Blood Stagnation

In TCM, Qi is described as the 'commander of Blood' because it is the driving force that keeps blood moving through the vessels. When Qi becomes stuck or stagnant, most commonly due to emotional stress, frustration, or suppressed anger, the blood it is supposed to push along also slows down and eventually stagnates. The Liver is the organ most responsible for keeping Qi flowing smoothly throughout the body. Prolonged emotional strain impairs the Liver's ability to do this job, and the resulting Qi stagnation gradually leads to Blood stasis. This is the most common mechanism by which Blood Stagnation develops, and it explains why emotional health and circulation are so deeply connected in Chinese medicine.

If the body's Qi is too weak, it simply lacks the power to push blood through the vessels at a healthy pace. Think of Qi as the pump pressure in a water system: if the pressure drops too low, the water barely moves and starts to pool. Qi deficiency can result from chronic illness, overwork, poor nutrition, excessive bleeding, or simply ageing. The Heart and Spleen are the main organs that generate and move Qi and Blood, so weakness in either of these systems commonly leads to sluggish blood flow and eventual stasis. A classical text, the Yi Lin Gai Cuo, describes this clearly: when original Qi is deficient, it cannot reach the blood vessels, and stagnation results.

Cold causes contraction and congealing. When cold invades the body (from exposure to cold weather, swimming in cold water, or consuming excessive cold and raw foods), the blood vessels contract and the blood itself thickens and slows, like oil becoming viscous in cold temperatures. This is especially common in the lower abdomen and uterus, which is why many women experience worse menstrual pain in winter or after consuming icy foods. Internal cold from Yang deficiency (the body's warming function being too weak) produces the same effect over time.

Excessive heat in the body can also cause Blood stasis, though by a different mechanism. Heat causes fluids to evaporate and blood to thicken, making it more viscous and prone to stagnation. Severe, prolonged heat can also damage the vessel walls, allowing blood to leak out and pool in tissues. Febrile diseases, chronic inflammation, or constitutional excess heat can all lead to this pattern. The resulting stasis often combines with the heat itself, creating a 'heat and stasis intertwined' condition that requires both cooling and blood-moving treatment.

Physical injury is the most straightforward cause of Blood stasis. A fall, blow, surgery, or any tissue damage causes blood to leak out of the vessels and pool in the surrounding tissues, forming a bruise or haematoma. In TCM, this 'blood outside the vessels' is called 'departed blood' (离经之血) and is considered stagnant by definition. If the body cannot reabsorb and clear this leaked blood promptly, it becomes a source of ongoing stasis that blocks the formation of new, healthy blood and impairs local healing.

Any form of bleeding, whether from the nose, uterus, digestive tract, or elsewhere, can lead to Blood stasis. The classical text Xue Zheng Lun (Treatise on Blood Disorders) explains that all blood that has left the normal vessels is already a form of stasis. If this blood is not promptly expelled from the body or reabsorbed, it accumulates internally, obstructing the generation of fresh blood and creating further stagnation. This is why TCM treatment for bleeding often includes herbs that both stop bleeding and dispel stasis, such as San Qi (Notoginseng).

Phlegm and Dampness are thick, heavy substances that can accumulate in the body when digestion is weak or fluid metabolism is impaired. When these substances clog the vessels and tissues, they physically obstruct blood flow and create conditions for stasis. Blood stasis and Phlegm often reinforce each other in a vicious cycle: stagnant blood impairs fluid metabolism, generating more Phlegm, while Phlegm further blocks blood circulation. This combined pattern (痰瘀互结) is particularly stubborn and is commonly seen in conditions involving lumps, nodules, and tumours.

Physical movement is essential for maintaining healthy blood circulation. Prolonged sitting, bed rest, or a generally inactive lifestyle allows blood to slow and pool, particularly in the lower extremities and pelvis. TCM has long recognised this connection: classical teachings note that prolonged sitting injures the flesh and Spleen, both of which are involved in maintaining healthy blood flow. Modern understanding of conditions like deep vein thrombosis from long flights or bed rest mirrors this ancient observation closely.