Issues in the Use of Antiviral Medicinals for the Treatment of Gan Mao by Jason Blalack, M.S., LAc

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There is a growing trend among Chinese herbalists to prescribe medicinals based on their Western function. For example, modern research demonstrates that da qing ye (Isatidis Folium) and ban lan gen (Isatidis/Baphicacanthis Radix) have antiviral properties. Consequently, there are those in both Asia and the West that recommend their use for the treatment and prevention of gan mao (common cold and flu), regardless of the pattern. For example, ban lan gen chong ji (Isatis soluble granulars 板蓝根冲剂),[i] a popular antiviral prepared medicine advertises, “Drinking [sic] a cup of this tea when exposed to others that are sick with a cold or when you think you are coming down with a cold to avoid getting sick yourself.”[ii]

Although such an approach is integrative, innovative, and research based, this article will examine why the use of such medicinals in the treatment and prevention of externally contracted diseases is usually not warranted. Thus, including such medicinals into a formula because of their Western medical function, without understanding the intricacies of how they affect the overall Chinese medicine treatment principles, other medicinals’ actions, and the formula as a whole, can not only lead to an ineffective treatment, but can make the patient’s condition worse and actually injure the patient.

Ban lan gen is probably the most popular antiviral used in gan mao prescriptions. It therefore serves as a good example for analysis, and the issues and concerns around its use can be extrapolated to other similar-natured antiviral medicinals.

The Birth of a New Approach

In the 1950’s Mao Zedong announced his plan for the unification of Western and Chinese medicine. This dramatically changed how Chinese medicine developed, was perceived, and practiced. Although there were already some who were integrating Western medicine ideas prior to this, Mao’s “vision” forced many prominent physicians to research and practice in a Westernized manner.[iii] Consequently, medicinals were increasingly described by their Western attributes. The subsequent treatment strategies that emerged, influenced a whole new generation of doctors and consumers.

Ban lan gen, being one of the most promising “discoveries,” became a key ingredient in popular herbal beverages such as Isatis root herbal drink (ban lan gen liang cha 板蓝根凉茶) and prepared herbal formulas such as ban lan gen chong ji and gan mao ling 感冒灵. Not surprisingly, a great deal of marketing has followed this herb’s growing fame. For example, promotional material for Isatis root herbal drink quotes the Inner Classic, “The sage does not treat an illness that has already [developed], [but instead] prevents disease.” It goes on to say,

“It can prevent disease when there is none. When there is disease it can treat it… It eliminates toxins from the body, boosts the immune system, fights bacterial and viral infections, and balances yin and yang… It clears heat, but does not damage the Spleen and Stomach.”[iv]

Legitimizing an herbal product as one that keeps you healthy as well as treats disease is obviously profitable. Ban lan gen chong ji is even touted as “one of the most popular herbal beverages in China, and a staple in every household.”[v] It is a common belief among Chinese that “it can be used for almost anything, when there is heat.”[vi] Thus at the first sign of a sore throat or common cold, among other conditions, many self-prescribe this.

It is unclear if this popularity is related to true efficacy or marketing. Either way, the above products demonstrate how prevalent ban lan gen is in mainstream Chinese culture and how it and other antiviral medicinals are viewed as seemingly safe and effective for external attacks as well as preventative medicine.

Recently though, there have been many disagreements with this perspective resulting in numerous articles, essays, and case studies illustrating the consequences. Let’s first though examine how this approach relates to Chinese medical theory and what doctors have noticed clinically.

Medical Theory

Western medical theory states that a virus causes the common cold and to treat it we need to destroy the virus. In contrast, Chinese medicine’s approach is to regulate the body’s internal terrain so that the pathogen is expelled. Chinese medicine’s core principle for treating externally contracted diseases is summed up with the Basic Question’s “When a disease is light, scatter it.”[vii] “Light” refers to the exterior and “scatter” refers to the methods of diffusion, discharging, and dispersing. Others, such as Wu Jutong 吴鞠通 have elaborated on this, saying, “One treats the upper burner like a feather. Unless one’s touch is light, one cannot grasp it.” “Like a feather” and light touch refers to using light medicinals such as sang ye (Mori Folium), ju hua (Chrysanthemi Flos), and jing jie (Schizonepetae Herba). Therefore, for externally contracted wind diseases one should use medicinals that are balanced, smooth, light, and are quick to guide the wind pathogen from the protective aspect to the outside of the body.

Using antiviral medicinals is often at direct odds with Chinese medicine’s fundamental theory. For example, ban lan gen’s nature is bitter, cold, and heavy and it primarily directs downward. It is indicated for more serious presentations that usually involve internal heat. China’s Materia Medica (中华本草 zhong hua ben cao) describes ban lan gen this way:

“It enters the Liver and Stomach channels, clears heat, resolves toxicity, cools the blood and unhinders the throat. It is indicated for warm toxin macular eruption, high fever with headache, massive head scourge epidemic, dark purple-red tongue, putrefying throat cinnabar sand, cinnabar toxin, mumps, painful obstruction of the throat, swelling of sores, chicken pox, measles, hepatitis, influenza, epidemic cerebrospinal meningitis, pneumonia, unconsciousness, swollen throat, and fire eye.”

Quite simply, according to Chinese medicine theory, ban lan gen is contraindicated for wind attacks, wind-cold attacks, and most early-stage wind-heat attacks.[viii] When used in these situations, ban lan gen's downward nature can drive the pathogen deeper and its cold nature can not only congeal a cold pathogen, but can also turn a heat pathogen into a cold pathogen, essentially freezing it. This is very similar to what happens when antibiotics are given incorrectly.

Clinical Evidence

In the Qing dynasty, epidemics were devastating families and external pathogenic theory became a focal point for many physicians. Quite simply, if doctors could eliminate a pathogen or keep it from entering, they could save a life. The innovative physicians from this time developed new effective treatment strategies, many of which became part of the warm disease (wen bing)  current.

However, according to doctors’ case records and writings, they did not use ban lan gen, or similar medicinals, in early stage gan mao.[ix] Although they certainty discussed these medicinals in relation to other (deeper) conditions, they still favored a light, scattering, and diffusing method when treating externally contracted diseases. The obvious question is, if ban lan gen is so effective now, why did these doctors not use it back then?

Doctors from the Qing dynasty to present have articulated concerns around these bitter cold medicinals to help us answer this question. Li, in his Discussion of Misdiagnosis in Chinese medicine, describes the fundamental issue of giving bitter cold medicinals in an exterior pattern, which results in “the [exterior] pathogen becoming constrained in the interior (108-109).” This core pathodynamic is synonymous with what many call lurking pathogens.

Even giving cold medicinals when there is a heat condition can bring about injury. This is especially a concern if there is internal or external dampness. For example, Zhang Xichun (1860-1933), one of the most prominent physicians of the 19-20th centuries, in Essays on Medicine Esteeming the Chinese and Respecting the Western elaborates on this. He discussed how giving cold medicinals can create wheezing in a summerheat condition when there is no previous wheezing (406). Zhao Shaoqin (1918-2001), the famous warm disease expert, has two cases of interest. The first is entitled Lurking Ice where the etiology of a mistreated case is described, “This was a [pattern of] summerheat-damp brewing heat, in which excessive cold medicinals were taken. This covered the pathogen [creating] lurking ice in the middle burner (24).” This case is preceded by a summerheat condition that turned to congealed cold by merely eating cold food and drinks (23). Thus, if cold foods can cause a problem, we must be extra careful with bitter cold medicinals.

Because of its overuse, ban lan gen’s inappropriateness is nowadays often discussed. As a result, we find many mainstream articles in Chinese openly criticizing this approach. For example there is, Ban lan gen is not an all-purpose medicinal, is it able to treat the common cold?,[x] To use ban lan gen one must differentiate disease[xi] and Ban lan gen is unable to guard against the gan mao.[xii] Another article discusses its dangers:

“If [ban lan gen] is used to treat wind-cold gan mao, not only will it be ineffective, but it also worsens the gan mao and damages the body. If one just reflexively uses ban lan gen for the incubation periods of gan mao [preventative treatment], it may have an effect, may not, or may even cause more problems… ban lan gen’s nature is cold and bitter and can easily can damage the Spleen and Stomach. Therefore it is unsuitable to use ban lan gen in patients with Spleen and Stomach deficiency cold patterns (e.g. low appetite or an uncomfortable feeling after eating something cold). Its use can bring about a serious illness, due to the draining of ‘correct qi’. This is especially true in children where their digestive system is not yet fully developed.”[xiii]

We also find case records specifically documenting the consequences of ban lan gen.

Chen presents a case of a 45-year-old patient that contracted a typical gan mao with fever and chills and body aches. He self-prescribed antiviral patent medicines, ban lan gen chong ji and gan mao qing 感冒清.[xiv] Although this relieved his fever and chills, it drove the pathogen deeper into the shao yang, resulting in a serious presentation with essence spirit deterioration, dizziness, etc. Xiao chai hu tang (Minor Bupleurum Decoction) was given and cured him (344).

Another article by Blalack, Chace, and Schaefer (2007), presents a case study that documents how a lurking pathogen was created by simply adding ban lan gen and da qing ye to a typical venting gan mao formula. Thus, even a formula that contains many venting medicinals can be weighed down by this class of cold and bitter medicinals, preventing proper eviction of the pathogen.

In our clinic we have seen quite a few complications from these antiviral formulas, such as gan mao ling and other Western gan mao patent formulas, especially when taken at the first signs of a “cold”.  One difficulty in evaluating outcomes is that initial symptoms often quickly resolve from taking cold- bitter antiviral medicinals, giving the impression of therapeutic success. However, symptoms often return after a few days or even weeks, or the pathogen transmutes into another problem, such as a urinary tract infection. Even worse, a deeper lurking pathogen may be created that will cause problems for time to come. Thus, such incidents are often overlooked because of insufficient patient follow-up or not knowing what to look for.

Western research

A complete evaluation of the issues related to Western style research on medicinals, especially in China, is beyond the scope of this paper. However I would like to bring up one clinical point. Sometimes merely defining a medicinal as antiviral is too simplistic. If we want to play the Western medicine game we are destined to run into similar problems as they do. For example, there are many pathogens that give rise to upper respiratory tract infections such as mycoplasmal pneumonia, pneumococcus, chlamydia pneumoniae, and legionella pneumonia. Although ban lan gen has a clear antiviral function, it actually has a pretty poor effect against pathogens such as mycoplasmal pneumonia and chlamydia pneumoniae type infections.[xv] Therefore, if one is unable to determine the specific pathogen of the gan mao and indiscriminately uses this medicinal, one may not obtain the desired effect. The bigger question is, what does it mean to be antiviral? Even herbs commonly used as food, such as chen pi (Citri reticulatae Pericarpium), when tested in a laboratory are said to be antiviral! How does this data though translate into clinical reality? Furthermore, one might ask, how successful has the Western medicine model been at treating the common cold? They certainly have a large arsenal of antiviral drugs.


There are many that advocate using antiviral medicinals at the first sign of gan mao, regardless of the pattern, pathogen, or patient’s constitution. Some go as far as suggesting that one should use such medicinals as preventative medicine. I have found no clinical evidence, nor support in the literature to support this approach.

I do think though, there are times that ban lan gen, and other clear heat and toxin medicinals, should be used in cases of gan mao. Such decisions though should be based on a Chinese medicine perspective, respecting the centuries of wisdom that we have to guide us. That is, one should consider the pattern’s nature (e.g. is there internal heat?), its severity, the location and nature of the pathogen, and the patient’s constitution. Consequently the vast majority of externally contracted conditions do not warrant the use of antiviral medicinals such as ban lan gen.


1.     Anonymous (compiled by: 王洪图). Huangdi neijing suwen 黄帝内经素问 (Yellow Emperor’s Inner Classic: Basic Questions). Beijing: Renmingweisheng chubanshe 人民卫生出版社, 2000.

2.     Blalack, J., Chace, C. & Shaefer, J. 2007. “Lurking pathogens: three modern case studies.” The Lantern, Vol 4(2), 4(3). It can be viewed at:

3.     Chen Ming 陈明, and Zhang Yinsheng 张印生. Shanghan mingyi yanan jingxuan 伤寒名医验案精选 (Hand selected cold damage cases from famous doctors). Beijing: Xueyuan chubanshe 学苑出版社, 1998.

4.     Li Candong 李灿东. Zhongyi wuzhen xue 中医误诊学 (Discussion of Misdiagnosis in Chinese medicine). Fujian kexuejishu chubanshe 福建科学技术出版社. 2003.

5.     Peng Jianzhong 彭建中 and Yang Lianzhu 杨连柱.  Zhao Shaoqin yan an jing xuan 赵绍琴验案精选 (An Essential selection of Zhao Shaoqin’s Clinically Verified Case Records) Beijing:  Xueyuan chubanshe 学苑出版社. 1996.

6.     Taylor, Kim. Chinese Medicine in Early Communist China, 1945-1963: A Medicine of Revolution (Needham Research Institute Series). Routledge, 2005.

7.     Wu Jutong 吴鞠通. Wenbing tiaobian 温病条辨 (Systematic Differentiation of Warm Pathogen Diseases), 1798. Beijing: Renmingweisheng chubanshe 人民卫生出版社, 1963

8.     Zhang Xichun 张锡纯. Essays on Medicine Esteeming the Chinese and Respecting the Western (医学衷中参西录 yixue zhongzhong canxi lu), 1913. Hebei: Hebei kexuejizhu chubanshe 河北科学技术出版社, 2002 p.406

[i]  Contains ban lan gen.

[iii] See Taylor, Kim.

[iv] ibid

[vi] Personal conversation with Chu Xingyan June 2011.

[vii] Basic Questions: Comprehensive Discussion on the Phenomena Corresponding to Yin and Ying (su wen, yin yang ying xiang da lun 素问, 阴阳应象大论).

[viii] Of note, when people first are “catching a cold” they usually have a wind attack, not a full-blown wind-heat or wind-cold pattern.

[ix] This is based on my review of around 25 pre-modern case record books as well an internet search in Chinese.

[x] 板蓝根不是万 能药能不能治感冒 (10-21-2009). Original Source: Zhongguo zhongyi yaobao 中国中医药报,.

[xi] 应用板蓝根必须辨证 (1-18-2010). China’s Chinese Medicine Newspaper (中国中医药报) China’s

[xii] 板蓝根不能预防感冒

[xiii] The importance of paying attention to the pathomanifestation when drinking ban lan gen to prevent gan mao (he banlangen yufang ganmao yao duizheng 喝板蓝根预防感冒要对症),

[xiv] Helicteris Herba (shan zhi ma) , Isatidis/Baphicacanthis Radix (ban lan gen) , Bidentis Bipinnatae Herba (gui zhen cao) , Ilicis Asprellae Radix (gang mei gen), Isatidis Folium (da qing ye), and Andrographitis Herba (chuan xin lian). 

[xv] Is drinking ban lan gen effective for gan mao? (ganmao le he banlangen guanyong ma? 感冒了喝板蓝根管用吗?) (12/22/2008).
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