PCOL of Sunscreens (Maize) Flashcards
Types of Ultraviolet Light (3)
UVB
UVA
UVC (antibacterial)
UVB:
- ___ to ___ nm
- Can cause _____, skin ________ and premature _____ of skin
- Produces vitamin __ in the skin
- 290 to 320
- sunburn, carcinoma, and aging
- D3
UVA:
- ___ to ___ nm
- Produces ______ and drug related ___________
- Able to ________ further into the dermis than ___ radiation
- No _____ because it is ___ to ____ times less energetic than UVB radiation
- 320 to 400
- tanning; photosensitivity
- penetrate, UVB
- erythema, 800 to 1000
Factors that affect tanning (7)
- time
- cloud
- reflection (snow, water, sand)
- location
- clothing
- the thickness of the epidermis and stratum corneum
- the pigmentation of the skin
Skin Type:
- Always burns easily, never tans
- Eyes are blue or green and hair is blond or red.
Skin Type I
Skin Type:
- Always burns easily, tans minimally
- Eyes are blue, hazel or brown, and hair is blond, red or brown.
Skin Type II
Skin Type:
- Sometimes burns and tans gradually
Skin Type III
Skin Type:
- Burns minimally, always tans well
Skin Type IV
Skin Type:
- Rarely burns, tans profusely -Brown skin
Skin Type V
Skin Type:
- Never burns, deeply pigmented -Black skin
Skin Type VI
UVA Tanning Mechanisms (2)
- Immediate pigmentation
- Delayed pigmentation
Immediate Pigmentation:
- Oxidizes the ______ already in the epidermis
- _____ darkening starts 5-10 minutes after exposure
- Lasts __-__ hrs
- melanin
- Pigment
- 24-48
Delayed Pigmentation:
- UVA stimulates the increase in the number of __________ and increased _______ in these cells
- Takes about __ to __ hours to develop after exposure
- Peaks at _ to __ days and lasts weeks to months
- melanocytes, pigment
- 48 to 72
- 7 to 10
UVB Tanning Mechanism:
- Stimulate epithelial cell _____ making skin ______
- Growth of the skin spreads _______ through more layers of the skin
- Protects the skin by ________ and __________ additional UV radiation
- ___ hyperpigmentation does not protect skin long term as much as ___ hyperpigmentation
- growth; thicker (causing wrinkles)
- Growth of the skin spreads melanin through more layers of the skin
- absorbing and scattering
- UVA; UVB
Sun Burn
- ___ penetrates into the dermis and causes an _______ reaction causing ________, ________, and __________ to be released.
- UVB; inflammatory; histamine, cytokines, and prostaglandins
Sun Burn Symptoms are (3)
mild erythema, tenderness, and edema
Severe Sun Burn Symptoms
- Second degree burn with blisters
- Fever, chills, weakness and shock (sun poisoning)
- The minimum single dose of UV radiation dose that produces clearly marginated erythema in the irradiated site.
- can be dependent on skin color, current medications, etc
Minimal Erythemal Dose (MED)
MED Type and characteristics
- MED 1:
- MED 2:
- MED 4:
- MED 8:
- 1 MED: pink
- 2 MED: bright erythema
- 4 MED: painful sunburn
- 8 MED: blistering burn
Definition of SPF:
- Sun Protection Factor
- MED of protected skin/MED of unprotected skin
- Personal time to get 1 MED
The higher the SPF:
- ____ likely to burn
- ______ time that can be spent in the sun
- Less
- Longer
- SPF __ blocks approximately __% of all incoming UVB rays.
- SPF __ blocks __%
- SPF __ blocks __%
- 15; 93%
- 30; 97%
- 50; 98%
SPF figure
Burning begins the minute you step into the sun
SPF: delays the burning process
Ex: pt who turns pink in 10mins uses a SPF of 4; now, it will take 40 before he turns pink
SPF over 30 is a waste
Proper SPF Selection:
- Start ____ and go ___; adding higher SPF after _ ___ will not help much
- Must apply correct amount at correct time
- Must re-apply every __-___ minutes
- high; low; 1 MED
- 90-120
SPF Selection per Skin Type:
- SPF>__ for Skin type I, II, increased risk of skin cancer
- SPF>__ for Lupus
- SPF>__ for photosensitizing drugs
- SPF __ to __ for Skin type III to V
- ____ ________ SPF needed for Skin type VI
- > 30
- > 40
- > 45
- 15 to 24
- Very minimal
Drugs that cause photosensitization (6):
Tetracycline Coal tar products Diuretics Estrogens and progestins NSAIDS Sulfonylureas
Ability to stay on the skin and remain effective
Substantivity
Substantivity can be related to 2 things:
vehicle
chemical
Substantivity:
- ______ have the worst substantivity
- _____ based vehicles have better substanitivity than alcohol based vehicles
- ____________ bases have good substantivity because they are not easily ________ ___
- ____ have the best substantivity, but are an ________ dosage forms
- Alcohols
- Cream
- Polyacrylamide; washed off
- Oils; unpleasing
Substantivity Selection: Choose a product that has the best substantivity. - Very water-resistant products: \_\_ mins - Water-resistant products: \_\_ mins - Sweat-resistant: \_\_ mins
- 80
- 40
- 30
Sunblocks (aka _________ ________)
MOA:
- _______ or ________ 100% of all UV radiation from 290 to 760 nm
Uses:
- Prominently ________ _____ like nose and ears
- Used when cannot _____ or _____ sun exposure
physical sunscreens
MOA:
- Reflects or scatters
Uses:
- exposed areas
- limit or control
Sunblocks and sunscreens are practically the same. (True/False)
False
Sunblock products
Zinc oxide, titanium dioxide, and red petrolatum
Sunblock Side effects:
- May occlude pores causing _____, ______, ____
- May stain clothing
Not easily removed with ____, but melts in hot sun
Protection decreases after _ ____ of direct sun contact
- miliaria, folliculitis, acne
water, but melts in hot sun
2 hours
Sunscreens (aka _________ sunscreens)
MOA:
- _____ UVB radiation
- ___ classes of sunscreens can absorb some UVB radiation
- All sunscreens are a _________ of products
- But only ________, _________, and ____________ can absorb UVA
chemica MOA: - Absorbs - All - combination - benzophenones, anthranilates and dibenzoylmethane
Chemical classes of Sunscreens (6)
- Para-aminobenzoic acid (PABA)
- Cinnamates
- Salicylates
- Benzophenones
- Anthranilates
- Dibenzoylmethane
Sunscreen chemical class - UVB
- The most effective at absorbing UVB rays
- May stain clothing
PABA
Sunscreen chemical class - UVB
- Do not adhere to skin well and depend on the vehicle for substantivity
Cinnamates
Sunscreen chemical class - UVB
- Does not adhere to the skin well
- Easy removed by water or perspiration
Salicylates
Sunscreen chemical class - UVA
- Poor substantivity
- Can cause sensitization
Benzophenones
Sunscreen chemical class - UVA
- Absorbs UVA radiation up to 370 nm
- Used only in combination products to give broad UV coverage
Anthranilates
Sunscreen chemical class - UVA
- Absorb mostly in the UVA range
- Activity decreases after 15 minutes of use
Dibenzoylmethane
Sunscreens ______ UVB radiation, sunblocks ______/________ UV radiation.
absorb, reflect/scatter
