Primary Dysmenorrhea

Bowen Xu et al. (2026) · Frontiers in endocrinology

This open-label randomized trial at Shanghai East Hospital compared two approaches to primary dysmenorrhea (menstrual cramping without an underlying pelvic disease) in 80 women aged 15 to 46: a Traditional Chinese Medicine protocol called Cai's Gynecology Cyclical Therapy, paired with a specific formula called the Stasis-Clearing and Meridian-Warming Method, versus standard ibuprofen. The TCM approach is built on a century-old idea from a Shanghai medical lineage: that treatment should change across the four phases of the menstrual cycle rather than staying the same throughout. Forty women received ibuprofen (a common anti-inflammatory pain reliever) for two days during each period, while the other forty received herbal decoctions -- different formulas depending on the cycle phase -- for three full menstrual cycles. Researchers tracked pain on a 0-to-10 visual pain scale and a symptom-severity score, and checked whether pain returned in the month after treatment ended. People collecting the follow-up data did not know which treatment each woman had received. Both treatments worked well overall (97.5% of women improved in each group), but the pattern of improvement differed. Ibuprofen relieved pain faster in the first month, as expected for a direct pain reliever. The herbal treatment started more slowly but kept improving month after month, and by the third month the two treatments were statistically equivalent on both pain and symptom scores. The most striking difference came after treatment stopped: only about 13% of the herbal-treatment group had their pain return the following month, compared to about 90% of the ibuprofen group. No side effects were reported in either group throughout the study. The researchers suggest this gap in relapse rates may reflect a real difference in how the two approaches work -- ibuprofen blocks pain-causing chemicals only while it is being taken, whereas the herbal protocol may produce a more lasting change. However, because patients and treating doctors could not be kept unaware of which treatment they were giving or receiving (an inherent challenge when comparing herbal decoctions to a standard pill), and because the study involved one hospital and a single follow-up cycle, the authors call for larger, multi-site studies with longer follow-up to confirm these findings.

Jihye Seo et al. (2020) · Medicine

This systematic review and meta-analysis pooled 14 randomized controlled trials (1,215 women, mostly from China with one from Japan) exploring whether Dangguijagyag-san (DJS) - a traditional East Asian herbal formula also called Danggui Shaoyao San - helps primary dysmenorrhea (PD), the cramping menstrual pain that occurs without an underlying pelvic disease. PD is common, estimated to affect 16-91% of women of reproductive age, and is driven by elevated uterine prostaglandins causing muscle spasm; standard NSAID and hormonal treatments carry gastrointestinal and other side-effect risks, which is part of why researchers keep examining herbal alternatives. The review followed a pre-registered protocol and searched eight medical databases through April 2019. The included trials compared DJS - most often prepared as a decoction (a boiled herbal liquid), given over roughly three menstrual cycles - against NSAIDs (5 trials), a placebo (1 trial), other herbal formulas (6 trials), or NSAIDs with moxibustion added to DJS (2 trials). The main outcome tracked was the total effective rate, a practitioner-judged measure of symptom improvement, alongside pain scores on a visual analogue scale in some trials. Pooled results favored DJS across every comparison. Against NSAIDs, DJS produced a higher effective rate (relative risk 1.16, meaning about 16% more improvement events, 95% confidence interval 1.08-1.24, with no meaningful variation between trials). Against placebo, DJS reduced pain scores and cut how often women needed rescue pain medication during their period. Against other herbal formulas, DJS again showed a higher effective rate (RR 1.24), an advantage that held up most consistently when DJS was prepared as a decoction rather than a granule or capsule. Adding moxibustion (heated-herb therapy at acupuncture points) to DJS outperformed NSAIDs alone (RR 1.47). Side effects were reported in only a handful of trials and were mostly mild digestive complaints, less frequent in the DJS groups than the NSAID groups. The review's authors rated the overall certainty of this evidence as moderate to low: most trials did not clearly describe how they randomized or concealed group assignment, could not blind participants to which herbal or drug treatment they were taking, and were often small (many under 100 participants), all conducted in East Asia. The findings do not establish how DJS performs in other populations or over longer treatment periods, and the authors call for larger, more rigorously designed trials to confirm the effect.

Ziqing Soh et al. (2025) · Journal of food and drug analysis

This double-blind, randomized, placebo-controlled trial with 30 young Malaysian women explored whether a beverage combining chamomile and l-theanine could ease primary dysmenorrhea - menstrual cramping that occurs without any underlying pelvic disease. Chamomile (Matricaria recutita) is a flowering herb long used as a calming remedy; the study intervention used a standardized flower extract of it. L-theanine is a non-protein amino acid concentrated in tea leaves (Camellia sinensis), used in supplements to support relaxation. The trial paired both in a functional beverage (CTT) and tested it against a chamomile-flavored placebo (non-CTT) to see whether the combination eased pain, mood, and sleep during menstruation. Thirty women aged 18-30 with primary dysmenorrhea (pain rated at least 4 of 10 on a visual scale across three cycles) were randomly split into a CTT group (480 mg chamomile extract plus 200 mg l-theanine daily) or a non-CTT control group, drinking two 240 mL packs daily - one on waking, one before bed - for five days spanning two days before their period through its third day. Pain was tracked with two 0-10 scales, symptoms with the 18-item Cox Menstrual Symptom Scale, sleep with the Pittsburgh Sleep Quality Index, and mood with the Profile of Mood States. Compared to their own baseline, women drinking CTT saw pain scores drop by roughly 57% on both pain scales (p<0.001), a large reduction over five days. Eight menstrual symptoms also eased significantly, including lower abdominal pain (down 53%), back pain (down 56%), and irritability (down 45%, all p<0.05). Mood shifted too: depression scores fell 12% and vigor (energy and alertness) rose 62% (p<0.05). On sleep, only "daytime dysfunction" - grogginess, poor concentration, and low energy during the day - improved (down 32%, p<0.05); overall sleep quality, how long it took to fall asleep, and total sleep time did not change significantly. Hemoglobin levels, checked with a finger-prick test, were unaffected in either group, likely because red blood cells take weeks to months to regenerate, too slow to show up in five days. Interestingly, the placebo group also felt calmer on a few measures, which the researchers link to the shared chamomile scent and flavor rather than to any active ingredient. For young women managing primary dysmenorrhea without relying on NSAIDs, a short course of this chamomile-l-theanine beverage appears to meaningfully ease pain and several physical and emotional symptoms, with no reported side effects. Because chamomile and l-theanine were only tested together, it is not yet clear how much each contributes individually, and the tiny sample (15 per group) and single five-day cycle mean the results are preliminary. Longer trials spanning multiple cycles, larger and more diverse groups, and a scent-neutral placebo are needed before firmer conclusions can be drawn.