Introduction: The author of this article believes that psoriasis is often caused by the obstruction of meridians by wind, cold, and damp pathogenic factors, leading to malnutrition of the skin. This perspective offers a new direction for the treatment of psoriasis.

Treating Psoriasis from the Perspective of Bi Syndrome

Jiang Wei

Psoriasis is a common clinical disease in dermatology, easy to diagnose but quite challenging to treat. Modern medicine has not yet fully elucidated its etiology and pathology. Traditional Chinese medicine's "dry tinea," "pine bark tinea," and "white scale" are similar to it. "Surgical Compendium" states: "White scale: the skin is like papules and scabies, white in color and itchy, scratching produces white scales, commonly called snake wind. It is caused by wind pathogens lodging in the skin, and blood dryness failing to nourish it." Its etiology is often attributed to "wind pathogens," "blood dryness," and "blood heat," and treatment also often focuses on these aspects. Based on years of exploration, the author believes that the three pathogens—wind, cold, and dampness—are the main pathogenic factors, with dryness being the external manifestation. This is because the three pathogens—wind, cold, and dampness—block the meridians and collaterals, causing stagnation of qi and blood, leading to the skin losing nourishment and manifesting symptoms of dryness and scaling. Treatment often focuses on dispersing wind and resolving dampness. A preliminary analysis is as follows.

I. Theoretical Basis

"The Inner Canon of the Yellow Emperor: Treatise on Impediment" states: "When wind, cold, and dampness combine, they form impediment... encountering this in autumn is called skin impediment." It also states: "What is called impediment is each [type] occurring when [the body] is heavily affected by wind, cold, and dampness at its respective time." Literally, "impediment" means blockage, that is, a series of diseases formed by the blockage of meridians and collaterals by the three pathogens—wind, cold, and dampness. The treatise mentions the disease name "skin impediment," discussing that its onset season is autumn, but it does not elaborate on its symptoms. Regarding the symptoms manifested by impediment syndromes, it states: "Impediment may cause pain or blockage... or dryness or dampness, what is the reason for this?" However, it later lacks discussion on the pathological mechanism of dryness caused by impediment. Based on the fact that psoriasis often occurs in autumn and is characterized by dry, scaling skin, the author believes that "skin impediment" shares certain similarities with psoriasis.

Psoriasis lesions occur without a fixed location, and the disease course is prolonged and difficult to cure, which also aligns with the pathogenic characteristics of wind, cold, and dampness. Wind is the leader of all diseases, characterized by its tendency to move and change rapidly, which explains why the rashes appear without a fixed location, with some subsiding while others emerge. Wind pathogens often combine with cold and dampness when attacking the body. Cold causes contraction, and when cold pathogens constrict the surface, the meridians contract, leading to stagnation of qi and blood, and the skin loses its nourishment, resulting in dryness, itching, and abundant white scales. Dampness is heavy, turbid, sticky, and difficult to resolve, which is why the disease course is prolonged and prone to recurrent episodes.

Modern medicine classifies psoriasis into four types: plaque psoriasis, psoriatic arthritis, pustular psoriasis, and erythrodermic psoriasis. The progression among these types can also be explained through the three pathogenic factors of wind, cold, and dampness. When wind, cold, and dampness invade the skin, they obstruct the flow of qi and blood, leading to malnutrition of the skin or prolonged stagnation that transforms into heat and dryness, resulting in plaque psoriasis. If the condition persists without improvement, or if the body's vital energy is deficient while pathogenic factors are excessive, wind, cold, and dampness may travel to the meridians and collaterals, causing joint swelling and pain characteristic of psoriatic arthritis. When cold and dampness transform into heat, and damp-heat accumulates to generate toxins, pustular psoriasis develops. As all six climatic factors can transform into fire, prolonged stagnation of damp-heat may generate fire and wind, leading to erythrodermic psoriasis.

II. Syndrome Differentiation and Treatment

1. Wind-Cold-Dampness Type: This pattern corresponds to psoriasis vulgaris, often occurring in autumn and winter, with a short disease course. The rash is mostly drop-like, few in number, and develops slowly. The rash color is pale red. In the early stage, it may be accompanied by lung-defense exterior syndrome. The tongue is red with thin white coating, and the pulse is floating. All these are the key points for pattern differentiation of this type, which is caused by wind-cold-dampness binding the exterior, obstructing the nutrient and defense systems, and impairing the meridians. The treatment principle is to release the exterior, disperse cold, and resolve dampness. The formula selected is Modified Ephedra Decoction with Atractylodes, with medicinal ingredients including honey-fried ephedra, cinnamon twig, apricot kernel, atractylodes rhizome, white atractylodes rhizome, raw coix seed, large-leaved gentian root, smilax glabra rhizome, and licorice root. In the formula, honey-fried ephedra and cinnamon twig promote sweating to release the exterior and disperse cold; apricot kernel assists in diffusing the lung; atractylodes rhizome, white atractylodes rhizome, raw coix seed, smilax glabra rhizome, and large-leaved gentian root dispel cold-dampness in the exterior. Meanwhile, white atractylodes rhizome is used to restrain ephedra to prevent excessive sweating, and licorice root harmonizes all the ingredients.

2. Wind-Damp-Heat Pattern: This pattern corresponds to the progressive stage of psoriasis, characterized by rapid spread of rashes over the entire body, bright red color, abundant scaling, isomorphic reaction phenomenon, severe itching, red tongue with thin and slightly yellow coating, and rapid pulse. This is also the key to pattern differentiation for this type. The three pathogenic factors of wind, cold, and dampness contend in the skin, while healthy qi remains, preventing the pathogens from transmitting inward along the channels. Prolonged stagnation transforms into heat, and the heat assists the pathogenic force, leading to rapid dissemination of rashes with bright red color and abundant scaling. Although the pathogens have transformed into heat, they still linger in the exterior. Treatment should aim to diffuse the lung and release the exterior, clear heat, and resolve dampness. The modified formula of Mahuang Lianqiao Chixiaodou Tang (Ephedra, Forsythia, and Red Bean Decoction) is selected. Mahuang Lianqiao Chixiaodou Tang is a classic formula for treating yang jaundice with exterior syndrome. Using this formula to treat wind-damp-heat pattern psoriasis aims to disperse wind pathogens in the exterior with acrid-dispersing herbs like Mahuang (Ephedra) and Xingren (Apricot Kernel), clear and drain damp-heat with Lianqiao (Forsythia), Sangbaipi (Mulberry Root Bark), and Chixiaodou (Red Bean), harmonize the spleen and stomach with Dazao (Jujube) and Gancao (Licorice Root), and add Jingjie (Schizonepeta), Fangfeng (Saposhnikovia), Baizhu (Atractylodes), and Tufuling (Smilax) to dispel dampness in the exterior. For severe heat pathogens, add Shigao (Gypsum) to clear and drain internal heat. All herbs together achieve the effect of diffusing the lung and releasing the exterior, clearing heat, and resolving dampness.

3. Pathogen Obstructing the Channels and Collaterals Pattern: This pattern corresponds to psoriatic arthritis. The key points of pattern differentiation are the presence of typical psoriatic skin lesions accompanied by joint swelling, pain, limited movement, or even stiffness, deformity, and inability to straighten when bent, pale tongue with thin, white, and slightly greasy coating, and wiry or soggy pulse. This is due to prolonged illness with improper treatment or deficiency of healthy qi and excess of pathogens, allowing wind, cold, and dampness to enter the channels and collaterals along the channels. Treatment should aim to dispel wind, eliminate dampness, activate blood, and unblock the collaterals. Modified Duhuo Jisheng Tang (Pubescent Angelica and Mistletoe Decoction) is used. Medicinals include Qianghuo (Notopterygium), Duhuo (Pubescent Angelica), Sangjisheng (Mistletoe), Qinjiao (Gentiana), Fangfeng (Saposhnikovia), Guizhi (Cinnamon Twig), processed Chuanwu (Aconite), Niuxi (Achyranthes), Danggui (Chinese Angelica), Chuanxiong (Ligusticum), Tufuling (Smilax), etc. For deficiency of healthy qi unable to overcome pathogens, add Huangqi (Astragalus) and Dangshen (Codonopsis).

4. Damp-Heat Accumulating Toxin Pattern: This pattern corresponds to pustular psoriasis. Clinical manifestations include psoriatic rashes accompanied by numerous superficial, aseptic pustules of varying sizes. Lesions commonly occur on the palms and soles but can also spread over the entire body. Severe cases may be accompanied by systemic symptoms such as fever, thirst, dark urine, and constipation. Tongue is red with yellow coating, and pulse is slippery and rapid. Wind, cold, and dampness pathogens obstruct the skin, transforming into heat and generating toxin over time. Treatment should aim to clear heat, resolve dampness, and detoxify. Modified Huanglian Jiedu Tang (Coptis Decoction to Relieve Toxicity) combined with Wushen Tang (Five Spirits Decoction) is used. Medicinals include Huanglian (Coptis), Huangqin (Scutellaria), Huangbai (Phellodendron), Tufuling (Smilax), Yinhua (Honeysuckle), Zihuadiding (Viola), Qiyeyizhihua (Paris), raw Yiyiren (Coix), Cheqianzi (Plantago), etc.

5. Damp-Heat Transforming into Fire Pattern: This pattern corresponds to erythrodermic psoriasis. The key points of pattern differentiation are diffuse erythema, burning heat, and leaf-like scaling over the entire body, accompanied by varying degrees of fever, restlessness, thirst, dark urine, and constipation. Tongue is deep red with scant coating, and pulse is slippery and rapid. It is due to damp-heat stagnating for a long time, transforming into fire and generating wind. Treatment should aim to clear heat and detoxify, cool blood, and nourish the nutrient aspect. Modified Xijiao Dihuang Tang (Rhinoceros Horn and Rehmannia Decoction) is used. Medicinals include Shuiniujiao (Water Buffalo Horn), Daimao (Hawksbill Turtle Shell), Xuanshen (Scrophularia), Shengdi (Rehmannia), Shashen (Glehnia), Yinhua (Honeysuckle), Danzhuye (Lophatherum), Shanzhi (Gardenia), Huangqin (Scutellaria), Huanglian (Coptis), etc.

III. Case Examples

Yin, female, 26 years old. Initial consultation on November 28, 1992. Presented with red patches on the limbs and mild itching for 15 days. History of a cold before onset, which was cured with unspecified medication. Shortly after recovery, two erythematous patches appeared on the lower limbs with scaling and mild itching, but no treatment was sought. Recently, similar lesions appeared on the upper limbs, prompting a visit to our outpatient department. Examination: Scattered infiltrative erythematous patches on the extensor surfaces of the limbs, light red in color, well-defined borders, covered with white scales, with a thin film phenomenon and punctate bleeding. No skin lesions were observed on the trunk or head. Tongue: red with thin white coating. Pulse: floating. Syndrome differentiation: Wind-cold-dampness binding the exterior, disharmony of nutrient and defense qi, obstruction of meridians, and loss of nourishment to the skin. Treatment method: Disperse wind, dissipate cold, and eliminate dampness. Modified Mahuang Jia Zhu Decoction: Prepared Ephedra (Zhi Mahuang) 5g, Cinnamon Twig (Guizhi) 5g, Coix Seed (Sheng Yiyiren) 30g, Smilax Glabra Rhizome (Tufuling) 30g, Sophora Flower (Sheng Huaihua) 30g, Apricot Kernel (Xingren) 10g, White Atractylodes Rhizome (Baizhu) 10g, Atractylodes Rhizome (Cangzhu) 10g, Honeycomb (Fengfang) 10g, Clematis Root (Weilingxian) 10g, Licorice Root (Fencao) 6g. After 5 doses, the rash color lightened and scaling decreased. As the formula was effective, it was continued for another 10 doses, after which the rash completely subsided, leaving mild hypopigmented patches. No recurrence was reported during a three-year follow-up.

Chen, male, 41 years old. Initial consultation on June 27, 1995. Presented with widespread rash and severe itching for over a month. History of psoriasis for over three years, previously treated with various unspecified medications without cure. Due to few lesions and mild symptoms, treatment was discontinued. Since June, the rash rapidly increased with intense itching, leading to a visit to our outpatient department. Examination: Multiple bright red infiltrative erythematous patches all over the body, well-defined borders, covered with multiple layers of silvery-white scales, with a thin film phenomenon and punctate bleeding. Scratch marks were widespread, with linear lesions visible. Similar lesions were present on the head, with hair in tufts. Tongue: red with thin yellow coating. Pulse: rapid. Syndrome differentiation: Wind-cold-dampness trapping the exterior, stagnating and transforming into heat and fire. Treatment method: Diffuse the lung and release the exterior, clear heat, and transform dampness. Modified Mahuang Lianqiao Chixiaodou Decoction: Ephedra (Mahuang) 5g, Scorpion (Quanxie) 5g, Apricot Kernel (Xingren) 10g, Forsythia Fruit (Lianqiao) 10g, Mulberry Root Bark (Sangbaipi) 10g, Phaseolus Calcaratus (Chixiaodou) 10g, Schizonepeta Herb (Jingjie) 10g, White Atractylodes Rhizome (Baizhu) 10g, Liuyi Powder (Liuyi San, wrapped) 10g, Gypsum Fibrosum (Sheng Shigao, added later) 20g, Smilax Glabra Rhizome (Tufuling) 30g, Coix Seed (Sheng Yiyiren) 30g. After 5 doses, itching decreased and rash color lightened. After another 10 doses, itching resolved completely, and rash on the trunk and upper limbs subsided entirely, but some lesions remained on the lower limbs. Dampness is heavy and turbid; this indicates residual dampness. Therefore, Gypsum Fibrosum was removed from the original formula, and Large-leaf Gentian Root (Qinjiao) 10g and Pubescent Angelica Root (Duhuo) 10g were added. After another 10 doses, the rash completely subsided. No recurrence was reported during a one-year follow-up, after which contact was lost.