Generally speaking, TCM causes for impotence are familiar to us, because Western medicine blames them as well. Causes include emotional stimulation, excessive sex, pathogenic invasion, improper diet, injuries, long-term illness and constitutional weaknesses. However, its TCM's understanding of how these factors contribute to impotence that differs. The kidneys store essence (jing), dominate reproduction and control the anterior and posterior orifices (urethra and anus). Normal sexual functioning depends on an abundance of kidney-qi that comes from the vaporization of kidney essence. In ancient China, impotence was mainly attributed to overstrain and kidney deficiency. Liver dysfunction was also thought to contribute to the problem as well because the liver rules the tendons and its meridian (Jue Yin Liver Meridian)circulates around the genitals and controls their actions. Details of this process were described in chapter 10 of the Lingshu (The Vital Axis). "Dysfunctions of male genitalia are due to tendon diseases of the Jue Yin Liver Meridian; if damaged by excess sexual activity, it leads to impotence; if damaged by cold evils, it leads to genital retraction and if damaged by heat evils, it leads to prolonged penial erection." Based on ancient established theories, modern TCM physicians further elaborated on the mechanism of impotence. Spleen, heart and emotional problems are now also associated with its development. The ways they affect the body are as follows:

1. Debility of the vital gate fire This refers to a morbid condition that is caused by serious depletion of kidney yang. Debility of the vital gate fire means the kidneys fail to warm up the internal body leading to hypo-functioning of all the physiological activities thus affecting a decline in sexual and reproductive functions.
2. Fear or fright damaging the kidneys In TCM, emotional reactions are closely associated with organ function. Particular emotions can induce physiological changes. For impotence, sudden fear can lead to the disordered movement of qi (vital energy) and sudden fright can cause an unhealthy descention of qi. Both unhealthy emotions of fear and fright are emotions of the kidneys and will in turn affect kidney function so that they cannot control sexual activity and sexual performance properly.This condition may occur when there is a sudden interruption during coitus or from other disturbance that causes fearful and frightened emotions.
3. Stagnation of liver-qi One of the functions of the liver is to balance emotions. Normal emotional health depends on the harmony of qi and blood flowing smoothly, and these functions are governed by the liver. When the liver keeps a proper flow and release of qi (vital energy) and blood, a relaxed internal, emotional environment is created. Emotional disturbances, especially frustration and anger, impair the liver's regulating functions and a condition termed "stagnation of liver-qi" results. Stagnation of liver qi affects the liver meridian and means the liver cannot nourish the genital tendons and muscles that are in the pathway of this meridian. Impotence can then result.
4. Spleen and heart deficiency In TCM, thoughts originate from the spleen and ripen in the heart. Therefore, excessive pensiveness exhausts a lot of qi and blood from the heart and affects the spleen's transformation and transportation functions. A deficiency of blood and qi (vital energy) then arise leading to an ultimate inability of these substances to be transformed into semen, and this renders the penis incapable of an erection.
5. Downward accumulation of dampness-heat Over consumption of heavy and greasy foods produce excess heat evils in the stomach and living or working in damp environments can draw in dampness evils easily. When these heat and dampness evils accumulate in the middle burner, the liver and bladder functions become depressed. Ultimately these dampness-heat evils progress further down along the liver meridian to the testes and hinder blood flow resulting in impotence.
6. Obstruction from blood Surgeries, external injuries or long-term attack by pathogens in the meridians of the perineum region (area occupied by uro-genital passages and the rectum in pelvis), result in stagnation of blood and qi (vital energy) in the area. Prolonged periods of stagnation lead to sluggish blood and qi flow and undernourishment of the external genitalia, which in turn gives rise to impotence.

Development of impotence from a TCM perspective.
A. debility of the vital gate fire
B. fear and fright damaging the kidneys
C. stagnation of liver-qi
D. spleen and heart deficiency
E. downward accumulation of dampness-heat
F. obstruction from blood stasis