Classical and Formulary Prescriptions
Classical and Formulary Prescriptions
This domain tests formula structure, indications, modifications, and safe prescribing of classical and standard formulas.
Core rules
- A formula is organized as sovereign (chief), minister, adjuvant, and courier. The sovereign addresses the main pattern; the minister reinforces; the adjuvant addresses accompanying signs or toxicity; the courier harmonizes and directs.
- Indications are pattern-based, not disease-name-based. Gui Zhi Tang treats Taiyang exterior deficiency with sweating and a floating slow pulse; Ma Huang Tang treats exterior excess without sweating.
- Xiao Chai Hu Tang targets Shaoyang: alternating chills and fever, bitter taste, dry throat, dizziness, wiry pulse.
- Si Jun Zi Tang tonifies Spleen qi; Liu Wei Di Huang Wan nourishes Kidney yin; Xue Fu Zhu Yu Tang invigorates blood and opens chest.
- Modifications follow signs: add heat-clearing herbs for heat, omit warming herbs for yin deficiency. Dose ratios and decoction method can change the formula character.
Worked example
A patient has aversion to cold, spontaneous sweating, headache, and a floating slow pulse after chills. This fits Gui Zhi Tang, not Ma Huang Tang. Reasoning: sweating indicates exterior deficiency and ying-wei disharmony; Ma Huang Tang would aggravate sweating. The principle is harmonize ying and wei, release exterior mildly. If the patient develops high fever and thirst, the pattern has changed and the formula must be modified or reassessed.
Traps
Do not use a classical formula because the disease name matches. Do not ignore contraindications, pregnancy, or toxic herbs. Do not convert historical doses blindly. Do not continue a formula after the pattern transforms.