(1) Characteristics of Slippery Pulse The slippery pulse (hua mai) is one of the most common and significant pulse patterns in clinical practice. Its pulse quality is exceptionally smooth, indicating an abnormal state, as its fluidity exceeds that of a normal pulse. The sensation of the pulse flows swiftly beneath the fingers. It is particularly noticeable in many pregnant women around the third to fourth month of pregnancy, where the pulse often presents as slippery. By the fifth to sixth month, the pulse may feel even more pronounced. A slippery pulse is characterized by an unusually smooth and flowing sensation, which can even be described as excessively fluid. The sensation of a slippery pulse is such that the time difference between feeling the pulse at the ring finger and the index finger is very short; it flows from the ring finger to the index finger almost instantaneously. As soon as the ring finger detects the pulse, the index finger also immediately feels it. Of course, for beginners, this can be challenging, as the difference may only be a fraction of a second. However, with practice, one can easily perceive that as soon as the finger touches the pulse, the sensation of the pulse comes alive. In contrast, a choppy pulse (se mai) has a longer time difference between the two fingers, although the actual difference is still only a fraction of a second. Therefore, we need to train our tactile sensitivity. (2) Mechanisms and Diagnostic Significance of Slippery Pulse There are four main mechanisms that lead to a slippery pulse: first, heat invading the Qi level, predominantly Yangming heat; second, phlegm; third, pregnancy; and fourth, food stagnation, which often generates some heat, making the pulse more slippery. Thus, the notion that pulse patterns indicate specific diseases is debatable; we cannot simply say that pregnancy is a disease. Therefore, we propose the mechanisms behind pulse formation to better explain the essence of certain clinical phenomena. 1. Heat Invading the Qi Level (Predominantly Yangming Heat) When heat invades the Qi level, it causes a rapid pulse. If the pulse does not significantly accelerate, it can still lead to very rapid blood flow, which manifests as an unusually smooth pulse. This indicates that the blood is flowing rapidly, not that the pulse rate is fast. Since Yangming is a channel rich in blood and Qi, once there is heat in the Yangming Qi level, the influence of the pathogenic heat on the blood becomes evident, promoting a very smooth blood flow. Clinical examples of slippery pulses caused by Yangming heat are abundant in both clinical practice and classical texts. For instance, in the “Shang Han Lun” (Treatise on Cold Damage), it states: “If the pulse is slippery and there is a feeling of cold, there is heat in the interior; Bai Hu Tang is indicated.” Another example states: “In Yangming disease, if there is delirium and tidal fever, and the pulse is slippery and rapid, Xiao Cheng Qi Tang is indicated.” These are examples of slippery pulses caused by Yangming heat. 2. Phlegm The mechanism by which phlegm leads to a slippery pulse is difficult to articulate, whether from a TCM or Western medical perspective, or from a physiological or pathological standpoint. However, it is indeed a clinical reality. Patients with phlegm, especially those with wind-phlegm, often present with an exceptionally slippery pulse. For example, a patient with shoulder periarthritis who has had the condition for several years may have a slippery pulse upon examination, indicating phlegm obstructing the meridians. Treatment with a few doses of medicine can resolve the issue. I once treated a patient with a twisted ankle who could not walk or climb stairs; upon examining the pulse, it was also slippery, indicating phlegm obstructing the meridians. The treatment involved using Zhu Li (bamboo sap) combined with ginger juice, which yielded significant results. The reason for using Zhu Li and ginger juice was due to the presence of heat and phlegm-heat, as evidenced by the patient’s red tongue and thick coating. The key diagnostic point here is the slippery pulse, which is almost the only distinguishing feature. Without the ability to palpate the pulse, it would be impossible to differentiate. In contrast, a pulse obstructed by wind-dampness is often not smooth and may even be choppy. If the pulse is slippery, it indicates phlegm obstruction; if it is choppy, it suggests blood stasis. If the pulse is slippery, we must eliminate phlegm. This is not a miraculous treatment but rather a traditional TCM principle passed down from our ancestors, which we must learn to apply. The pulse is an important tool for syndrome differentiation; if pulse diagnosis is inadequate, it becomes challenging to distinguish between conditions. The differentiation between phlegm obstructing the meridians and blood stasis, as well as between wind-dampness and blood stasis, primarily relies on the pulse. However, why does phlegm obstruction lead to a slippery pulse? I find it difficult to explain the mechanism clearly. Phlegm can obstruct the heart’s pericardium, leading to confusion, and the pulse is also slippery. Therefore, all phlegm-closure conditions present with a slippery pulse, which I cannot explain, but it is a fact. A slippery pulse, excessively smooth, can indicate a lack of control, leading to potential fatality. However, if a slippery pulse is due to heat causing the fluids to transform into phlegm, it does not necessarily mean that cold phlegm cannot also present as slippery. In the Yang He Tang syndrome, patients with phlegm can also exhibit a slippery pulse, so it cannot be solely attributed to excess heat. Otherwise, how could we dare to use Lu Jiao Shuang (deer antler powder), Lu Jiao Mo (deer antler glue), etc.? The primary formula for treating phlegm obstructing the meridians is Zhi Mi Fu Ling Wan (Zhi Mi and Poria Pill). Of course, if there is also Yang deficiency, Yang He Tang can be used, with a heavy dose of Bai Jie Zi (white mustard seed). Decades ago, while participating in rural education, I treated a landlord who had a twisted ankle for over a decade. I secretly prescribed Zhi Mi Fu Ling Wan, and within ten doses, the ankle that had been twisted for years was healed. The ingredients of Zhi Mi Fu Ling Wan include Fu Ling (Poria), Feng Hua Nao (wind-processed mirabilite), Ban Xia (Pinellia), Zhi Ke (bitter orange), and ginger juice. Zhu Danxi believed that adding ginger juice could open the meridians, and he was correct! What is Feng Hua Nao? It is naturally wind-processed mirabilite. Some people artificially wind-process it; mirabilite, when exposed to wind for a long time, loses its water content. What does this mean? Mirabilite is a crystalline compound formed by sodium sulfate and water molecules. Under a microscope, mirabilite appears as elongated crystals, resembling granulated sugar. If it undergoes prolonged wind exposure, it loses its crystallization water, and some old herbalists, when faced with difficulties, would place mirabilite in a high place to let it wind-dry for several months. This process transforms the crystalline substance into a very fine powder, much finer than table salt, resulting in a white powder that is no longer in its semi-transparent state. This white powder is much finer and whiter than white sugar. Feng Hua Nao is quite peculiar; when ingested, mirabilite causes diarrhea, while Feng Hua Nao does not. However, the issue now is that due to the low price of Feng Hua Nao, no one is using it anymore. What should we do? Xuan Ming Fen (Xuanming powder) can be used as a substitute; it is the main ingredient in Zhi Mi Fu Ling Wan and is effective in dispelling wind and phlegm. The efficacy of Xuan Ming Fen is about one-third to one-half that of Feng Hua Nao. It is still effective, just less efficient, requiring a longer duration of use. There is also a so-called side effect: taking Xuan Ming Fen may cause slight diarrhea. But this is not a side effect; it is actually its intended effect. 3. Pregnancy and Normal Women 3-5 Days Before Menstruation Pregnant women may have a slippery pulse, but it is not mandatory; it is simply more common. The pulse during pregnancy can indicate a pathological state, while a normal pulse is soft and calm. Moreover, most healthy individuals may also exhibit a slippery pulse. A slippery pulse in pregnant women reflects the body’s accumulation of blood to nourish the fetus. 4. Food Stagnation Leading to Heat The cause of a slippery pulse due to food stagnation primarily lies in the stagnation itself, rather than heat. Did we not discuss in the section on “The Value of Pulse Diagnosis” that in the “Shang Han Lun” (Treatise on Cold Damage) it states: “This indicates a desire to form food stagnation… the pulse is slow”? This slow pulse can be caused by food stagnation, but why can food stagnation also lead to a slippery pulse? The food stagnation that leads to a desire for food stagnation is often accompanied by dampness, resulting in a slow pulse; whereas food stagnation that leads to a slippery pulse tends to generate heat, thus becoming slippery. Treatment should focus on clearing heat, but primarily on digesting food and relieving stagnation. 5. Normal Individuals Healthy individuals may exhibit a slightly slippery pulse. A slightly slippery and gentle pulse in healthy individuals indicates a harmonious balance of Ying and Wei (nutritive and defensive Qi) and a fullness of Qi and blood. (3) Diagnostic Significance of Slippery Pulse Differentiation 1. Slippery pulse caused by pathogenic excess is characterized by a slippery and forceful pulse, often accompanied by rapid or rapid pulses, indicating heat in the Qi level; if accompanied by a floating pulse, it suggests wind-phlegm in the lungs; if accompanied by a sinking pulse, it indicates phlegm-heat in the interior; if accompanied by a slow or wiry pulse, it suggests cold-phlegm. 2. In pregnancy, the slippery pulse is soft and calm. 3. In normal individuals, the pulse is slightly slippery and gentle.
