modulated
-adhesive dispersion
-matrix dispersion

36
Q

Membrane-modulated transdermal patches

A

-backiing membrane
-drug reservoir
-rate-controlling micropourous membrane
-adhesive

37
Q

Adhesive dispersion transdermal patches

A

-backing membrane
-drug reservoir
-rate-controlling adhesive

38
Q

Matrix dispersion

A

-backing membrane
-drug + adhesive

39
Q

slide 15

A

slide 15

40
Q

Transdermal nitroglycerin

A

-half-life: 3 min
-slightly soluble in water
-soluble in common organic solvents

41
Q

Transdermal nitroglycerin use

A

-prevent angina due to coronary heart disease
-not for immediate relief of acute attacks

42
Q

Transdermal rivastigmine use

A

-indicated for dementia associated w alzheimer’s or parkinsons

43
Q

transdermal rivastigmine dose

A

-4.6, 9.5, 13.3 mg/day

44
Q

Transdermal rivastigmine

A

-soluble in water, ethanol, acetonitrile, n-octanol, ethyl acetate
-log P: 2.3
-water solubility 2.04mg/mL
-backing film, drug matrix, adhesive matrix, release liner

45
Q

Transdermal contraceptive

A

-35mcg ee
-150mcg
-once a week for 3 weeks
-upper arm, abdomen, buttock, back

46
Q

Matrix-type transdermal system strucutre of xulane

A

-backing polymer layer
-middle layer: adhesive + matrix + active ingredients
-third layer: release liner

47
Q

Drug diffusion through skin

A

-across cellular-intercellular regions
-across lipid intercellular spaces
-across thin lipid layers sandwiched between flattened protein cells

48
Q

Factors affecting permeability

A

-hydration
-solubility of drug in stratum corneum
-excipients (solvents, surfactants)
-pH affects ionization

49
Q

Methods of penetration enhancement

A

-iontophoresis
-electroporation
-ultrasound
-prodrugs
-chemical

50
Q

iontophoresis

A

-uses low voltage electrical current to drive changed drugs through the skin

51
Q

Electroporation`

A

-uses high voltage short to creat pores in skin

52
Q

ultrasound

A

-use low freq ultrasonic energy to disrupt the stratum corneum

53
Q

prodrugs

A

-make lipophilic

54
Q

Chemical penetration enhancers

A

-alcohol, DMSO, surfactants, acetone, ethyl acetate

55
Q

Enhancers

A

-ionic surfactants
-ascorbate, dithiothreitol
-azone
-DMSO

56
Q

ionic surfactants

A

-disorder the lipid layer of stratum corneum to swell and/or leach out some of the structural components, thus reducing the diffusional resistance

57
Q

Ascorbate, dithiothreitol

A

-reducing agents
-disrupt disulfide bonds of proteins in keratinized cells

58
Q

Azone

A

-nonpolar, oily liquid
-fluidize lipid lamella region of stratum corneum

59
Q

Dimethyl sulfoxide (DMSO)

A

-dipolar solvent
-enter aq region of stratum corneum
-interact w the lipid polar heads to expand hydrophillic region between polar heads

60
Q

slide26

A

slide26

61
Q

Types of microneedles

A

-dissolving microneedles
-hydrogel forming
-seperable
-hollow

62
Q

Dissolving microneedles

A

-type of polymeric MN that can degrade or dissolve postinsertion into the skin
-leads to delivery of excapsulated drug at site of application

63
Q

Hydrogel forming microneedles

A

-have cross-linked hydrogel structure that can collect interstitial fluid upon skin application to in-situ hydrogel

64
Q

Separable microneedles

A

-rapidly dissolvable backing layers
-weaker connections between backing layers and MN tips, or based on hydrogel backing layer

65
Q

Hollow microneedles

A

-each needle incorporates a hollow cavitiy within and a bore on the needle tips to which small volumes of drug can be injected

66
Q

PVP

A
67
Q

Patches application sites

A

-upper chest/back
-upper arm
-flanks

68
Q

Patch freq

A

-daily
-BID
-2 weekly
-weekly
-72h

69
Q

Common errors in transdermal patch administration

A

-prep
-removal
-application
-monitoring (displacement)
-storage and disposal

70
Q

Some patients do not realize

A

-patch must be applied directly to skin (do not tape)
-remove protective liner
-use one at a time
-where to place (rotate)
-when to change
-TSS
-do not cut patches for kids

Dosage II (20 decks)

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