Draining-precipitant agents

Medicinals that promote defecation either by causing diarrhea or by lubricating the intestines and that are used in draining-precipitant formulas.

Draining-precipitants are often referred to as purgatives. However, while the English term purgative connotes cleansing, the central crux of the Chinese medical concept of xiè xià yào connotes a downward movement. This is reflected in the choice of the English term draining-precipitant, referring to an agent that promotes downward movement.

Subcategories

Draining-precipitants are divided into three categories:

• Offensive precipitant agents, which powerfully free the stool and clear heat.
• Moist precipitant agents, which moisten the intestines and free the stool.
• Drastic water-expelling agents, which treat severe water accumulations and severe phlegm-rheum.

Draining-precipitants are predominantly cold in nature and bitter in flavor. All enter the large intestine channel. All are downsinking.

Properties

Nature: Mostly cold.

Flavor: Mostly bitter. Moist precipitants are generally sweet.

Channel entry: All enter the large intestine channel. All drastic water-expelling medicinals also enter the lung channel; most of them also enter the kidney channel. A few agents have other additional channel entries.

Toxicity: All drastic water-expelling medicinals are toxic.

Bearing: Downsinking.

Actions And Indications

Draining-precipitant medicinals are used for all kinds of constipation. By freeing the stool, they can also eliminate various kinds of evil qì in the treatment of numerous interior repletion patterns.

Offensive Precipitant Agents

Offensive precipitants have a powerful stool-freeing effect in the treatment of constipation. They also clear heat.

Free the stool: Offensive precipitants treat any type of constipation, especially heat constipation or any repletion heat accumulation and stagnation in the digestive tract. When appropriately combined with medicinals from other categories, they can also be used for the following conditions:

• Cold constipation with abdominal pain.
• Dysentery with bloody stool and tenesmus due to damp-heat accumulating and stagnating in the large intestine.
• Food accumulation manifesting in distension and fullness in the stomach duct and abdomen, aversion to food, and diarrhea with ungratifying defecation.
• Worms in the digestive tract (and intestinal parasites).

Clear heat and drain fire: Draining-precipitants tend to have a powerful heat-clearing toxin-resolving action that enables them to eliminate heat evil. This action is called raking the coals from under the cauldron. They can be used in the absence of constipation, as in the following:

• Damp-warmth with vigorous heat effusion, vexation and agitation, and in severe cases delirious speech;
• Exuberant heat in the bowels and viscera with fire qì flaming upward, giving rise to clouded head, headache, painful red swollen eyes, painful red swollen throat or gums, or vomiting of blood, coughing of blood, or nosebleed due to frenetic movement of hot blood.

Acute abdomen: In recent clinical research it has been found that draining-precipitants can be combined with qì-moving, blood-quickening, and heat-clearing medicinals to treat numerous acute abdomen conditions characterized primarily by abdominal distension, abdominal pain, and constipation. Examples of such conditions are acute cholecystitis, pancreatitis, biliary ascariasis, and intestinal obstruction. The traditional basis for these treatments lies in the maxims the six bowels fulfill their functions when there is free flow and when there is stoppage there is pain; when there is no stoppage, there is no pain.

Moist Precipitant Agents

Moist precipitants moisten the intestines to facilitate defecation in patients suffering from dry stool. They do not usually cause diarrhea. Moist precipitants are mostly plant seeds. They tend to be sweet in flavor and balanced in nature. Besides the medicinals presented in this section, several other medicinals moisten the intestines, including:zǐ sū zǐ (Perillae Fructus), guā lóu zǐ (Trichosanthis Semen), bǎi zǐ rén (Platycladi Semen), xìng rén (Armeniacae Semen), jué míng zǐ (Cassiae Semen), dāng guī (Angelicae Sinensis Radix), ròu cōng róng (Cistanches Herba), and raw hé shǒu wū (Polygoni Multiflori Radix).

Drastic Water-Expelling Agents

Drastic water-expelling medicinals are extremely potent draining-precipitants that cause continual watery diarrhea to remove water-damp from the body. They are used to relieve water swelling and phlegm-rheum due to congestion of water-damp when medicinals that disinhibit water and percolate dampness fail to work. In particular, they treat:

• Water swelling with distension and fullness and inhibited urination;
• Drum distension, i.e., water accumulating in the abdomen with abdominal fullness and pronounced distension;
• Phlegm-rheum, in particular, rheum collecting in the chest and rib-side with distension and pain, cough, panting, and shortness of breath;
• Mania and withdrawal or epilepsy due to phlegm obstructing the orifices of the heart.

The use of drastic water-expelling precipitants is counseled when right qì is strong and the evil is exuberant, and when water-disinhibiting dampness-percolating medicinals have failed. Some of the drastic water-expelling medicines have a urine-disinhibiting effect so that water-damp is eliminated through not only the stool, but also the urine.

Patterns

Heat constipation (Heat Bind, Yáng Bind)

Pathomechanism: Heat binding in the large intestine, as a result of contraction of external evils, which then enter the interior. It often occurs in yáng brightness (yáng míng ) disease (according to the cold damage system of disease classification) or in exuberant qì-aspect heat patterns of warm disease. It can also result from dietary irregularities such as excessive consumption of liquor or hot spicy foods. In either case, constitutional yáng exuberance may be a factor.

Signs: Dry bound stool, generalized heat effusion, red face, inhibited urination, possibly mouth sores, a red tongue, and in severe cases, tidal heat effusion and delirious speech. The pulse is slippery and rapid or sunken and replete.

Method of Treatment: Clearing heat and precipitating (cold precipitation). The exemplary formula is dà chéng qì tāng (Major Qì-Coordinating Decoction), which contains dà huáng (Rhei Radix et Rhizoma), hòu pò (Magnoliae Officinalis Cortex), zhǐ shí (Aurantii Fructus Immaturus), and máng xiāo (Natrii Sulfas).

Cold constipation (Cold Bind, Yīn Bind)

Pathomechanism: Spleen-kidney yáng vacuity causing yīn cold to congeal and bind. The vacuity may be due to constitutional weakness, dietary irregularities, enduring illness, or natural decline in advancing years. This pathomechanism is often referred to as cold accumulation.

Signs: Cold abdominal pain, abdominal distension, constipation, difficult defecation, lack of warmth in the limbs, cold aching lumbus and knees, long voidings of clear urine, bright white facial complexion, a pale enlarged tongue with white fur, and a pulse that is sunken and slow or fine and forceless.

Treatment method: Warming yáng and freeing the stool (warm precipitation). A classic formula is wēn pí tāng (Spleen-Warming Decoction), in which fù zǐ (Aconiti Radix Lateralis Praeparata), gān jiāng (Zingiberis Rhizoma), dǎng shēn (Codonopsis Radix), and gān cǎo (Glycyrrhizae Radix) are combined with dà huáng (Rhei Radix et Rhizoma).

Large Intestinal Liquid Depletion (Dryness Bind)

Pathomechanism: This disease pattern is caused by a general lack of liquid and blood, which is a consequence of postpartum blood vacuity, liquid depletion in the elderly, or enduring and severe illness. It may also occur in externally contracted febrile disease when heat evil damages liquid.

Signs: Constipation without severe abdominal distension or abdominal pain, and a generally weak state of health. If there is blood vacuity, systemic signs of blood vacuity are usually present.

Method of Treatment: Increasing humor and moistening the intestines (moist precipitation), using intestine-moistening medicinals such as huǒ má rén (Cannabis Semen) and yù lǐ rén (Pruni Semen). Other medicinals that are commonly used in such cases include guā lóu zǐ (Trichosanthis Semen), bǎi zǐ rén (Platycladi Semen), and táo rén (Persicae Semen). The above medicinals may be combined with agents such as xuán shēn (Scrophulariae Radix), mài dōng (Ophiopogonis Radix), ròu cōng róng (Cistanches Herba), and dāng guī (Angelicae Sinensis Radix) to engender liquid and supplement the blood. An exemplary formula is rùn cháng wán (Intestine-Moistening Pill).

Repletion-Pattern Water Swelling (Yáng Water)

Pathomechanism: a) Externally contracted evils invading the body, causing non-diffusion of lung qì and congestion in the triple burner that prevents the free flow of water down to the bladder. b) Damp-heat brewing internally.

Signs: External contractions are characterized by generalized water swelling with heat effusion and aversion to cold, thirst, red facial complexion, fullness and distension in the chest and abdomen, short voidings of reddish urine, and constipation.

Damp-heat brewing internally is characterized by generalized water swelling with heat effusion, thirst, short voidings of reddish urine, and slimy yellow tongue fur. Note that yáng water patterns take many different forms and are treated in different ways. Only severe generalized water swelling is addressed by precipitation.

Method of Treatment: Expelling water and abating swelling, using drastic water-expelling medicinals.

Severe phlegm-rheum Patterns

Pathomechanism: Lung, spleen, and/or kidney disturbances preventing the normal movement and transformation of fluids.

Signs: Rheum collecting in the chest and rib-side (suspended rheum): pain in the chest and rib-side, and cough with copious phlegm. Rheum collecting below the heart (propping rheum): cough, copious phlegm, rapid breathing, inability to lie flat, puffy face, and dizziness.

Method of Treatment: Expel water and drain rheum, using drastic water-expelling medicinals. phlegm-rheum is normally treated by warming and supplementing the spleen and kidney to treat the root, and by disinhibiting water and percolating dampness to treat the tips (see water-disinhibiting dampness-percolating agents). Expelling water and draining rheum is only used as a last resort.

Repletion-Pattern Drum Distention (Ascites)

Pathomechanism: Drum distension arises as a result of qì stagnation and blood stasis, water-damp encumbering the spleen, brewing damp-heat, kidney yáng vacuity, and/or liver-kidney yīn vacuity. More than one of these factors may be operant in any given patient. Precipitation is only applicable where repletion is prominent.

Signs: Severe abdominal distension with somber yellow coloration of the skin, and, in some cases, prominent green-blue veins (caput medusae).

Method of Treatment: Expelling water by offensive precipitation, using drastic water-expelling medicinals combined with other methods depending on the pattern. Medicinals such as gān suì (Kansui Radix), dà jǐ (Euphorbiae seu Knoxiae Radix), yuán huā (Genkwa Flos), qiān niú zǐ (Pharbitidis Semen), bā dòu (Crotonis Fructus), and shāng lù (Phytolaccae Radix) are used. Exemplary formulas include shí zǎo tāng (Ten Jujubes Decoction) and zhōu chē (jū) wán (Boats and Carts Pill).

Other Conditions

Draining-precipitation medicinals are also combined with agents of various categories to treat conditions other than those described above.

For example, large intestinal damp-heat characterized by frequent defecation with pus and blood in the stool, tenesmus, and a burning sensation in the rectum (i.e., dysentery), by fulminant diarrhea, or by diarrhea with ungratifying defecation and foul-smelling stool is treated by clearing heat and disinhibiting dampness, combined with offensive precipitation. For this, dà huáng (Rhei Radix et Rhizoma) or qiān niú zǐ (Pharbitidis Semen) can be combined with qì-moving medicinals such as mù xiāng (Aucklandiae Radix), bīng láng (Arecae Semen), and zhǐ shí (Aurantii Fructus Immaturus).

When food accumulation manifests in abdominal fullness, pain, distension, ungratifying defecation, or tenesmus, draining-precipitants such as dà huáng (Rhei Radix et Rhizoma) may be combined with food-dispersing medicinals if the latter fail to produce satisfactory results on their own.

Wind-phlegm epilepsy with episodes of sudden clouding collapse, foaming at the mouth, and convulsions of the limbs is normally treated by expelling phlegm. In severe cases, draining-precipitant medicinals such as méng shí (Chloriti seu Micae Lapis), dà huáng (Rhei Radix et Rhizoma), and bā dòu (Crotonis Fructus) may be considered. An exemplary formula is méng shí gǔn tán wán (Chlorite/Mica Phlegm-Rolling Pill).

Note on constipation

In addition to heat, cold, and intestinal humor depletion, constipation may also be caused by qì depression or qì vacuity.

• Qì depression constipation: Constipation arising when depressed liver qì affects the spleen and stomach. It is characterized by desire but inability to defecate, belching, pain in the rib-sides and abdomen, thin slimy tongue fur, and a stringlike pulse.
• Qì vacuity constipation: Constipation due to qì vacuity, characterized by lack of power to expel stool and lack of strength after defecation, and accompanied by a bright white facial complexion, a tender-soft tongue with thin fur, and a vacuous pulse.

Combination With Other Categories

• qì stagnation with abdominal distension and pain: Qì-rectifying medicinals can be combined with draining-precipitants to disperse distension and relieve pain, and also to help the stool-freeing action. Draining-precipitants are combined with qì-rectifying agents more commonly than they are combined with any other category of medicinals.
• Heat constipation: Combine with heat-clearing medicinals.
• Cold constipation: Combine with interior-warming medicinals.
• Worm accumulations: Combine with worm-expelling medicinals.
• Damp-heat: Combine with heat-clearing dampness-drying medicinals.
• Interior repletion with vacuity of right qì: Interior repletion can occur in patients suffering from right qì vacuity. In this case draining-precipitant medicinals are combined with supplementing medicinals. This principle of treatment is called simultaneous attack and supplementation. It enables the evil to be attacked without damaging right qì.
• Interior repletion with exterior pattern: When interior repletion coincides with an exterior pattern, it is usual to resolve the exterior first, and then attack the interior. If necessary, draining-precipitants can be used in conjunction with exterior-resolving agents, so that the exterior evil does not fall inward. This is called dual resolution of exterior and interior.

Dosage And Method Of Use

Pill form: Moist precipitants contain oils, making them more suited for use in pill form. Several drastic water-expelling medicinals are also prepared in pill form for treating water swelling and phlegm-rheum, because their water-expelling constituents are not easily soluble in water. In general, some of the strongest agents are used in small pills, while the more gentle offensive precipitants tend to be made into decoctions. Powders or larger honey pills are often used for the mild moist precipitants, though they may be decocted as well.

Toxicity: Drastic water-expelling agents are highly toxic, so they must be used in small quantities. Attention should be paid to reducing their toxicity through processing.

Warnings

Toxic. Offensive precipitants and drastic water-expelling agents are toxic or harsh in nature.

Spleen and stomach: They easily damage right qì and the spleen and stomach.

Strike the disease and stop: Cease medication when the disease is largely eliminated. Extended use is contraindicated.

Protect right qì: Apply the principles of first supplement, then attack and attack and supplement simultaneously.

Elderly and weak: Offensive precipitants and drastic water-expelling agents should be used with care in children, the elderly, those with weak constitutions, and in spleen vacuity.

Women: Many offensive precipitants and drastic water-expelling agents are contraindicated in pregnancy; some are also contraindicated during breastfeeding and during menstruation. Use powerful draining-precipitants in moderation.

Processing: Care should also be taken to ensure that harsh or toxic medicinals are properly processed before use, to prevent poisoning and ensure the safety of the patient.

Habituation: Habitual use of some of these agents can cause dependence, resulting in constipation upon withdrawal. Therefore, in addition to addressing the constipation, it is essential to identify the root cause and not rely solely on the use of offensive precipitants to promote regular bowel movements.