0.5–1 cun vertically or obliquely from medial towards lateral.
Caution: Needling may be painful.
Gongsun SP-4 is an important point with various functions.
First of all, it harmonizes the Middle Burner, mainly the Spleen and Stomach. In fact, it can be indicated for any Excess patterns there, such as Dampness in the epigastrium, Stomach Blood Stagnation, Stomach Heat or Stomach Rebellious Qi. Typical manifestations include fullness, distension or pain in the epigastrium and abdomen.
Stronger Spleen and Stomach functions benefit the Intestines. Thus SP-4 also regulates this Organ and treat symptoms such as borborygmi, diarrhoea and undigested food in the stools.
Many of SP-4's other functions are due to its being the opening point of the Penetrating Vessel (Chong Mai). Most importantly, the vessel is considered the 'Sea of Blood' and the 'Sea of the 12 Channels'. It has influence over the Uterus functions such as menstruation or lochia. Gongsun SP-4 can be stimulated to regulate the Vessel, so as to stop symptoms such as painful period or excessive Uterus bleeding.
On the other hand, a well functioning Spleen also helps to stop various bleeding (eg: Intestines or Uterus) because stronger Spleen Qi can hold Bloods in the veins.
Gongsun SP-4 is also the Connecting-Luo point of the Spleen Channel, which generally stops bleeding of the relevant Channel as well as the Penetrating Vessel.
Furthermore, the Penetrating Vessel goes through the Heart. Thus Gongsun SP-4 is able to regulates the Heart and the chest. It also calms the Mind by opening the Heart Orifice. Typical manifestations includes depression, anxiety, insomnia, mental restlessness as well as chest pain and stiffness.
Finally, one of the Penetrating Vessel's branches go to the sole, big toe and the arch of the foot. SP-4 regulates the Vessel, so as to ease pain, coldness and numbness in these parts of the body.