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[Shengyong] (Raw use): Pungent and warm, it drives out cold pathogens and releases the exterior.
[Paozhi] (Processed): Becomes pungent, bitter, and greatly hot; it eliminates stomach cold and stabilizes the middle jiao (Pungency disperses, but processing adds slight bitterness, so its action is stationary rather than moving, unlike Fuzi which moves without stabilizing).
It warms the meridians and stops bleeding (processed to blackness, it stops hematemesis, epistaxis, and various other bleedings, as "red stops when seeing black"); it calms vomiting, resolves phlegm, and removes deep-seated cold from the zang-fu organs.
It can eliminate evil and generate newness, allowing Yang to grow and Yin to lengthen; therefore, it is suitable for conditions of hematemesis, epistaxis, and lower body bleeding where there is Yin deficiency without Yang consolidation.
It can also guide blood-tonifying herbs into the Qi level to generate blood; thus, it is suitable for fever due to blood deficiency or high fever after childbirth (this is not excess heat, but internal heat generated by Yin deficiency; superficial-releasing and cold-natured drugs are contraindicated. Ganjiang enters the Lung meridian to benefit Qi flow; it enters the Liver meridian to guide blood herbs in generating blood, so it is used with Yin-tonifying herbs. This is the treatment method of "treating heat with heat" (reversal treatment), so it also treats chronic redness of the eyes).
Guided by Heifuzi (Black Prepared Aconite Root), it enters the Kidney meridian to dispel cold-dampness and restores Yang in cases of pulselessness and absence of Yang (e.g., Sini Tang, Baitong Tang, Jiangfu Tang by Zhang Zhongjing all use it).
Combined with Wuweizi, it benefits Lung Qi and treats cold coughs (the Lung dislikes cold).
It dries Spleen dampness and tonifies Spleen Qi (the Spleen dislikes dampness); it unblocks Heart Yang and tonifies Heart Qi (Bitter enters the Heart); it opens the five zang and six fu organs, unblocks the joints of the four limbs, and circulates the collaterals.
It treats cold bi syndrome, cold痞 (fullness), regurgitation, and diarrhea.
However, excessive use damages Yin and consumes Qi; pregnant women should avoid it (Pungent and hot nature can move blood. Wang Haogu stated: Taking Ganjiang to treat the middle jiao inevitably causes Qi to rebel upwards, so it should be assisted by Dazao. Li Dongyuan stated: It should be moderated with Gancao).
The mother ginger dried in the sun is called Ganjiang; processed to blackness is called Heijiang.

[Yam]
Ancient name: Shuyu.
Benefits the Spleen and Lung, astringes Essence and Qi.
Its white color enters the Lung; its sweet taste returns to the Spleen.
Entering the Spleen and Lung meridians, it tonifies deficiencies and clears deficient heat (Yin deficiency leads to internal heat; tonifying Yin thus clears heat).
It consolidates the intestines and stomach, moistens skin and hair, transforms phlegm-saliva, and stops diarrhea and dysentery (by promoting diuresis to transform phlegm and stop diarrhea. *Baiyi Fang*: Yam, half raw and half stir-fried, taken with rice drink. Treats Jin Kou Li [dysentery with inability to eat]).
The Lung is the mother of the Kidney, so it also tonifies the Kidney and strengthens Yin, treating deficiency damage and consumptive disease (Wang Lu stated: In Bawei Wan, Yam is used to strengthen Yin); the Spleen is the child of the Heart, so it also benefits Heart Qi (the child makes the mother full), treating forgetfulness and seminal emission (Wang Ang notes: Yam's nature is astringent, hence it treats seminal emission and diarrhea, though previous authors did not mention its astringency).
Crushed raw and applied externally to carbuncles and sores, it reduces swelling and hardness (Yam can reduce heat-swelling; by tonifying Qi, pathogenic stagnation dissipates naturally. Zhu Danxi stated: Yam that tonifies Yang Qi and generates tissue can reduce swelling and hardness).
Those that are white in color and firm in texture are used for medicine.