Help Fund Clinical Trial on Primary Dysmenorrhea

By Ryan Bradley, ND, MPH, and Christine McClure

Do you have patients that experience Primary Dysmenorrhea (PDM)? Up to 90% of menstruating women in the United States experience PDM1 which is defined as pelvic pain directly before or during menstruation in the absence of a known pathology.1

Conventional treatment options for PDM include nonsteroidal anti-inflammatory drugs (NSAIDs) and oral contraceptives (OCs).1

NSAIDs are generally safe when used in low doses for short time periods, but toxicity increases with increased dose and duration of the drug.2 In just a few days of use, gastrointestinal bleeding is observed in 41% of NSAID users3 and a number of adverse events have been shown to occur in clinical trials.3 Chronic use of NSAIDs results in: dyspepsia interfering with quality of life in 30% of users, gastrointestinal lesions in 35-60% of users, and gastric ulcerations in up to 25% of users.3 For PDM, NSAIDs are regularly prescribed to patients in dosages of 400 to 600 mg every four to six hours, or 800 mg every eight hours, beginning a few days before initiation of menses and continuing medication until the second or third day of menses.4

Oral contraceptive use is also associated with long-term risk. Long-term adverse events include an increased risk of cardiovascular disease, hypertension, stroke, venous thromboembolism, cervical cancer, and mild insulin resistance.5 Additionally, there is a lack of high-quality evidence to support the effectiveness of OCs for PDM.5

Pau d’ Arco (Tabebuia avellanedae) is a native Bignoniaceae tree located in Central and South America, the inner bark of which has been used medicinally for over 1,000 years.6 Tabebuia avellanedae has been shown to inhibit the expression of prostaglandin E2 and cyclooxygenase-27 in laboratory studies and has also been shown to be anti-inflammatory and to decrease pain responses in animal studies.6 Additionally, Tabebuia avellanedae has been shown to have antiulcerogenic properties, and to possibly be gastroprotective.8 Tabebuia avellanedae has not been associated with major adverse effects in human clinical trials.9

Ryan Bradley, ND, MPH and student Christine McClure are conducting a single arm, open label trial evaluating safety and tolerability of Pau d’ Arco as a natural alternative for PDM. This trial is Christine’s thesis as she completes her Naturopathic Doctor degree and Master of Science in Integrative Medicine Research degree at the National University of Natural Medicine.

Unfortunately, this trial will not exist without funding. A new method of raising research funding is being tried with an Indiegogo campaign, to raise the money needed to complete the trial above. This campaign is a student research project based on the social good of deceasing women’s pain. Additionally, this helps naturopathic medicine by increasing positive visibility of our profession and adding to our evidence base.

So please donate and share this campaign!

About the Authors

Ryan Bradley, ND, MPH received his Doctor of Naturopathy from Bastyr University in 2003 and his Master of Public Health in Epidemiology from the University of Washington in 2009. His primary academic appointment is as the Director of Research and Associate Professor at the National University of Natural Medicine in Portland, OR. He is also faculty in the Division of Preventive Medicine at the University of California, San Diego, an Affiliate Associate Professor in the School of Pharmacy at the University of Washington in Seattle, and a Visiting Professor at the University of Technology, Sydney in Sydney, Australia. He is licensed in WA, OR and CA and maintains a private practice in addition to his research and teaching in academia. Bradley has conducted a wide-variety of epidemiologic, translational and practice-based research focused on complementary and integrative medicine, and he has been published in leading peer-reviewed medical journals. He is a highly-rated international speaker on naturopathic medicine, integrative medicine research, and clinical cardio-renal-metabolic disorders. When not working, Ryan enjoys playing in nature.

Christine McClure is a fourth year student at the National University of Natural Medicine, obtaining a Doctorate in Naturopathic Medicine and a Master of Science in Integrative Medicine Research. Her thesis for her master’s degree is a clinical trial titled, “The effects of Pau d’ Arco on primary dysmenorrhea.” Before transitioning to NUNM, she obtained a bachelor’s degree in psychology and a bachelor’s degree in women’s studies from Kansas State University. Her primary focus in medicine and research is women’s health. Combining clinical experience and a focus in research, Christine plans to pursue a residency and postdoctoral fellowship after graduation.


  1. Coco AS. Primary dysmenorrhea. American Family Physician. 1999; 60(2): 489-496.
  2. Solomon DH. NSAIDs: Therapeutic use and variability of response in adults. In: UpToDate, Post TW (Ed), UpToDate, Waltham, MA. Updated August 23, 2017. Accessed January 4, 2018.
  3. Halter F, Tarnawski AS, Schmassmann A, Peskar BM. Cyclooxygenase 2-implications on maintenance of gastric mucosal integrity and ulcer healing: controversial issues and perspectives. Gut. 2001; 49(3): 443. 
  4. Smith RP, Kaunitz AM. Treatment of primary dysmenorrhea in adult women. In: UpToDate, Post TW (Ed), UpToDate, Waltham, MA. (Accessed May 11, 2017).
  5. Proctor M, Farquhar C. Diagnosis and management of dysmenorrhea. British Medical Journal. 2006; 332: 1134. 
  6. Lee MH, Choi HM, Hahm D-H, et al. Analgesic and anti-inflammatory effects in animal models of an ethanolic extract of Taheebo, the inner bark of Tabebuia avellanedae. Molecular Medicine Reports. 2012; 6(4): 791-796.
  7. Byeon SE, Chung JY, Lee YG, Kim BH, Kim KH, Cho JY. In vitro and in vivo anti-inflammatory effects of taheebo, a water extract from the inner bark of Tabebuia avellanedae. Journal of Ethnopharmacology. 2008; 119(1); 145-152. 
  8. Twardowschy A, Freitas CS, Baggio CH, et al. Antiulcerogenic activity of bark extract of Tabebuia avellanedae, Lorentz ex Griseb. Journal of Ethnopharmacology. 2008; 118(3): 455-459.
  9. Suzuki N, Arai T, Uebaba K, Nakai M, Suzuki R, Takimoto Y. Clinical safety test of the long-term intake of Tabebuia avellanedae (Taheebo) in cancer patients. Japanese Journal of Complementary and Alternative Medicine. 2011; 8(2); 174-193.