Scientific Chinese Medicinal (SCM) prescriptions can be categorized into formula-stacking prescriptions, herb-by-herb prescriptions, or a mix of both. Single herbs refer to individual medicinal ingredients, such as Astragalus, Red Dates, and Goji Berries. A prescription composed entirely of single herbs is called a herb-by-herb prescription—a custom prescription composed of individual herbs.
Pre-made or classical formulas are traditional prescriptions made of specific combinations of single herbs. For example, Four Ingredients Decoction consists of four herbs, while Ten Major Tonics Decoction contains twelve. Since these formulas are commonly used, pharmaceutical companies pre-make many well-known ones into powdered form for sale. Pre-made formula names typically end with words like "Tang" (decoction), "San" (powder), or "Wan" (pill). A prescription that combines multiple formulas or adds a few single herbs is called a formula-stacking prescription.
To use a restaurant analogy, formula-stacking is like a set menu—only a few fixed combinations are available. A herb-by-herb prescription, on the other hand, is like an exquisite buffet where you pick each dish individually. In terms of clothing, formula-stacking is like ready-to-wear garments, limited to sizes S, M, L, and XL, while a herb-by-herb prescription is like a custom-tailored outfit, meticulously measured and stitched to fit your exact proportions. It's also like writing an essay: using idioms is akin to formula-stacking, where a single phrase carries multiple meanings, whereas writing word by word without idioms resembles a herb-by-herb prescription—more deliberate and thoughtful. In programming terms, formula-stacking is like calling pre-built library functions that execute a series of operations, while a herb-by-herb prescription requires writing each instruction manually to achieve the desired functionality.
Traditionally, TCM prescriptions were always composed herb by herb. Although ancient practitioners used classical formulas, the herbs still had to be weighed individually. However, since the advent of Scientific Chinese Medicinal (SCM), formula-stacking has become the mainstream. The advantage of formula-stacking is faster dispensing—no need to measure each herb separately. But the biggest drawback is that all herbs in a pre-made formula are already cooked together, making it impossible to remove unwanted herbs or adjust their ratios. Even though ancient doctors used formulas, they could modify them based on the patient's condition because the herbs were weighed individually. In contrast, SCM formulas can only have herbs added, not subtracted, and their proportions cannot be easily adjusted. What's the issue with this? Take the commonly used Four Ingredients Decoction as an example: this formula contains four herbs, but it's not rigid. For patients with deficient heat, the warm-natured Prepared Rehmannia can be replaced with the cooler Raw Rehmannia, Stir-fried White Peony can be substituted with Raw White Peony, and the hot-natured Sichuan Lovage can be reduced or omitted. If the patient has blood stasis or poor circulation, White Peony can be changed to Red Peony, Angelica Sinensis can be replaced with Angelica Tail, and Sichuan Lovage can be increased. In other words, a flexible prescription is a "living" prescription, while rigid application makes it a "dead" one. SCM formulas are "two-thirds dead" because they're pre-cooked—herbs can only be added, not removed, and their ratios can't be adjusted to suit the patient.Another issue with SCM is the limited selection of pre-made formulas—it depends on what the pharmaceutical companies produce. If a certain formula isn't available, the physician must compose it from single herbs.
For TCM practitioners, formula-stacking is naturally easier and more convenient—like serving a set menu or shooting buckshot, where some dishes may not suit the patient's taste, but the whole set is delivered anyway. In contrast, herb-by-herb prescriptions require more deliberation and effort in dispensing, but they allow for greater precision, enhanced efficacy, and avoid unnecessary herbs. It's like a custom-made gourmet meal where every dish is tailored to your liking, ensuring you finish every bite. Herb-by-herb prescriptions offer infinite flexibility, streamlined herb usage, and aren't constrained by the limited selection of SCM formulas. Their therapeutic effects surpass formula-stacking, making them the preferred choice for meticulous practitioners like myself.