How Heavy Should Chinese Herbal Doses Be? Light for Chronic Disease, Variable for Acute

The Japanese say that the secret not handed down in TCM lies in dosage. The dosage of Chinese herbs determines clinical efficacy, yet dosage is hard to master.

Once a doctor prescribed a formula; the patient took it as directed with no effect. Growing impatient, the patient decocted three doses together and took them, with immediate, striking effect.

Professor Zhao Shaoqin, a great master of China's Warm Disease school, was known in his lifetime for small formulas and light doses. His contemporary, the renowned physician Qin Bowei, assessed him as "an upright, light and agile healer." In Zhao's medical cases one rarely sees large-dose prescriptions, yet his clinical results were outstanding.

The prescriptions left by Japanese TCM masters like Tsumura Shinno (Tumoto Shinno) and Otani Keisetsu were so lightly dosed that they astonished some modern Chinese advocates of heavy-dose prescribing, such as the famed Li Ke. In formulas by these Japanese Kampo physicians, doses of aconite (fuzi) were often no more than 1–3 g, sometimes merely 0.5 g, yet the results were still excellent.

I once liked to use heavy doses. Heavy-dose herbs can, when a patient is near death, achieve a life-saving effect. In recent years I have often joined emergency rescues of critically ill patients; when using TCM decoctions, the doses were sometimes astonishingly large, and the results were excellent—more than once, when other Chinese and Western emergency measures failed, I pulled patients back from death.

But in treating I also made the mistake of overdosing, to the point where patients developed severe side effects; reducing the dose instead produced very good results. These real experiences taught me that dosage is hard to get right.

By the way, Master Li Ke was famous worldwide for heavy dosing. In the last years of his life, many of his patients not only failed to improve but suffered serious side effects; I myself encountered quite a few such patients he had mishandled.

Some TCM physicians argue that herb quality is poor today, so light doses do not work; for a time I believed this too.

But my patients are scattered far and wide. After I write a prescription, most buy the herbs at local pharmacies or TCM hospitals. As long as the formula is good, even very small doses usually work well.

I rather suspect that articles denouncing the unreliability of today's herbs are somewhat sensationalist, and partly an excuse for poor clinical prescribing.

The Japanese, meticulous as they are, attach such importance to clinical herbal dosage because, in studying TCM, they truly noticed how closely dosage and efficacy are linked—hence their exclamation that TCM's untransmitted secret lies in dosage.

After years of clinical practice, while I would not claim to have mastered the secret of dosage, I have worked out some referenceable principles.

For ordinary chronic disease, light doses are preferable to heavy ones, because chronic disease cannot yield rapid results like acute disease; the patient must take medicine long-term, so overly large doses easily damage the spleen, stomach, liver, and kidneys, which is counterproductive.

Even tonifying herbs used for chronic disease should be in small doses. Some tonifying formulas in ancient TCM prescriptions—such as Bazhen Tang (Eight Treasures Decoction) and Shiquan Dabu Tang (Ten Complete Great Tonifying Decoction)—actually use very low single doses. According to ancient medical texts, doses were often under 10 g.

Deficiency and damage disorders require a long period of regulation. Patients weakened by chronic disease also easily show "deficiency unable to accept tonification," so clinically, starting light is more beneficial.

For acute disease—for example, massive bleeding—hemostatic herbs may be used in heavy doses. I have joined rescue efforts for lung and gastric cancer patients with major hemorrhage; conventional herbal doses failed, and Western hemostatic measures failed too, but raising the dose of the hemostatic herb baiji (Bletillae Rhizoma) to 30 g produced obvious hemostasis.

Reading the medical cases of the late renowned Shanghai TCM physician Liu Minshu, I saw he took another approach: he used very light doses of hemostatics like Yunnan Baiyao—0.1 to 0.5 g at a time—but at very short intervals. Liu gave the medicine every fifteen minutes to stop bleeding in an elderly monk with gastric cancer, treating him for about a month with good results.

Li Ke, in his lifetime, was most famous for his outstanding emergency results in many critically ill patients, especially those with heart failure; clinically, his doses of aconite often exceeded 100 g.

These two dosing approaches both differ from the conventional approach and are worth studying by emergency physicians.

Of course acute disease has many categories; not every acute condition is suitable for heavy-dose emergency treatment. Heavy dosing is unsafe and easily causes medical accidents. If a physician lacks dosing experience, light doses may do little harm, but heavy doses carry much higher risk.

So, for safety, heavy dosing must be used cautiously. My own approach is to start with small doses, or to decoct more and take less, observing the patient's response as I go. If the response is good and side effects are absent or minor, I steadily increase the dose until the patient's problem is resolved.

Of course, the foundation of prescribing is accuracy. Professor Zhao Shaoqin once said that his father, Zhao Wenkui—the last director of the Imperial Medical Academy in the Qing dynasty—had taught him that prescribing medicine to cure disease is like finding the right key for a lock: it takes skill, not brute force. Once the right herb is chosen, it is like finding the right key—the lock opens with a light turn, and the disease is cured easily.

But I believe that even if Zhao Wenkui himself returned, he could not guarantee finding the right key to every illness every time. So the true realm of "upright, light, and agile" is not easy to reach. A clinician must keep thinking about dosage; long accumulation will gradually form his own effective dosing approach.