If external Wind-Heat is not expelled, it easily progresses to the Interior and turns into interior
Heat, usually affecting the Lungs and/or the Stomach. At this stage, corresponding to the
Bright-Yang stage of the 6 Stages or Qi Level of the 4 Levels, there is a high fever and
pronounced symptoms of Heat such as intense thirst, profuse sweating, a Red tongue and a Rapid
pulse. This type of Heat during a febrile disease tends to injure fluids very quickly and cause
dryness. This affects Lungs, Stomach and Intestines where it dries up the stools and causes
constipation.

Heat that causes dryness and constipation during a febrile disease is called Fire. Constipation
with abdominal pain and pronounced dryness are the main symptoms which distinguish Fire
from Heat. It is for this reason that at this stage of a febrile disease with constipation (or merely
with dry stools), the treatment principle is to drain Fire by moving downwards. In herbal
medicine, the practitioner uses one of the three moving-downwards formulae, i.e. Da Cheng Qi
Tang Great Conducting Qi Decoction, Xiao Cheng Qi Tang Small Conducting Qi Decoction or
Tiao Wei Cheng Qi Tang Regulating the Stomach Conducting Qi Decoction. With acupuncture,
one can use the combination of T.B.-6 Zhigou with SP-15 Daheng.

Pathology

As for the pathology, the organs mostly involved in constipation are the Stomach, the Large
Intestine, the Spleen, the Liver and the Kidneys; the key factors for a healthy bowel function are
a good supply of fluids in Stomach and Intestines and a strong Qi to move the stools along the
digestive system.

Stomach

The Stomach is the origin of fluids and is very closely linked to the Intestines. If the Stomach is
affected by Heat or if it suffers from Yin deficiency, the fluids are deficient in the Stomach and
Large Intestine and the stools dry up so that they cannot be moved properly.

In acute febrile diseases at the Qi Level (of the 4 Levels) there is often Fire drying up the fluids
in the Stomach and Large Intestine and therefore the stools. This causes constipation. In this case
the stools are very dry.

Large Intestine

The Large Intestine is functionally related to the Stomach (within the Bright-Yang channels) and
is affected by Stomach-Heat or Stomach-Yin deficiency as described above. This causes
constipation from Heat or Yin deficiency.