A patient with photosensitivity needs to take special precautions to reduce exposure to sunlight, especially in the ultraviolet (UV) spectrum.
Patients may have:
(1) a disease with decreased protection from actinic damage (oculocutaneous albinism, others)
(2) a phototoxic drug drug reaction
(3) a disease with photosensitivity (porphyria, systemic lupus erythematosus, etc.)
General protection:
(1) long sleeve shirts and pants
(2) hat with a broad brim
(3) socks
(4) sunscreen with SPF > 30, with very sensitive individuals requiring SPF >= 50
(5) dark glasses with UV block if photophobia present
(6) avoid direct sunlight, sitting in shade or under an umbrella
Factor |
UV Light Exposure Risk |
time of day |
maximal UV exposure from 10:00 to 14:00 standard time (11:00 to 15:00 daylight savings time = mid-day sun) |
time of year |
around summer solstice, may underestimate risk in the late spring |
cloud cover |
bright day without any cloud cover; UV exposure may be significant with light or partial cloud covers |
latitude |
increases as one goes nearer to the equator |
altitude |
increases with increasing altitude |
sand |
reflects UV light, especially when wet; may reflect light to someone sitting under an umbrella |
snow |
reflects light, especially on skin surfaces normally protected by hats or clothing |
water |
most UV light penetrates water; surface reflects light |
clothing |
wet clothing or clothing with loose weave |
windows |
penetrates nonreflective glass; blinds or curtains that only partially block light; reflective surfaces can diffuse light into the room |
Specialty: Dermatology