Written by Jianping Liu, Xun Li and the CAM-Cancer Consortium.
Updated March 9, 2017

Black cohosh (Actaea racemosa)

Is it safe?

Adverse events

The minor adverse effects observed in clinical studies include nausea, vomiting, headaches, dizziness, mastalgia, and weight gain 18-20.

The above mentioned systematic review by Walji et al. of black cohosh in cancer patients concluded that black cohosh seems to have a relatively good safety profile 14. Another systematic review of black cohosh’s safety in general (not only cancer patients) retrieved 13 clinical trials involving more than 2,800 patients 21. All trials indicate relative safety: 97% of all the reported adverse effects were minor, and the only severe ones were not deemed to be related causally to black cohosh. This is in line with the findings of an earlier review 22. Recent clinical trials in general populations confirm these findings 23-26.

In response of the "potential association" between black cohosh and hepatotoxicity, a systematic review published in 2008 by the Dietary Supplement Information Expert Committee of the US Pharmacopeia's Council of Experts on the hepatotoxicity found all the reports of liver damage were assigned possible causality, and none were of probable or certain causality 27. The clinical pharmacokinetic and animal toxicological information did not reveal unfavourable information about black cohosh.

Fritz et al did not systematically assess the impact of black cohosh on liver function but reported no impact on liver function or symptoms suggestive of impaired liver function among the studies the included in their review 13.

A systematic review published in 2011 including five randomized double-blind clinical trials involving 1,117 women who were treated daily with black cohosh extract for 3 to 6 months also found no evidence that it had any adverse effect on liver function 28. These confirms the findings of the 2007 systematic review by Walji including five RCTs and 21 pre-clinical studies of cancer patients 13.

The eight most recent papers reviewing published and spontaneous case reports (numbers ranging from 22 to 75) of initially alleged black cohosh hepatotoxicity were identified. All surveys found a lack of causality for the herbal medicine in all cases 29-36


Pre-existing liver damage is a contraindication.


Black cohosh was found to alter the response to the agents commonly used to treat breast cancer in an experiment report using mouse breast cancer line 37. In this experiment, the black cohosh extracts increased the cytotoxicity of doxorubicin and docetaxel and decreased the cytotoxicity of cisplatin.


Based on the safety review by the Dietary Supplement Information Expert Committee 27, it was determined that black cohosh products should be labelled to include a cautionary statement. This is a change from the Expert Committee's decision of 2002, which required no such statement

Citation Jianping Liu, Xun Li, CAM-Cancer Consortium. Black cohosh (Actaea racemosa) [online document]. http://ws.cam-cancer.org/The-Summaries/Herbal-products/Black-cohosh-Actaea-racemosa. March 9, 2017.


  1. Piersen CE. Phytoestrogens in botanical dietary supplements: implications for cancer. Integr Cancer Ther 2003; 2(2): 120-38.
  2. Popp M, Schenk R, Abel G. Cultivation of Cimicifuga racemosa (L.) nuttal and quality of CR extract BNO 1055. Maturitas 2003; 44 (Suppl 1):S1-7.
  3. Mahady GB, Fabricant D, Chadwick LR, Dietz B. Black cohosh: an alternative therapy for menopause? Nutr Clin Care 2002;5(6):283-9
  4. Anonymous. Cimicifuga racemosa. Monograph. Alternative Medicine Review 2003; 8(2):186-9.
  5. Blumenthal M, ed. Herbal Medicine: Expanded Commission E Monograph. 1st ed. Newton, Mass: Integrative Medicine Communications; 2000.
  6. Rossouw JE, Anderson GL, Prentice RL, LaCroix AZ, Kooperberg C, Stefanick ML, Jackson RD, Beresford SA, Howard BV, Johnson KC, Kotchen JM, Ockene J; Writing Group for the Women's Health Initiative Investigators. Risks and benefits of estrogen plus progestin in healthy postmenopausal women: principal results From the Women's Health Initiative randomized controlled trial. JAMA. 2002;288(3):321-33.
  7. Schairer C, Lubin J, Troisi R, Sturgeon S, Brinton L, Hoover R. Menopausal estrogen and estrogen-progestin replacement therapy and breast cancer risk. JAMA. 2000;283(4):485-91.
  8. Graf MC, Geller PA. Treating hot flushes in breast cancer survivors: a review of alternative treatments to hormone replacement therapy. Clin J Oncol Nurs 2003;7(6):637-40.
  9. Einer-Jensen N, Zhao J, Andersen KP, Kristoffersen K. Cimicifuga and Melbrosia lack oestrogenic effects in mice and rats. Maturitas 1996;25:149-53.
  10. Kruse SO, Lohning A, Pauli GF, Winterhoff H, Nahrstedt A. Fukiic and piscidic acid esters from the rhizome of Cimicifuga racemosa and the in vitro estrogenic activity of fukinolic acid. Planta Med 1999; 65(8):763-4.
  11. De Smet P. Herbal medicine in Europe – relaxing regulatory standards. N Engl J Med 2005;352:1176-8.
  12. Medicines and Healthcare products Regulatory Agency. Guidance: Herbal Medicines Granted a Traditional Herbal Registration (THR), updated 7th March 2017. Available at: https://www.gov.uk/government/publications/herbal-medicines-granted-a-traditional-herbal-registration-thr/herbal-medicines-granted-a-traditional-herbal-registration, accessed 9th March 2017.
  13. Fritz H, Seely D, McGowan J, Skidmore B, Fernandes R, Kennedy DA, Cooley K, Wong R, Sagar S, Balneaves LG, Fergusson D. Black cohosh and breast cancer: a systematic review. Integr Cancer Ther. 2014;13(1):12-29.
  14. Walji R, Boon H, Guns E, Oneschuk D, Younus J. Black cohosh (Cimicifuga racemosa [L.] Nutt.): safety and efficacy for cancer patients. Support Care Cancer. 2007;15(8):913-21.
  15. Tamaki H, Satoh H, Hori S, Ohtani H, Sawada Y. Inhibitory effects of herbal extracts on breast cancer resistance protein (BCRP) and structure-inhibitory potency relationship of isoflavonoids. Drug Metab Pharmacokinet. 2010;25(2):170-9.
  16. Einbond LS, Soffritti M, Esposti DD, Wu HA, Tibaldi E, Lauriola M, He K, Park T, Su T, Huggins L, Wang X, Roller M, Brennan R. Pharmacological mechanisms of black cohosh in Sprague-Dawley rats. Fitoterapia. 2012 Apr;83(3):461-8.
  17. Einbond LS, Soffritti M, Degli Esposti D, Tibaldi E, Lauriola M, Bua L, He K, Genovese G, Su T, Huggins L, Wang X, Roller M, Wu HA. Chemopreventive potential of black cohosh on breast cancer in Sprague-Dawley rats. Anticancer Res. 2012;32(1):21-30.
  18. Zava DT, Dollbaum CM, Blen M. Estrogen and progestin bioactivity of foods, herbs, and spices. Proc Soc Exp Biol Med 1998;217:369-78.
  19. Wu XS. Remifemin improve gynecological malignant tumor postoperative patients of menopause syndrome for the clinical research. Dissertation for Master Degree of Dalian Medical University 2011; 1-20.
  20. Huang XF. The clinical research of Black cohosh extract in breast cancer patients with climacteric complaints. Dissertation for Master Degree of Manjing University of Chinese Medicine 2011;10-21.
  21. Borrelli F. Ernst E. Black cohosh (Cimicifuga racemosa): a systematic review of adverse events. American Journal of Obstetrics & Gynecology 2008;199(5):455-66.
  22. Huntley A. The safety of black cohosh (Actaea racemosa, Cimicifuga racemosa). Expert Opin Drug Saf 2004; 3(6):615-23.
  23. Ross SM. Menopause: a standardized isopropanolic black cohosh extract (remifemin) is found to be safe and effective for menopausal symptoms. Holist Nurs Pract. 2012;26(1):58-61.
  24. Bai WP, Wang SY, Liu JL, Geng L, Hu LN, Zhang ZL, Chen SL, Zheng SR. Efficacy and safety of remifemin compared to tibolone for controlling of perimenopausal symptoms. Chinese Journal of Obstetrics and Gynecology 2009;44(8): 597-600.
  25. Li YL, Cui MH, Gao S. Efficacy of remifemin for control of climacteric symptoms. Progress in Obstetrics and Gynecology 2011;20(6): 462-65.
  26. Sun NX, Jin ZJ, Jia XF, Li W. Black cohosh improves vaginal atrophy in postmenopausal women. Academic Journal of Second Military Medical University 2012;33(3): 339-42.
  27. Mahady GB. Low Dog T. Barrett ML. Chavez ML. Gardiner P. Ko R. Marles RJ. Pellicore LS. Giancaspro GI. Sarma DN. United States Pharmacopeia review of the black cohosh case reports of hepatotoxicity. Menopause 2008;15(4 Pt 1):628-38.
  28. Naser B, Schnitker J, Minkin MJ, de Arriba SG, Nolte KU, Osmers R. Schaper & Brümmer GmbH & Co. KG, Salzgitter, Germany. Suspected black cohosh hepatotoxicity: no evidence by meta-analysis of randomized controlled clinical trials for isopropanolic black cohosh extract. Menopause. 2011;18(4):366-75.
  29. Teschke R, Schwarzenboeck A, Schmidt-Taenzer W, Wolff A, Hennermann KH. Herb induced liver injury presumably caused by black cohosh: a survey of initially purported cases and herbal quality specifications. Ann Hepatol. 2011;10(3):249-59.
  30. Teschke R, Schmidt-Taenzer W, Wolff A. Spontaneous reports of assumed herbal hepatotoxicity by black cohosh: is the liver-unspecific Naranjo scale precise enough to ascertain causality? Pharmacoepidemiol Drug Saf. 2011;20(6):567-82.
  31. Firenzuoli F, Gori L, Roberti di Sarsina P. Black cohosh Hepatic Safety: Follow-Up of 107 Patients Consuming a Special Cimicifuga racemosa rhizome Herbal Extract and Review of Literature. Evid Based Complement Alternat Med. 2011;2011:821392.
  32. Huang Y, Jiang B, Nuntanakorn P, Kennelly EJ, Shord S, Lawal TO, Mahady GB. Fukinolic acid derivatives and triterpene glycosides from black cohosh inhibit CYP isozymes, but are not cytotoxic to Hep-G2 cells in vitro. Curr Drug Saf. 2010;5(2):118-24.
  33. Teschke R. Black cohosh and suspected hepatotoxicity: inconsistencies, confounding variables, and prospective use of a diagnostic causality algorithm. A critical review. Menopause. 2010;17(2):426-40.
  34. Teschke R, Bahre R, Fuchs J, Wolff A. Black cohosh hepatotoxicity: quantitative causality evaluation in nine suspected cases. Menopause. 2009;16(5):956-65.
  35. Teschke R, Bahre R, Genthner A, Fuchs J, Schmidt-Taenzer W, Wolff A. Suspected black cohosh hepatotoxicity--challenges and pitfalls of causality assessment. Maturitas. 2009;63(4):302-14.
  36. Teschke R, Schwarzenboeck A. Suspected hepatotoxicity by Cimicifugae racemosae rhizoma (black cohosh, root): critical analysis and structured causality assessment. Phytomedicine. 2009;16(1):72-84.
  37. Rockwell S, Liu Y, Higgins SA. Alteration of the effects of cancer therapy agents on breast cancer cells by the herbal medicine black cohosh. Breast Cancer Res Treat. 2005;90(3):233-9.