Skip to main content
bei wuweizi ©Erich Stöger
daihuang ©Erich Stöger
danggui ©Erich Stöger
danzhuye ©Erich Stöger
difuzi ©Erich Stöger
gualouzi ©Erich Stöger
hehuanhua ©Erich Stöger
xiangfu ©Erich Stöger

Pinelliae Rhizoma, ban xia

Pinelliae Rhizoma (ban xia) plays an important role in Chinese medicine. The unprocessed herb is classified as toxic; therefore, only the processed form may be used for internal admi­ni­stration. This raises the question of whether the properly processed herbal medicine, Pinelliae Rhizoma Praeparatum (zhi ban xia), also poses a risk when administered internally.

Unprocessed Pinelliae Rhizoma (sheng ban xia)

Unprocessed Pinelliae Rhizoma (sheng ban xia) can cause intoxication at doses as low as 0.1–0.8 g. Symptoms develop within 30 minutes to 2 hours after ingestion and include a burning sensation in the mouth, numbness and swelling of the mouth and tongue, mucosal erosions, salivation, difficulty opening the mouth, a sensation of dryness in the throat, hoarseness, laryngospasm, dysphagia, vomiting, and diarrhea. Ingestion of an excessive dose could lead to hepatic and renal injury, along with neurological manifestations such as dizziness and limb paresis, potentially progressing to coma and respiratory arrest, which may result in death by asphyxiation. In children, the herb may impair intellectual development and cause irrever­sible neurological damage [1, 2]. Potential cardiotoxic effects include palpitations, cardiac arrhythmias (tachycardia, nodal escape rhythm, atrial flutter, and atrial fibrillation), and heart failure [3].

The mucosal irritant effects of the herb are attributed to the sharp calcium oxalate crystals it contains. A study of Pinelliae Rhizoma Praeparatum cum Zingibere et Alumine (Jiang Ban Xia) demonstrated that processing does not reduce the calcium oxalate content but does cause the sharp needle-shaped crystals to aggregate into bundles containing blunter needles [4]. The constituents responsible for the full spectrum of toxic effects have not yet been adequa­tely elucidated.

Processed Pinelliae Rhizoma (zhi ban xia)

The three main processing methods are as follows:

  • Pinelliae Rhizoma Praeparatum (fa ban xia): This is the standard processing method. The herb is soaked for several days in a solution of licorice and lime at a pH above 12. Fa ban xia is particularly effective in addressing cold-phlegm and dampness-phlegm.
  • Pinelliae Rhizoma Praeparatum cum Zingibere et Alumine (jiang ban xia): In this method, the herb is boiled in a solution containing ginger and Alumen (bai fan). Jiang ban xia acts primarily on the middle burner, transforms phlegm, directs rebellious qi downward, and alleviates vomiting.
  • Pinelliae Rhizoma Praeparatum cum Alumine (qing ban xia): This preparation is produced by boiling the herb in an 8% Alumen solution or by soaking it for an extended period. Qing ban xia primarily dries dampness and transforms phlegm [5].

Case Reports

How should the tolerability of processed Pinelliae Rhizoma (zhi ban xia) be assessed? While numerous case reports from China describe poisoning caused by the unprocessed herb, some involving high doses, we identified only three case reports from China involving pro­cessed or purportedly processed Pinelliae Rhizoma.

In the first case, a 45-year-old woman, herself a physician, took 15 g of ‘zhi ban xia’ as part of a modified combination of the formulas xiang sha ping wei san and er chen tang. The follo­wing day, she experienced itching, swelling, and pain in the throat, a burning sensation, and hoarseness. Her pre-existing epigastric discomfort worsened, and she developed loss of appetite and nausea. The pharmacy confirmed the authenticity of the herbal medicines. Subsequent analysis provided evidence suggesting that the herb had been inadequately processed: A test solution prepared from the outer layer of the herb caused no symptoms, whereas a solution prepared from the inner layer did [6]. Furthermore, the standard dosage range for zhi ban xia (3–9 g) had been exceeded.

In another case, a 63-year-old woman took a decoction containing fa ban xia 9 g, zhi ma huang 9 g, gui zhi 9 g, xi xin 3 g, wu wei zi 10 g, chuan bei mu 10 g, zi su zi 20 g, bai jie zi 20 g, and jie geng 10 g. Two hours after taking the first dose, she developed muscle twitching in the extremities, hallucinations, agitation, and delirium. Upon admission to hospital a further six hours later, she was comatose and delirious, with a pulse rate of 124 beats/min, persis­tent muscle twitching, pathologically exaggerated reflexes, and moist crackles on lung aus­cultation. One hour later, she regained consciousness, and the muscle twitching subsided [7]. In this case, the doses of Sinapis Semen (bai jie zi; standard dose 3–9 g) and Perillae Fructus (zi su zi; standard dose 3–10 g) were excessive. The report provides no information on whe­ther the patient had taken any other medications, including conventional pharmaceu­ti­cals.

In the third case, a 39-year-old woman had ingested more than 20 packets of qing ban xia, each containing 2 g. On admission to hospital, she was deeply comatose, with pinpoint pupils that reacted sluggishly to light, a blood pressure of 175/85 mmHg, reduced muscle tone, and diminished reflexes. She was successfully treated with gastric lavage, venovenous hemofiltra­tion, and hemoperfusion [8]. The report provides no explanation for how she came to ingest more than 40 g of qing ban xia, but it can be assumed that this was not the result of a medi­cal prescription.

Case 1 involved relatively mild symptoms following an overdose of apparently inadequately processed Pinelliae Rhizoma. It does not indicate a risk associated with properly processed zhi ban xia when used within the recommended dosage range. Case 3 clearly involved an excessive overdose and likewise provides no basis for inferring a risk under normal condi­tions.

This leaves case 2, which involved reportedly processed Pinelliae Rhizoma (fa ban xia) at a dose that remained within the standard dosage range. Since this is the only case report we could identify under these conditions, and given the severity of the symptoms, the adequacy of processing must be questioned, particularly since no verification of proper processing was performed. The symptoms are not entirely typical of those reported following exposure to unprocessed Pinelliae Rhizoma. Whether the excessive doses of two other herbal medicines contributed to the clinical presentation could not be determined.

The CTCA has received no reports of suspected adverse drug reactions in which Pinelliae Rhizo­­ma may have played a causal role, nor has the CTCA become aware of any such cases in Europe.

Potential Incompatibilities

According to the traditional rule of the 18 Incompatibilities, Pinellia is incompatible with all Aconitum herbal medicines. The validity of this potential interaction risk has been widely debated [9]. Many renowned physicians, including Zhang Zhongjing, Li Shizhen, and Sun Simiao, described formulas combining fu zi(Aconiti Radix Lateralis Praeparata) with ban xia. This combination is also used relatively frequently in modern clinical practice [9].

We identified three case reports describing intoxication associated with the concomitant use of Pinelliae Rhizoma and Aconitum medicines. In one case, a decoction was administered that contained, among other ingredients, 8 g of zhi ban xia, 10 g of zhi chuan wu (Aconiti Radix Praeparata), 5 g of zhi cao wu (Aconiti Kusnezoffii Radix Praeparata), and 8 g of chuan bei mu (Fritillariae Cirrhosae Bulbus). Fritillariae Cirrhosae Bulbus is traditionally also con­sidered incompatible with Aconitum medicines. One and a half hours after taking the first dose, a 44-year-old man developed severe signs of intoxication, including dyspnea, limb spasms, paralysis, and impaired consciousness [10]. As both Aconitum medicines were administered at substantially excessive doses, this case can hardly be cited as evidence of an interaction risk under normal conditions. The neurological symptoms are more consistent with intoxication caused by unprocessed Pinellia than with Aconitum overdose. It is therefore worth considering whether the Pinellia used had been adequately processed and whether its effects may have been further exacerbated by Aconitum. Since proper processing cannot be verified, this question remains unresolved.

In another case, 6 g of qing ban xia was administered together with 6 g each of Aconiti Radix Praeparata and Aconiti Kusnezoffii Radix Praeparata. Within just 10 minutes, a 35-year-old woman developed signs of intoxication characteristic of Aconitum poisoning, including atrial fibrillation and circulatory shock [11]. As the Aconitum herbal medicines were administered at substantially excessive doses, the outcome can be explained without invoking a drug inte­raction.

In the third case, a 30-year-old patient took a decoction containing 10 g of ban xia and 10 g of fu zi (Aconiti Radix Lateralis Praeparata). Signs of intoxication characteristic of Aconitum poisoning developed, including bradycardia and a nodal escape rhythm [12]. In this case, no information was provided regarding whether the ban xia had been processed. Consequently, this report does not provide reliable evidence of an interaction involving processed ban xia.

Studies on Interactions

Zhang Ling et al. conducted a study on mice to investigate the extent to which the acute toxicity of an ethanol extract of unprocessed Aconiti Kusnezoffii Radix was affected by ethanol extracts of fa ban xia, Trichosanthis Fructus (gua lou), and Bletillae Rhizoma (bai ji). While the toxicity increased following administration of the Trichosanthes and Bletilla extracts, it decreased with increasing doses of the fa ban xia extract [13]. Other animal studies reported increased toxicity with the combination of Aconitum and Pinellia [9, 14], whereas an in vitro study suggested an increase in toxicity only with unprocessed Pinelliae Rhizoma [15].

A more recent review identified 1,588 clinical studies or case series in which Aconitum and Pinellia appeared together in herbal formulas. Only 79 provided specific information on adverse effects. Pinellia and fu zi were the most frequently co-administered substances, at doses of 10 g and 15 g, respectively, although doses of up to 30 g of each substance were also reported. Gastrointestinal adverse effects were reported most frequently, whereas cardiac symptoms were uncommon; in particular, no cardiac arrhythmias were reported. Neurological effects of non-severe intensity were reported more frequently. Overall, the information provided in these studies was too imprecise or incomplete to permit reliable conclusions regarding the safety of the Aconitum–Pinellia combination, particularly because the other ingredients in the formulas would also need to be considered when evaluating the reported adverse effects [16].

Conclusion

Provided that the medicinal substance meets appropriate quality standards and is admi­nistered at the recommended dosage, serious adverse effects from Pinelliae Rhizoma Praeparatum (zhi ban xia) are not expected. However, allergic reactions and mild gastroin­testinal complaints may occur [17]. The standard dosage of 3–9 g should be strictly adhered to and appropriately reduced in children, older adults, and debilitated patients. Pinelliae Rhizoma Praeparatum is contraindicated during pregnancy [18]. The herbal medi­cine should be obtained from a reputable supplier. Although the combination with Aconitum medicines are unlikely to pose an increased safety risk, a cautious dosing regimen should nevertheless be adopted as a precaution.

References

  1. Yu TT, Li WP and Ding ZS. [Understanding the application and toxicity of Pinelliae Rhizoma] (Chinese). Xiandai Zhongyao Yanjiu Yu Shijian [Chin Med J Res Prac] 2012;26:79-82
  2. Government of the Hong Kong Special Administrative Region, Chinese Medicine Regulatory Office. [A reference book for Chinese medicines which had been reported as adverse events in Hong Kong] (Chinese). https://www.cmro.gov.hk/html/b5/useful_information/public_health/ publication/AdverseEventsIndex.html, 2013 (last amendment 2020)
  3. Chen L, Zhang HZ and Li GX. [Standardized research on clinical symptoms of ADRs involving the circulatory system] (Chinese). Liaoning Zhong Yiyao Daxue Xuebao [Journal of Liaoning University of TCM] 2015;17:66-69
  4. Yu Y, Huang YM, Wu ZJ, et al. [A study on the changes of calcium oxalate needle crystals in toxic Chinese herbs of the Araceae family before and after processing] (Chinese). Zhong Yao Cai [Journal of Chinese Medicinal Materials] 2014;37:1765-1767
  5. Hu CJ, Nögel R, Hummelsberger J and Engelhardt U. Paozhi: Die Aufbereitung chinesischer Arzneimittel. Berlin: Springer, 2018
  6. Li Y. [Cause analysis of one case of poisoning by prepared Pinelliae Rhizoma] (Chinese). Chuanbei Yixue Yuan Xuebao [Journal of North Sichuan Medical College] 1999;14:76
  7. He TG. [A case of processed Pinelliae Rhizoma poisoning] (Chinese). Zhongguo Xiangcun Yisheng Zazhi [Journal of Chinese Rural Physician] 2008;24:111
  8. Wang XL, Chen X, Ran F, et al. [Successful rescue of a patient with coma due to Qingbanxia poisoning: a case report] (Chinese). Zhongguo Zhong Xiyi Jiehe Jijiu Zazhi [Chin J TCM WM Crit Care] 2014;21:472
  9. Du M. [The application of Fuzi and Banxia] (Chinese). Xiandai Zhong Yiyao [Modern Traditional Chinese Medicine] 2008;28:1-2,16
  10. Tang YR. [One case report of adverse reaction to a formula containing Aconiti Radix, Aconiti kusnezoffii Radix, Fritillariae cirrhosae Bulbus, and Pinelliae Rhizoma] (Chinese). Zhongguo Zhongyi Gu Shan Ke Zazhi [Chinese Journal of Traditional Medical Traumatology & Orthopedics] 1991;7:43-44
  11. Yang YJ. [Analysis of a case of poisoning caused by Aconite combined with Pinelliae Rhizoma] (Chinese). Gansu Zhongyi [Gansu Journal of TCM] 1999;12:12
  12. Guo XJ, Liu AS and Chu TY. [Poisoning by incompatibility of Banxia and Fuzi: report of 2 cases] (Chinese). Shandong Yiyao [Shandong Medical Journal] 2004;44:75
  13. Zhang L, Liu CA, Li WH, et al. [Acute toxicity study on the combination of Aconiti Kusnezoffii Radix with Trichosanthis Fructus, Bletillae Rhizoma and Pinelliae Rhizoma] (Chinese). Shizhen Guoyi Guoyao [Lishizhen Medicine and Materia Medica Research] 2014;25:2616-2618
  14. Zhang ZZ, Liu QW, Zhu HN, et al. [Experimental study on the '18 compatibilities' of Chinese traditional medicine--acute toxicity of Aconitum carmichaeli and Pinellia ternata] (Chinese). Zhongyao Tongbao [Bull Chin Materia Medica] 1983;8:33-34
  15. Liu WL, Song FR, Liu ZQ and Liu SY. [A chemical study on the incompatibility of Radix Aconiti and Pinelliae Tuber] (Chinese). Huaxue Tongbao [Chemistry] 2008;71:435-438
  16. Cao C, Liao WY, Zhang JW, et al. [Adverse reaction analysis of clinical use of Pinellia and Aconitum carmichaeli antagonistic combination based on the literature] (Chinese). Zhongyi Zazhi [J TCM] 2025;66:955-962
  17. Zhao JY. [Summary of adverse reactions of traditional Chinese medicines and its preparations in  the recent 10 years] (Chinese). Yunnan Zhongyi Zazhi [Yunnan Journal of TCM] 1991;12:28-31
  18. Wiebrecht A. Letter to the Editor regarding: Behandlung der (Hyper-)Emesis gravidarum mit Chinesischer Medizin. Chinesische Medizin 2019;34:193-195