Benefits
Urinary symptom scores in men with moderate symptoms
In 80 Korean men aged 40 to 75 with moderate urinary symptoms, 600 mg a day of a self-heal spike extract for 12 weeks lowered the symptom score and its quality-of-life item more than placebo. Urine flow, PSA and hormone levels did not differ. It is one trial, co-authored by staff of the extract maker, and its abstract and tables report different numbers.
Thyroid markers when added to standard drug care
In Chinese hospital trials of people with a diagnosed overactive thyroid, autoimmune thyroiditis or thyroid nodules, adding a self-heal oral preparation to standard drugs was linked to larger shifts in thyroid hormone levels and gland size than the drugs alone. Reviews rated the trials low or very low quality. This is research on medical care, not a use for healthy people.
Estrogen-related activity in cell and mouse studies
In lab work, a self-heal extract blunted estrogen-driven growth of human uterine-lining cells, apparently through the aryl hydrocarbon receptor rather than by blocking estrogen directly. Mice given self-heal tea in their drinking water grew fewer and smaller estrogen-fed tissue implants. These are cell and animal findings only; no human study has measured this.
Blood glucose response in mouse studies
In mice with chemically induced diabetes, a self-heal spike extract lowered blood glucose, strengthened the effect of injected insulin and added to the effect of the drug glibenclamide, without raising insulin release. These are animal findings only; no trial has measured blood sugar in people taking self-heal.
Mechanism of action
Rosmarinic acid and triterpenes are the main measured compounds
Reviews list triterpenoids, flavonoids, phenylpropanoids, organic acids and polysaccharides in the spike, and HPLC of a commercial oral solution found caffeic and rosmarinic acids as its main components. In a gut-lining cell model, rosmarinic acid from a self-heal extract crossed poorly, while ursolic acid, tested from a sage extract, crossed more readily.
Aryl hydrocarbon receptor signaling and estrogen crosstalk
In human uterine-lining cells, self-heal extract switched on aryl hydrocarbon receptor target genes (CYP1A1, CYP1B1), and blocking that receptor stopped this gene response. The extract did not appear to block estrogen signaling directly. Cell and mouse work only.
Inflammatory signaling in immune cells
A purified triterpenoid fraction of the spike reduced nitric oxide, IL-6, IL-1β and TNF-α output from stimulated mouse macrophages and pointed to the NF-κB/TLR/TNF-α pathway. This is a concentrated fraction tested in cells and mice, not the whole herb in people.
Androgen and cell-growth effects in rats
In rats given testosterone to enlarge the prostate, oral self-heal extract lowered prostate weight, DHT and testosterone and reduced markers of cell growth. The study was co-authored by staff of the company that made the extract later tested in men. Animal findings only.
Clinical trials
Randomized, double-blind, placebo-controlled trial of a self-heal spike ethanol extract (HFN2-007), 600 mg/day for 12 weeks, at the Catholic University of Korea. Two co-authors list affiliations with Huons Foodience, which manufactured the extract, and one of them did the formal analysis, yet the paper declares no conflicts of interest; funding came from a Korean government startup program. (Kim et al. 2026, World J Mens Health)
80 men aged 40 to 75 (the methods section says 40 to 80) with moderate lower urinary tract symptoms (IPSS 8 to 19, PSA under 4.0 ng/mL); 75 completed (39 extract, 36 placebo).
The abstract reports a larger drop in total IPSS with the extract than placebo (-5.2 vs -2.8 points; p = 0.014), while the full-text table reports -6.85 vs -1.46 (p < 0.0001); both favor the extract. Quality of life also improved more (abstract p = 0.044; table p < 0.0001). Peak urine flow, residual volume, PSA, testosterone, DHT and erectile scores did not differ. The abstract reports no difference in prostate volume, but the paper says prostate volume was not measured by transrectal ultrasound. No adverse events in the extract group.
PROSPERO-registered systematic review and meta-analysis of randomized trials from eight Chinese and English databases comparing self-heal preparations plus antithyroid drugs with the drugs alone. (Wei et al. 2025, Front Pharmacol)
17 trials with 1,366 patients with an overactive thyroid.
Adding self-heal was linked to larger falls in free T3, free T4 and TSH receptor antibodies, a larger rise in TSH and smaller thyroid lobe measurements than drugs alone, with no difference in relapse rates. The authors rated the strength of evidence low and asked for higher-quality trials.
Meta-analysis of randomized trials from eight databases up to April 2021, comparing self-heal preparations plus levothyroxine or thyroid tablets with the tablets alone. (Han et al. 2021, Medicine (Baltimore))
13 trials with 1,468 patients with thyroid nodules.
The pooled response rate was higher with self-heal plus levothyroxine (risk ratio 1.22, 95% CI 1.11 to 1.33), and nodule diameter fell more (mean difference -0.43). Adverse reactions did not differ significantly (risk ratio 0.67, 95% CI 0.36 to 1.22). The authors called the quality of the trials uncertain.
Randomized trial (Chinese-language, English abstract) of a self-heal oral liquid added to standard treatment versus standard treatment alone, with thyroid size measured by color Doppler ultrasound. (Yang et al. 2007, Zhongguo Zhong Xi Yi Jie He Za Zhi)
98 patients with goiter at a hospital in Hubei, China (56 with an overactive thyroid, 24 with an underactive thyroid and 18 with simple goiter), plus 20 healthy people as an ultrasound reference.
Thyroid size shrank in both groups; after treatment only the self-heal group no longer differed from the healthy reference group. The abstract gives no direct statistical comparison between the two treatment groups, so it does not show a between-group effect.
NIH-supported cell-culture and mouse xenograft study that screened herbs for anti-estrogen activity. (Collins et al. 2009, Biol Reprod)
Human uterine-lining (ECC-1) cells, and immunodeficient mice implanted with human uterine-lining tissue and given estrogen, with or without self-heal tea in their drinking water. No human participants.
The extract cut estrogen-driven alkaline phosphatase activity and cell growth, probably by acting through the aryl hydrocarbon receptor. Mice drinking self-heal tea had fewer and smaller implants (P < 0.05), with no change in uterine weight or in the fertility cycles of normal female mice. Animal and cell findings only.
Animal study of an aqueous-ethanol self-heal spike extract at four doses in mice with diabetes induced by streptozotocin. (Zheng et al. 2007, Asia Pac J Clin Nutr)
ICR mice with streptozotocin-induced diabetes. No human participants.
At 100 mg/kg, the extract blunted the blood glucose rise in a glucose tolerance test and lowered blood glucose over the treatment period. It added to the effect of glibenclamide and prolonged the effect of injected insulin, without raising plasma insulin. Animal findings only.