Wangu(SI 4) is an acupoint of small intestine meridian of Hand-Taiyang, it has the same effect of Huangqin (baikal skullcap root), in many skin diseases, Wangu(SI 4) can relieve itching, Wangu(SI 4) or Huangqin (baikal skullcap root)can clear heat and dry inner dampness. So Wangu(SI 4) is a relieving itching point. 

外关Waiguan（SJ 5）is 柴胡 Chaihu(Bupleurum). 柴胡 Chaihu(Bupleurum) can relieve superficial evil, and skin diseases are superficial syndrome. 

So we can select Wangu(SI 4) and Waiguan（SJ 5）to relieve itching, such as eczema, urticaria, atopic dermatitis and psoriasis, etc..