bubble_chart Concept

The tongue appears purple, or purple with a dull and lusterless crimson, or purple with a bluish and smooth texture, all of which are referred to as a purple tongue.

A purple tongue is easily confused with a crimson tongue or a bluish tongue. In ancient medical literature, some believed that a purple tongue is a further development of a crimson tongue; some classified it together with a bluish tongue due to their similar associated diseases; while others distinguished them into two categories, considering bluish as cold and purple as heat.

Based on clinical observations, the formation of a purple tongue can develop from a red crimson tongue into a crimson purple tongue; or it can transform from a pale tongue into a bluish purple tongue with a bluish tint. This indicates that a purple tongue can have different manifestations, either leaning towards crimson or bluish. Due to their different formation mechanisms and clinical significances, they should be distinguished from a simple red crimson tongue or a bluish tongue.

bubble_chart Pattern Analysis

1. Heat Toxin in Blood Aspect︰It is commonly seen in the stage of warm febrile disease with heat invading the blood aspect. The main clinical manifestations include a purple and crimson tongue texture, high fever with dysphoria, or even delirium, macula and papule that are purplish-black, or hematemesis, epistaxis, and a surging and rapid pulse. The purple tongue in $heat toxin in the blood aspect$ differs distinctly from the purple tongue caused by cold pathogens directly attacking, as one is due to heat and the other to cold. In terms of disease cause: The cause of heat toxin in the blood aspect is pathogenic heat, often occurring in warm febrile diseases where unresolved nutrient-level heat allows pathogenic heat to penetrate deeply into the blood aspect, leading to intense heat and toxin accumulation, forcing blood to recklessly move. The purple tongue is a sign of extreme blood heat, as stated in *The Differentiation and Correction of Tongue Diagnosis*: "A fully purple tongue indicates extreme heat in all zang-fu organs." In contrast, the cause of an internal cold pattern is cold pathogens. This condition may arise from constitutional deficiency-cold compounded by exposure to cold, or from mismanagement or mistreatment of cold-damage diseases. As mentioned in *Treatise on Cold Damage*, line 279: "Originally a taiyang disease, but the physician mistakenly applied purgation, leading to abdominal distension and fullness with intermittent pain—this belongs to taiyin..." Cold pathogens directly attacking cause blood stasis and stagnation, as described in *{104|}Suwen．Jutong Lun*: "When cold qi enters the channels, it lingers and stagnates, congealing and failing to circulate..." Hence, the tongue appears purple with a bluish tint. *The Tongue Diagnosis of Cold Damage* states: "A pale purple tongue with blue veins indicates cold pathogens directly attacking the jueyin, a true cold pattern." *The Differentiation and Correction of Tongue Diagnosis* adds: "A pale purple tongue with a bluish hue, lacking coating, moist and thin, signifies cold-damage disease directly attacking the liver and kidney yin." Clinically, the purple tongue in heat toxin in the blood aspect often evolves from a red or crimson tongue. Thus, it appears purple with a crimson hue, possibly with cracks, and a dry, prickly coating, accompanied by symptoms of intense heat and toxin stirring blood (delirium, macula and papule, vomiting blood, or epistaxis). In contrast, the purple tongue in cold-damage disease directly attacking typically develops from a pale tongue, presenting as pale purple with a bluish tint, smooth and moist with little coating, alongside cold signs such as fear of cold, cold limbs, and a slow pulse. Regarding treatment: Both conditions are critical and require urgent intervention. For heat toxin in the blood aspect, as Ye Tian-shi advised: "When entering the blood, beware of blood consumption and reckless movement; cooling blood and dissipating blood stasis must be employed." Treatment should focus on cooling blood to remove toxins, using formulas like Rhinoceros Horn and Rehmannia Decoction or Miraculous Pill of Rhinoceros Horn. For internal cold patterns, the priority is restoring yang to rescue from collapse, using formulas such as Cold-Extremities Decoction or Yang-Restoring Emergency Decoction.
2. Cold Pathogen Directly Attacking︰It is commonly seen in cases where cold-damage disease directly attacks the three yin, with severe internal pudendal coldness. Main clinical manifestations: purple tongue with a bluish tint, shivering of the body, cold limbs, abdominal pain with vomiting and diarrhea, or bluish discoloration of the hands, feet, nails, and lips, deep and slow pulse, or even a deep and faint pulse that barely rises. $Heat toxin in the blood aspect manifests as a purple tongue, while cold pathogen direct attack also presents with a purple tongue! Although both syndromes exhibit a purple tongue, one is heat and the other is cold, distinctly different. From the perspective of disease cause: the cause of heat toxin in the blood aspect is pathogenic heat, often occurring in warm febrile diseases where unresolved nutrient-level heat allows pathogenic heat to penetrate deeply into the blood aspect. The intense heat and toxin force the blood to move recklessly, and the purple tongue is a characteristic of extreme blood heat, as stated in *The Differentiation and Correction of Tongue Diagnosis*: "A purple tongue covering the entire tongue indicates zang-fu organs are all in extreme heat." The cause of internal cold pattern is cold pathogen. This syndrome may form due to inherent deficiency-cold compounded by exposure to cold pathogens, or due to improper or erroneous treatment of cold-damage disease, as mentioned in *Treatise on Cold-Damage Diseases*, Clause 279: "Originally a taiyang disease, the physician mistakenly applied purgation, resulting in abdominal distension and fullness with intermittent pain, which belongs to taiyin..." When cold pathogens directly attack, the meridians and blood stagnate, as described in Suwen.Jutong Lun: "Cold qi enters the meridians and lingers, congealing and failing to move..." Hence, the tongue texture appears purple with a bluish tint. *The Tongue Diagnosis of Cold-Damage Diseases* states: "A pale purple tongue with blue veins indicates cold pathogen directly attacking the jueyin, a true cold pattern." *The Differentiation and Correction of Tongue Diagnosis* adds: "A pale purple tongue with a blue tint, bluish-purple without coating, often moist, smooth, and thin, signifies cold-damage disease directly attacking the liver and kidney yin syndrome." Clinically, the purple tongue in heat toxin in the blood aspect syndrome often develops from a crimson-red tongue. Therefore, the tongue is purple with a crimson hue, possibly with cracks, and the coating is dry and prickly. It is accompanied by symptoms of deep heat and toxin stirring the blood (delirium, macules and papules, vomiting of blood, or nosebleeds). In contrast, the purple tongue in cold-damage disease direct attack syndrome typically evolves from a pale tongue. Thus, the tongue is pale purple with a bluish tint, smooth and moist with little coating, accompanied by cold signs such as fear of cold, cold limbs, and a slow pulse. Regarding treatment: both syndromes are critical and require immediate intervention. For heat toxin in the blood aspect syndrome, as Ye Tian-shi advised: "Entering the blood level risks consuming and agitating the blood; one must cool the blood and dissipate stasis." Treatment should focus on cooling the blood to remove toxins, using formulas such as Rhinoceros Horn and Rehmannia Decoction or Miraculous Pill of Rhinoceros Horn. For internal cold pattern, urgent treatment involves restoring yang to rescue from collapse, using formulas like Cold-Extremities Decoction or Yang-Restoring Emergency Decoction.
3. Static Blood︰Main clinical manifestations: The tongue texture is purple with a grayish hue, dull and lusterless, or there may be masses in the abdomen accompanied by distending pain, primarily characterized by stabbing pain, with fixed and immovable pain locations. The face appears dark and emaciated, with scaly skin, and the pulse is thin and choppy. There are two main causes: 1. Pre-existing static blood, compounded by internal accumulation of pathogenic heat, leading to Jingmai stasis. As Ye Tian-shi stated in *On Warm Diseases*: "When heat transmits to the nutrient-blood level, and the person has pre-existing static blood or old blood stasis in the chest and diaphragm, the heat combines with it, resulting in a tongue color that is purple and dark, moist to the touch." 2. Alternatively, due to emotional stagnation or cold-dampness congealing, the visceral harmony is disrupted, leading to qi and blood stagnation. Over time, this accumulates into masses, and the purple tongue is a sign of internal static blood accumulation. The key diagnostic points are: a purple tongue with a slightly grayish hue, dull and lusterless, accompanied by stasis spots at the edges. The *Tongsu Shanghan Lun* provides a detailed analysis of the symptoms and signs of purple tongue caused by internal static blood accumulation: "A purple tongue color generally indicates liver channel stasis. In cases of heat-induced stasis, the tongue is deep purple and red, either dry or scorched; in cases of cold-induced stasis, the tongue is pale purple with a bluish tint, either dull or slippery." This is worth referencing. The general treatment principle for stasis patterns is invigorating blood and resolving stasis. Prescriptions such as Infradiaphragmatic Stasis-Expelling Decoction or Blood House Stasis-Expelling Decoction may be selected. If masses are present, stasis-resolving and softening-hardness methods are combined. For cases with nutrient-level heat, add ingredients like Moutan Cortex or Unprocessed Rehmannia Root. For accompanying qi stagnation, pair with moving-qi herbs like Lindera or Cyperus.
4. Alcohol Toxin Internal Accumulation︰Commonly seen in patients with alcohol addiction. The main clinical manifestations include: purple tongue texture, swollen tongue body, scorched and dry tongue coating, flushed face and purple lips, bitter taste in the mouth, dry tongue, nausea and vomiting, anorexia, stuffiness and distension in the epigastrium and abdomen, dysuria, and wiry and rapid pulse. Li Dong-yuan Piwei Lun states in the "Treatise on Alcohol-Induced Diseases": "Alcohol is extremely hot and toxic, with both its qi and flavor being yang in nature, and it is an intangible substance." If one becomes addicted to alcohol over a long period or indulges in excessive drinking, alcohol toxins and dampness turbidity accumulate in the body, damaging the spleen and stomach, and in severe cases, alcohol toxins may attack the heart. The "Tongue Mirror" notes: "Alcohol toxins linger in the pericardium and lurk in the meridians and collaterals, preventing qi and blood from nourishing the blood; or drinking ice water after alcohol consumption causes residual alcohol toxins to rush through the meridians and collaterals, with the taste of alcohol entering the heart. Although sweating may occur, there are still residual alcohol toxins in the pericardium, all of which can cause the tongue to appear purple." Clinically, a deep purple, swollen, and dry tongue with scant moisture, a scorched and prickly tongue surface, as well as symptoms of internal obstruction of dampness turbidity in the spleen and stomach (bitter taste in the mouth, nausea and vomiting, stuffiness and oppression in the epigastrium) may be observed. Treatment should focus on clearing heat and detoxifying alcohol, with the prescription selection being Pueraria Flower Sobering-Up Decoction plus Skullcap Root, Coptis Rhizome, etc.

In summary, the symptom of a purple tongue can be categorized into cold, heat, static blood, and alcohol toxicity. It is not difficult to distinguish based on the different manifestations of tongue color and clinical characteristics. Additionally, some patients may exhibit a purple tongue during medical examination due to prolonged and excessive force when extending the tongue, causing tension on the tongue surface, which fades upon retraction. Therefore, when examining tongue color, patients should be instructed to extend their tongue gently and without excessive force to avoid creating a false impression and misdiagnosis.

bubble_chart Documentation

1. 《Tongue Diagnosis Comprehensive Records》: "A purple tongue with a red, swollen, and dry center is caused by residual pathogens after a warm febrile disease, further aggravated by the consumption of alcohol and meat, leading to the accumulation of pathogenic heat. This condition often results in sudden death, indicating internal block and external collapse. In such cases, it is appropriate to use a large dose of Bupleurum to mildly purge. If there is dysphoria with cold extremities and a hidden pulse, first administer Immature Orange Fruit to regulate the middle, followed by a small dose of Minor Qi-Regulating Decoction."
2. 《National Medicine Tongue Inspection Studies》: "A pregnant woman with a purple-blue tongue is caused by the upward surge of heat from the fetal sac. It is advisable to use Coptis Detoxification Decoction. Misuse of medication can endanger both mother and child, as a purple tongue with a bluish tint indicates heat, while a blue tongue with a purple tint indicates cold."
3. 《Guide to Tongue Differentiation》: "If the tongue appears purple and dry, with thirst and dry lips, accompanied by shaoyin pattern, this indicates insufficient kidney yin and a deficiency of water in the kidney. It is appropriate to focus on nourishing water, using formulas such as Six-Ingredient Decoction or Initial Yin Decoction. If accompanied by delirious speech and unconsciousness, treatment should focus on the Hand Shaoyin meridian, mildly clearing phlegm-fire with herbs such as Unprocessed Rehmannia Root, Salvia, Poria, Sichuan Fritillaria, Acorus, Uncaria, and Tabasheer." "Regardless of whether it is a cold-damage disease or a miscellaneous condition, if the tongue color is purple like pig liver, dry, and completely devoid of body fluids, this indicates that the kidney fluids have dried up. If this tongue coating is seen in dysentery, the stomach yin is exhausted, and death is certain."