Gan jiang fu zi tang
gan jiang 3 fu zi 6
When precipitation has been used, yet sweating is then promoted so that the person in the day time is vexed, agitated, and sleepless, but by night time becomes peaceful and retching, thirst, exterior signs, and great generalized heat are all absent, and the pulse is sunken and faint, gan jiang fu zi tang governs.
During the day the person is vexed because the yang is floating up and causing mental unrest but at night this disappears. Night time is the time of yin so the yang is less and peaceful.
Gan jiang, Zingiberis rhizoma, dried is warm (or hot) pungent and astringent. Gan jiang is the main herb to warm the tai yin level and treat excessive dampness by introducing yang ming dryness in tai yin dampness.
Fu zi, Aconiti radix lateralis praeparata is pungent dispersing of liver blood and the ministerial fire in the san jiao. It is pungent dispersing of the heart and kidneys. It is pungent dispersing of the tai yang channels. It is pungent dispersing of excess water.
The hot pungent stagnant heat from gan jiang anchors the dispersing warmth of fu zi. There is a saying that fu zi is not hot without gan jiang. We see this pair in si ni tang. They warm the interior and especially of shao yin and tai yin.