An excess pattern is when disease, pain, or dysfunction is a result of excessive environmental factors, poor diet, pestilence, or miscellaneous factors overwhelming the body's defensive capabilities. As the Neijing Suwen (a foundational text of Chinese Medicine) goes:
When the environmental pathogenic factors (邪, Xié) are overabundant they cause Excess. Deprivation of refined substances (Nutritive Qi, Defensive Qi, Mind and Essence) causes Deficiency.
Although it is difficult to generalize, the main symptoms of an Excess pattern are acute disease, restlessness, irritability, a strong voice, coarse breathing, pain aggravated by pressure, high-pitch tinnitus, scanty urination, constipation and a pulse of the Full type.
To show that it is difficult to generalize some of the above symptoms cannot, strictly speaking, be categorized as Excess symptoms. Just to give one example, constipation is included among the Excess symptoms because it is often caused by stagnation or by Heat, but there are also Deficient causes of constipation, such as Blood or Yin deficiency.
Moreover, the above symptoms are too general to be of use by practitioners. Many examples could be given of Excess conditions. First of all, any exterior condition due to invasion of exterior Cold, Wind, Damp or Heat is Excess by definition, as it is characterized by the presence of those exterior pathogenic factors.
Any interior pathogenic factor also gives rise to an Excess condition, provided the body’s Qi is strong enough to engage in a struggle against such pathogenic factors. Examples of these are interior Cold, Heat, Dampness, Wind, Fire and Phlegm.
A condition is also categorized as Excess when caused by retention of either food or fluids, or by stagnant Blood or Qi. It's rather logical: if retained or stagnant the body tends to reacts acutely.
Conditions characterized by a combination of Excess and Deficiency arise when there is a pathogenic factor but its influence is not very strong, while the body’s Qi is weak and not reacting properly against it.
Examples of conditions of Deficiency complicated with Excess are Kidney-Yin deficiency with rising of Liver-Yang, Spleen-Qi deficiency with retention of Dampness or Phlegm, deficiency of Blood with stagnation of Blood and deficiency of Qi with stagnation of Blood.