There are more than 100,000 prescriptions transmitted in oriental medicine. Unlike acupuncture, herbs chemically interact with a body and draw physiological change.

The huge number of prescriptions share Shang Han prescriptions as a root. Historically Shang Han formula are the eldest group of formula passed down through generations and kept being modified.

The prescriptionology in oriental medicine have a few branches. Some practitioners including Heayoon Park experience Shang Han prescriptionology work wonderfully with very low recurrence rate. However, since it's the oldest branch, its key wisdom to match a precise formulus and a pathologic condition has been somewhat lost. It's hard to find any practitioner who freely utilizes Shang Han formula and realize their full potential.

Some Korean herbalists are re-defining the system of Shang Han formula, and their work is mediated by a medieval Janpanes herbalist, Yoshimaz Todo. They believe Shang Han formula is constructed to expel pathogens out of our body through sweat, urine, and stool - vomitting is another one, but rarely used. Once the pathogens are removed completely, patients show very steady health.