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


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


increases as one goes nearer to the equator


increases with increasing altitude


reflects UV light, especially when wet; may reflect light to someone sitting under an umbrella


reflects light, especially on skin surfaces normally protected by hats or clothing


most UV light penetrates water; surface reflects light


wet clothing or clothing with loose weave


penetrates nonreflective glass; blinds or curtains that only partially block light; reflective surfaces can diffuse light into the room


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