<prompt> A male patient presents with patchy loss of hair on scalp, eyebrows and beard. He also gives history of rapid graying of hair in a few areas. The likely diagnosis isAlopecia areataAnagen effluviumTelogen effluviumAndrogenic alopecia  <response>: Information provided in this question are -Patchy hair loss focal alopeciaHair loss on scalp, eyebrows and beardHistor of rapid graying of hairAll suggest the diagnosis of Alopecia areata -In Alopecia areata, hair loss is patchy and well circumcirbed.Alopecia areata most commonly involves scalp but any hair bearing skin e.g., beard, eyebrows, and eye lashes can be involved.The characteristic feature of alopecia areata is sparing of greywhite non-pigmented hair and preferential involvement of blockbrown pigmented hair. If alopecia progress rapidly, it appears as rapid greying of hair as black hair are shed and grey hair are spared Going graywhite overnight phenomenon. 