SUNBURNS

what causes tanning?

UV (stimulates melanocytes) and produces melanin

what are the two tanning processes?

immediate pigment darkening and delayed tanning

what causes sunburn?

inflammatory response and vasodilatoin so redness and swelling

what are mild sunburn symptoms?

swelling, redness, and tenderness

what are severe sunburn symptoms?

blisters, fever, and chills

what are characteristics of UVC?

200-290 nm, blocked by the ozone, and not relevant for sunburn

what are characteristics of UVB?

290-320 nm, causes 90% of sunburn, causes skin cancer, and is needed for vitamin D

what are characteristics of UV A?

320-400 nm, penetrates deeper, causes photoaging, and found in tanning beds

what are features of phototoxicity?

first exposure, dose dependent, looks like severe sunburn, not immune

what are photoallergy key features?

immune mediated, requires prior exposure, not dose dependent, rash, blisters

are there drugs that cause photosensitvity?

yes there are

what is the peak sun exposure time?

10 am to 3 pm

when wearing wet clothing how much UV protection does it give?

allows 50% of the UV through

what is the mechanism of chemical sunscreens?

absorb UV radiatoin mostly UVB some UVA

why combine chemical sunscreen ingredients?

it increases SPF and broader UV coverage

what is a major side effect of PABA in sunscreen?

allergic reaction

is PABA short acting or long?

long acting

what UV protection do benzophenones provide?

UVA and UVB protection

what is an ingredient we look for in chemical sunscreens?

benzophenone

what is a risk of using benzophenones?

allergic reaction

what UV protection does cinnamates provide?

UVA and UVB

what is a downfall of cinnamates?

it doesnt adhere well to the skin

what UV protectoin does avobenzone provide?

UVA protection

are salicylates considered good sunscreens?

no they are weak sunscreens

what is a key ppint for anthranilates?

they are weak so they are used in combinatoin

what are adverse effects of chemical sunscreens?

contact dermatitis, photosensitivity, stinging, and sensitivity reactions

what is the mechanism of physical sunscreens?

reflect/scatter UV

what are the ingredients in physical sunscreens?

zinc oxide and titanium dioxide

what determines the effectiveness of physical sunscreens?

the thickness that they are applied

what are characterisitics of a physical sunscreen?

thick, visible on skin, and applied to targeted areas

if we want protection in a targeted area what type of sunscreen do we apply?

physical sunscreen

what are adverse effects of physical sunscreens?

white film, can stain clothes, must apply thick layer

when should sunscreen be applied?

15 minutes before sun

how much sunscreen should be used?

1 ounce full body

how often should sunscreen be reapplied?

every 2 hours

when should sunscreen be reapplied sooner?

after sweating or water exposure

how long do water resistant sunscreens protect you from water?

protect for 40 to 80 minutes in water

what does SPF measure?

UVB protection only

how much UVB protection does SPF 15 give?

93%

how much UVB protection does SPF 30 give?

97%

how much UVB protection does SPF 50 give?

98%

what is the recommended SPF level per the ADA?

SPF greater than or equal to 30

what does a SPF less than 15 mean?

sunburn prevention only

what is a broad specturm sunscreen?

protects against UVA and UVB and has SPF greater than or equal to 15

can sunscreen be used in infants less than 6 months?

no they must use shade and clothing

which sunscreen is best for children 6 months and up?

use zinc oxide or titanium dioxide