What Is Pueraria mirifica?

Pueraria mirifica is the scientific name for a specific species that belongs to a genus or group of plants called Pueraria. In particular, P. mirifica is a plant that's native to Thailand. In Thailand, this herb is called kwao kruea khao.

The potentially medicinal plants of the Pueraria group—like P. mirifica—have isoflavones. This group of plants is thought to work through these bioactive plant chemicals, which may have estrogen-like activity. For this reason, isoflavones are also called phytoestrogens.

This article discusses what you should know about P. mirifica—its potential uses, side effects, and interactions.

Uses of Pueraria mirifica

Like many medicinal plants, people may use P. mirifica for many reasons. However, several studies have assessed P. mirifica for the following potential uses.

Menopause

In a review, results from several small studies suggested that P. mirifica helped menopausal symptoms.

For example, a small 24-week study assessed P. mirifica at three different doses, which were 20, 30, or 50 milligrams (mg) daily. Compared to a placebo (a substance with no medication), P. mirifica at any dose decreased symptoms of vaginal dryness and painful sex. People in the study who were postmenopausal and took P. mirifica also seemed to have improved vaginal atrophy (wasting), which is a condition of a thinning or inflamed (swollen) vagina.

In a small clinical trial, 50 or 100 milligrams of P. mirifica daily relieved menopausal symptoms, such as hot flashes and night sweats. While this clinical trial followed study participants for six months, there was no placebo group.

Another small clinical trial assessed a daily 50-milligram dose of P. mirifica compared to a control group taking a daily dose of 0.625 milligrams of conjugated equine estrogen (CEE)—like Premarin—with or without medroxyprogesterone (MPA) 2.5 milligrams. MPA is used if the control group study participant still has a uterus (womb). At six months, the P. mirifica group appears to have relieved menopausal symptoms—like hot flashes and night sweats—as well as the control group.

Another small study compared a P. mirifica vaginal, topical product to conjugated equine estrogen (CEE) cream—like Premarin Vaginal. At 12 weeks, the CEE vaginal cream was more effective than the P. mirifica vaginal, topical product at improving vaginal atrophy. But similar to CEE vaginal cream, the P. mirifica vaginal, topical product significantly relieved vaginal-related symptoms of menopause, such as vaginal dryness and painful sex.

While these studies seem promising, larger and well-designed clinical trials are still needed.

Bone Health

Many people assigned female at birth tend to experience menopause between 45 to 55 years of age. While this might be normal, the decrease in estrogen levels may speed up bone loss.

According to a review, P. mirifica might be able to help with bone health during menopause. In a small clinical trial with postmenopausal study participants, 20, 30, or 50 milligrams of P. mirifica daily were compared to a placebo. After six months of treatment, P. mirifica was linked to lower bone-specific alkaline phosphatase (AP) levels. High bone-specific AP levels are typically connected to bone problems, like a high bone turnover rate.

While this was a six-month clinical trial, larger, well-designed studies are still necessary to confirm these results.

High Cholesterol

A review suggested P. mirifica affected cholesterol in postmenopausal women with dyslipidemia (abnormal cholesterol levels).

In a small clinical trial, study participants took either a placebo product or 50 milligrams of P. mirifica root powder tablets twice daily. After two months of treatment, P. mirifica was linked to reduced low-density lipoprotein ("bad cholesterol") and improved high-density lipoprotein ("good cholesterol") levels. But in the above "bone health" clinical trial, P. mirifica also increased triglycerides.

Similar to P. mirifica's other potential uses, further research with larger, well-designed studies is still needed.

What Are the Side Effects of Pueraria mirifica?

Like many medications and herbs, side effects are possible with P. mirifica.

Common Side Effects

There were only a few human studies on P. mirifica. So, well-designed and long-term clinical trials are still needed to appropriately assess P. mirifica's safety.

However, side effects might be mild and common side effects may include:

• Bloatedness
• Dizziness
• Hand Itchiness
• Muscle aches and pain
• Nausea or vomiting
• Sleeping problems
• Stomach cramps
• Tiredness
• Vaginal bleeding or spotting

Severe Side Effects

P. mirifica may have other possible severe side effects that may include:

• Anemia: In a small clinical trial, only one out of 30 study participants taking P. mirifica had anemia. It is unclear if this was a direct side effect of taking P. mirifica. However, symptoms may typically include severe tiredness, shortness of breath, and chest pain.
• Breast pain: Four out of 30 study participants taking P. mirifica had breast pain. The clinical trial didn't have severity details about this side effect, but it's a possible symptom of breast cancer.
• Chest discomfort: Only two out of 30 participants in the P. mirifica group experienced chest discomfort. It is unclear if this was a direct side effect of taking P. mirifica. Again, the study didn't mention the severity of this side effect. But it may be a severe symptom of a life-threatening condition—like a heart attack.
• Palpitations: Similar to chest discomfort, two out of 30 participants in the P. mirifica group reported palpitations. It is unclear if this was a direct side effect of taking P. mirifica. And even though the study didn't have details about the severity of this side effect, palpitations might be a severe symptom of an abnormal heart rhythm condition.

Severe allergic reaction is another serious side effect possible with any medication. Symptoms may include breathing difficulties, itchiness, and rash. 

Call 911 and get medical help immediately if you're having a severe allergic reaction or any of your symptoms feel life-threatening.

Precautions

Your healthcare provider may advise against using P. mirifica if any of the following applies to you:

• Severe allergic reaction: If you have a severe allergic reaction to P. mirifica or its components (ingredients), you shouldn't take this medication.
• Breast cancer: Based on a review, P. mirifica treatment didn't seem to affect the breast tissue of study participants in a small study. But more research is needed. What's more, the isoflavones of P. mirifica may have estrogen-like activity. So, similar to red clover, this herb may interfere with endocrine (hormone) therapy. Endocrine therapy is typically used after surgery to prevent certain breast cancer types from returning.
• Pregnancy or breastfeeding: With only a few human studies available, assessing P. mirifica's safety is challenging without long-term and well-designed clinical trials. Moreover, P. mirifica doesn't seem to have any product labels targeting pregnant or breastfeeding parents. In general, caution is typically recommended. To discuss the benefits and risks of P. mirifica in pregnancy or breastfeeding, reach out to your healthcare provider.
• Children: There are only a few human clinical trials. For this reason, it isn't easy to evaluate P. mirifica's safety without long-term and well-designed clinical trials. What's more, most P. mirifica products are likely for adults. So, use it with caution. If you're considering P. mirifica for your child, have a conversation with your child's healthcare provider (pediatrician) first.
• Older adults: While older adults may have participated in some clinical trials, some of the study participants were only postmenopausal women. Moreover, some older adults may be more sensitive to medication side effects. For this reason, take P. mirifica with caution.
  

Dosage: How Much Pueraria mirifica Should I Take?

Doses may vary based on the specific dosage form and your individual needs.

If you want to give P. mirifica a try, talk with your healthcare provider first. And follow their recommendations or the label instructions.

There are a limited number of human studies on P. mirifica. And long-term and well-designed studies are still needed. For this reason, there are no guidelines on the appropriate dosage to take P. mirifica for any condition.

But in general, people may take P. mirifica up to 50 and 100 milligrams (mg) capsules by mouth once daily. Another potential option is to take 50 milligrams of P. mirifica root powder tablets twice daily.

In a small study, 0.5 grams (g) of a P. mirifica topical product was also inserted into the vagina daily for two weeks before decreasing to 0.5 grams three times weekly for ten weeks.

What Happens If I Take Too Much Pueraria mirifica?

With only a few human studies available, long-term and well-designed studies are still needed to appropriately assess P. mirifica's safety, including toxicity and overdoses. But in rats, P. mirifica affected how the reproductive system works. However, after stopping treatment, this effect was reversible within one week for male rats and two weeks for female rats.

If you think you're experiencing an overdose or life-threatening symptoms, get medical help immediately.

Interactions

Use caution when taking P. mirifica with the following:

• Blood thinners: P. mirifica may result in vaginal bleeding or spotting. For this reason, taking P. mirifica with blood thinners—like Coumadin (warfarin) may worsen the side effects of severe bleeding and bruising.
• Cholesterol medications: P. mirifica may lower your cholesterol. This may have additive effects or increase the side effects of your cholesterol-lowering medications, such as Lipitor (atorvastatin).
• Hormone therapy: P. mirifica contains isoflavones that may have some estrogen-like activity. So, similar to red clover, P. mirifica may interact with endocrine (hormone) therapy for certain types of breast cancer, menopausal hormone therapy, and hormonal birth control.

It is essential to carefully read a supplement's ingredient list and nutrition facts panel to know which ingredients and how much of each ingredient is included. Please review this supplement label with your healthcare provider to discuss potential interactions with foods, other supplements, and medications.

How to Store Pueraria mirifica

Since storage instructions may vary for different herbal products, carefully read the directions and packaging label on the container. But in general, keep your medications tightly closed and out of the reach of children and pets, ideally locked in a cabinet or closet. Try to store your medications in a cool and dry place.

Discard after one year or as indicated on the packaging. Avoid pouring unused and expired medicines down the drain or in the toilet. Visit the FDA's website to know where and how to discard all unused and expired medicines. You can also find disposal boxes in your area.

Ask your pharmacist or healthcare provider if you have any questions about the best ways to dispose of your medications or supplements.

Similar Supplements

Other herbs, supplements, and foods may have hormonal effects, including black cohosh, red clover, and soy products.

Niacin has been used to lower cholesterol levels. Eating a fiber-rich, anti-inflammatory diet has also been linked to lowered cholesterol levels. Fiber supplements have also been used to decrease cholesterol.

In general, the Pueraria genus is a group of plants that consists of 26 different species, with a primary bioactive chemical likely being isoflavones. A few small studies in a review suggested P. lobata may be most similar to P. mirifica—with P. lobata's potential effects on lowering low-density lipoprotein ("bad cholesterol").

But like P. mirifica, P. lobata requires large and well-designed human clinical trials to study its potential uses.

Sources of Pueraria mirifica & What to Look For

There are several dfferent sources of P. mirifica.

Food Sources of Pueraria mirifica

P. mirifica is naturally available as a plant in the legume family, which also contains beans and peas.

In general, dietary changes may interact with your medications or affect your medical conditions. For this reason, talk with your healthcare provider first. They will help you safely make any dietary changes.

Pueraria mirifica Supplements

P. mirifica is available in various forms, including capsules, tablets, and powder. There are also vegan and vegetarian options. A small study suggested there may also be topical product versions of P. mirifica.

The specific product you choose will depend on your preference and what you hope to get in terms of effects. Each product may work a bit differently, depending on the form. So, following your healthcare provider's recommendations or label directions is essential.

Summary

P. mirifica is a plant from the legume family along with peas and beans. This herb may have some potential uses for menopause, bone health, and high cholesterol.

There are a limited number of human studies. For this reason, take P. mirifica with caution. Side effects and medication interactions are possible.

More research with larger and well-designed clinical trials is still needed to study P. mirifica's effectiveness and safety. Before taking P. mirifica, reach out to your pharmacist or healthcare provider to help you safely achieve your health goals.