Analysis of illness: Hello, Zuogui Pill is used for tonifying kidney and nourishing yin, for deficiency of true yin, soreness of waist and knees, night sweats, fatigue and dry mouth. Gui You Pill is used to warm and tonify kidney yang, replenish essence and marrow, and is mainly used for treating kidney yang deficiency, such as chills, impotence and nocturnal emission. Suggestion: Zuogui Pill and Gui You Pill have opposite effects. Dialectical and correct use is effective.