When you are in chronic pain, you hope for relief. Acupuncture is a godsend for so many people. Yet most people are unaware that Chinese Herbs can be very helpful in fighting pain too!
If you are in chronic pain, you may think that Acupuncture and other manual therapies are the only way to find relief. But many Acupuncturists also employ Chinese Herbal Medicine to complement the effects of their Acupuncture treatments. While Acupuncture is the primary method of relieving pain in Chinese Medicine, a well crafted formula, customized to the specific needs of each patient, is like a mini Acupuncture treatment in a bottle, which comes in handy for patients who are not able to come in for Acupuncture as frequently as they and their Acupuncturist want.
In this blog, I want to share some info about the premiere Chinese herb for pain. Corydalis (Yan Hu Suo is its Chinese name) is THE most powerful pain fighting herb in the entire Chinese pharmocopeia. In any Chinese Botanical formula for pain, Yan Hu Suo will be the chief herb.
Exciting research is unveiling its power and happy patients are grateful to have a way to increase the time of relief from and maximize the effects of Acupuncture treatments. Below you will find examples of research on Corydalis or Yan Hu Suo, going from lowest to highest quality evidence. Describing evidence as having low or high quality speaks to the ability of a particular study to give us enough information to feel confident in the effectiveness of a treatment before trying something ourselves. As Chinese Medicine and Acupuncture increase in popularity, and more and more money is applied to producing better studies, we are seeing a slow, but steady improvement in the quality of the evidence.
According to the Elotus Clinical Manual of Oriental Medicine, (Chang et al., 2017) “Yan Hu Suo (Rhizoma Corydalis) is one of the strongest and most potent herbs for treatment of pain. It has a strong analgesic effect that is comparable to morphine. In fact, the analgesic effect of Yan Hu Suo (Rhizoma Corydalis) is so strong and reliable that it has been used with satisfactory anesthetic effect in 98 out of 105 patients (93.4%) who underwent surgery” (p. 606). This statement is based on information from a 1973 Chinese Medicine textbook, Hebei New Medicine and Herbology. Below are results of studies listed in databases like PubMed, from basic science research and clinical trials in more recent times.
PubMed: Wang et al. (2016) conducted basic research (using mice) into the anti-nociceptive properties of a Corydalis (Yan Hu Suo) extract, and found that the extract “effectively attenuates acute, inflammatory and neuropathic pain, without causing tolerance” (Abstract).
PubMed: Hu et al. (1994), conducting basic research (using mice), determined that Corydalis (Yan Hu Suo) enhances the analgesic function of concurrent administration of electro-acupuncture.
Proquest: Tong et al. (2015) conducted a Case Series study (uncontrolled longitudinal study) of 132 patients with chronic tension-type headache. Pain levels were assessed at baseline, and 4, 8, and 12 weeks after baseline. Each patient was orally administered a Chinese formula decoction that included Corydalis (Yan Hu Suo), for 10 days. Mean headache scores were significantly (P <.05) lower, by 25 to 40 %, at twelve weeks follow up. In addition, the number of days of headache fell by a significant (P<.05) level, 6.8 to 9.5 days from baseline to each point of follow up. Duration of headache was also significantly (P<.05) lower from 4 to 8 weeks of follow up. Finally, at 4 weeks of follow up, days with medication was lower than at baseline. By week 12 follow up, days with medication had fallen by 56.6% from baseline.
PubMed: Zuo et al. (2015) conducted a controlled clinical study of 79 out and inpatient Chinese patients with knee osteoarthritis, selected from a hospital, to compare the analgesic effects of a Corydalis (Yan Hu Suo) compound with the medication, Diclofenac (used as a control). After 12 weeks of treatment, the total efficacy rates based on patients/physicians’ evaluation for experimental and control groups were without significant difference between the 2 randomized groups. There were significant improvements among both groups in the main efficacy indexes (pain on walking 20 m) and minor indexes (tenderness on palpation, Western Ontario and McMaster Universities OA index (WOMAC) and Short-Form Health Survey (SF-36), without significant differences in efficacy between them. The number of adverse events was significantly (P <.05) greater in the control (Diclofenac) group, at about 47%, which was almost twice that of the treatment (Corydalis compound) group. Researchers determined that the botanical compound was “as efficient as diclofenac…but more tolerable, with a good application prospect” (Abstract).
Proquest: Jin et al. (2017) conducted a controlled clinical study of 234 patients suffering from a mild, but recurring aphthous ulcer. They used a stratified random grouping method to place 177 of these patients into a treatment group (an anti-inflammatory oral liquid with Corydalis as one of its main components), and the rest into a placebo group. Both groups received Vitamin B2. The treatment group had superior clinical outcomes (P<.05) to the control group in terms of days required for ulcer healing and pain abatement. The researchers concluded that “Pudilan anti-inflammatory oral liquid is safe and effective in treating minor RAU and can be used as a first-line treatment” (p. 6)
Proquest: Lee et al., (2015) conducted a systematic review and meta-analysis of Traditional Herbal Medicine treatments for cancer pain, most of which contain Corydalis, and concluded that “results of these studies suggest that THM combined with conventional therapy is efficacious as an adjunctive therapy for patients with cancer pain. However, more research, including well-designed, rigorous, and larger clinical trials, are necessary to address these issues” (Abstract, p. 265).
Conclusion: While there is much data yet to be collected to establish the true effectiveness of an herb like Corydalis for a variety of pain conditions, the data that is present can be evaluated based on the hierarchy of evidence, and integrated with other factors such as clinical expertise, and patient experiences and preferences. If you are in chronic pain, consider starting a course of Acupuncture. After two weeks of care, you and your Acupuncturist/Herbalist can decide together if a customized formula with Corydalis (Yan Hu Suo) is a good addition to your treatment plan.
Chang, J., Chen, J., Huang, L., McNease, C., Ni, M. Tan, R.T., Benschoten, M.V., Wang, C. (2017). Elotus Clinical Manual of Oriental Medicine. City of Industry, CA: Lotus Institute of Integrative Medicine
Hu, J., Xie, J., Hu, J., Zhang, Y., Wang, J., Chen, R. (1994). [Effect of some drugs on electroacupuncture analgesia and cytosolic free Ca2+ concentration of mice brain]. Zhen Ci Yan Jiu. 19(1):55-8. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/?term=Effect+of+some+drugs+on+%09electroacu puncture+analgesia+and+cytosolic+free+Ca2%2B+concentration+of+mice+brain
Jin, Y., Lin, X., Song, L., Liu, M., Zhang, Y. (2017). The Effect of Pudilan Anti-Inflammatory Oral Liquid on the Treatment of Mild Recurrent Aphthous Ulcers. Evidence – Based Complementary and Alternative Medicine. 2017 (2017): 1-6. Retrieved from https://doi.org/10.1155/2017/6250892
Lee, J., Lee, W.B., Kim, W., Min, B., Lee, H.S. (2015). Traditional herbal medicine for cancer pain: A systematic review and meta-analysis. Complementary Therapies in Medicine. 23(2): 265- 274. Retrieved from https://search-proquest- com.pacificcollege.idm.oclc.org/docview/1669616359/fulltextPDF/1B5B22D238FD4F88 PQ/1?accountid=142078
Tong, Y, Yu, L., Sun, Y. (2015) Chinese Herbal Therapy for Chronic Tension-Type Headache. Evidence-Based Complementary and Alternative Medicine. 2015: 1-4. Retrieved from http://dx.doi.org/10.1155/2015/208492
Wang, L., Zhang, Y., Wang, Z., Gong, N., Kweon, T.D., Vo, B., Wang, C., Zhang, X., Chung, J.Y., Alachkar, A., Liang, X., Luo, D.Z., Civelli, O. (2016). The Antinociceptive Properties of the Corydalis yanhusuo Extract. PLoS One. 11(9): e0162875. doi: 10.1371/journal.pone.0162875
Zuo, C., Yin, G., Cen, X.M., Xie, Q.B. (2015). Controlled clinical study on compound Decumbent Corydalis Rhizome and diclofenac in treatment of knee osteoarthritis. Zhongguo Zhong Yao Za Zhi. 40(1):149-53. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/?term=Controlled+clinical+study+on+compound +Decumbent+Corydalis+Rhizome+and+diclofenac+in+treatment+of+knee+osteoarthritis