Promensil, does it work for hot flashes?
July 1 2017 by
Ray Sahelian, M.D.

Promensil is a dietary supplement that contains red clover. A search in 2014 yielded only three studies with Promensil in the medical literature, and none in recent years. One out of three studies showed it to be effective for hot flashes. Promensil was launched in Australia in 1997 and is distributed by Novogen, a company involved in isoflavone production. Each tablet of Promensil is standardized to contain a total of 40 mg of four standardized isoflavones, genistein, daidzein, formononetin and biochanin sourced from red clover (Trifolium pratense).

No conclusive evidence shows that phytoestrogen supplements effectively reduce the frequency or severity of hot flushes and night sweats in perimenopausal or postmenopausal women, although benefits derived from concentrates of genistein should be further investigated.

Promensil Research
Effect of isoflavones on lipids and bone turnover markers in menopausal women.
Maturitas. 2004. Schult TM. Center for Chronic Disease Outcomes Research, Minneapolis VA Medical Center, MN, USA
The purpose of this analysis was to compare the effects of two dietary supplements derived from red clover to placebo on lipids and bone turnover markers in symptomatic menopausal women. The study was a 12-week randomized, double-blind, placebo-controlled trial. Two hundred and fifty-two menopausal women ages 45-60 years experiencing greater or =35 hot flashes per week were randomly assigned to Promensil (82 mg total isoflavones), Rimostil (57 mg total isoflavones), or placebo. Primary outcome measures were mean absolute changes for HDL-cholesterol, serum osteocalcin, and urinary N-telopeptide. Secondary outcome measures were mean changes of total cholesterol, LDL-cholesterol, the ratio of HDL- to LDL-cholesterol, and triglycerides. Women taking Rimostil or Promensil compared to those taking placebo had greater mean increases in HDL-cholesterol; however, this change was small in magnitude (<2 mg/dl) and did not reach significance. There was a significant decrease in triglyceride levels among women taking Rimostil (14 mg/dl) or Promensil (10.9 mg/dl) compared to those taking placebo. The decrease was primarily among women with elevated baseline triglyceride levels. There were no differences in mean changes of total cholesterol, LDL-cholesterol, or the ratio of HDL- to LDL-cholesterol among treatment groups. There were no statistically significant differences among treatment groups for bone turnover markers. Compared with placebo, both of the supplements containing isoflavones decrease levels of triglycerides in symptomatic menopausal women; however, this effect is small in magnitude.

Isoflavones from red clover Promensil significantly reduce menopausal hot flush symptoms compared with placebo.
Maturitas. 2002. Department of Obstetrics and Gynecology, Vrije Universiteit Medical Centre, Amsterdam, The Netherlands.
To investigate the effectiveness and safety of a red clover isoflavone dietary supplement (Promensil, Novogen Ltd., Australia) versus placebo on the change in hot flush frequency in postmenopausal women. In this randomized, double blind, placebo-controlled trial 30 women with more than 12 months amenorrhoea and experiencing more than five flushes per day were enrolled. All received single blind placebo tablets for 4 weeks and were subsequently randomized to either placebo or 80 mg isoflavones for a further 12 weeks. Efficacy was measured by the decrease in number of hot flushes per day and changes in Greene Climacteric Scale Score. During the first 4 weeks of placebo the frequency of hot flushes decreased by 16%. During the subsequent double blind phase, a further, statistically significant decrease of 44% was seen in isoflavones group, whereas no further reduction occurred within the placebo group. The Greene score decreased in the active group by 13% and remained unchanged in the placebo group. Treatment with 80 mg isoflavones (Promensil) per day resulted in a significant reduction in hot flushes from baseline. At the end of the study there was a significant decrease in hot flushes of 44% between the active and placebo group, demonstrating the effectiveness of Promensil in the management of hot flushes.

The effect of Promensil, an isoflavone extract, on menopausal symptoms.
Climacteric. 1999. Caroline Chisholm Centre for Women and Children, Liverpool Hospital, Liverpool.
The primary aim was to assess whether the use of an isoflavone extract containing 40 mg or 160 mg of total isoflavones affects the frequency of menopausal flushes and other symptoms. The secondary aims were assessments of possible effects on menopause symptom scores and biological measures of estrogen activity. A randomized, double-blind, placebo-controlled prospective trial of 37 postmenopausal women with symptoms of estrogen deficiency was performed over a 12-week period. The women were randomized to three treatment groups: placebo, 40 mg or 160 mg, delivered in tablet form. There was no significant difference in the incidence of flushes between the three groups at trial conclusion. There was no difference between the groups in Greene Menopause Symptom Scores, vaginal pH, levels of follicle stimulating hormone (FSH), sex hormone binding globulin (SHBG) or total cholesterol, liver function or blood parameters. A statistically significant increase in high-density lipoprotein (HDL) cholesterol of 18% occurred in the 40-mg group. A large placebo response and inadvertent use of dietary isoflavones in the placebo group may have obscured a significant change in flushing frequency. Previous uncontrolled studies claiming a beneficial effect of foods with a high isoflavone content on menopausal symptoms may have been confounded by a large placebo response.

April 2008 Promensil study - press release
Natrol, Inc., the exclusive U.S. licensee for Promensil, announces the results of a large, three-year study -- published last month in the journal Menopause International ( -- reinforcing the safety of this red clover isoflavone supplement for managing hot flashes and other menopausal symptoms. This new study shows that Promensil, containing a standardized supplement of red clover isoflavones, has a neutral effect on breast density in women with a family history of breast cancer. This is in contrast to studies showing that some conventional hormone replacement therapies (HRT) increase mammographic breast density. Professor Trevor Powles, consultant oncologist and the study's lead investigator, said, "Reassuringly for women, this study shows that these phytoestrogens don't cause any estrogenic increase in breast density in women with a family history of breast cancer. This indicates that they are unlikely to cause an increased risk of breast cancer. This three-year study confirms similar findings from previous, shorter-term studies." Tens of thousands of women around the world use Promensil daily. It has been recommended by menopause experts as a natural alternative to help control hot flashes and other symptoms associated with menopause, used alongside lifestyle changes.
   This red clover isoflavone breast cancer safety study took place in the UK, and has implications for women worldwide. Over 400 healthy women with at least one first-degree relative with breast cancer were studied. The women received a standardized supplement of 40mg red clover isoflavones ( Promensil ) or placebo for three years in a randomized, double-blind, placebo-controlled trial. Results showed that Promensil did not adversely affect breast density, skeletal strength, or cardiovascular status. In post-menopausal women, endometrial status was not adversely affected. The adverse event profile was similar between Promensil and placebo groups.

In 2006, Natrol acquired the licensing rights to market Promensil in the U.S. Promensil was developed by Novogen Limited, which launched the product in Australia in 1997. Today, Promensil has a global presence, including Europe, Asia, Africa, and North America.

Does Promensil work for hot flashes?