What Is Horny Goat Weed?

The Herb That Is Often Called a "Natural Viagra"

Horny goat weed tea, powder, capsules and tablets

Verywell / Anastasiia Tretiak

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Horny goat weed is a plant used in traditional Chinese medicine. As its nickname, "natural Viagra," implies, some people use horny goat weed to improve sexual function and arousal.

This article discusses the possible health benefits and side effects of taking horny goat weed. It also shares recommended doses and what to look for when buying this supplement.

Also Known As

  • Epimedium
  • Yin yan huo
  • Dâm dương hoắc

What Is Horny Goat Weed Used For?

The health and sexual benefit claims for horny goat weed go back thousands of years.

According to folklore, a Chinese goat herder noticed that his flock had heightened sexual activity after eating the plant. This led to the discovery of the plant's aphrodisiac (sexually stimulating) qualities. So, if you were wondering where this herbal remedy got its name, now you know.

Horny goat weed contains chemical compounds known as phytoestrogens, plant-based substances that have the same effects as the estrogen your body produces. This is why some people suggest that it can influence hormones and bone health.

Alternative medicine practitioners propose that horny goat weed is useful in complementary therapy to treat certain conditions.

These include:

Some claim that horny goat weed can improve circulation by thinning the blood. It has also been used to relieve symptoms of premenstrual syndrome (PMS), sharpen memory, and boost energy.

Few studies have looked at the benefits of horny goat weed. The main studies are in vitro (conducted in test tubes) or animal studies. Erectile dysfunction and bone disorders are the two most common conditions that have been studied.

Recap

Horny goat weed is sometimes used in alternative medicine. This herbal supplement may improve blood circulation and help treat bone diseases like osteoporosis and osteoarthritis.

Erectile Dysfunction

Quality research is lacking, but some evidence suggests horny goat weed can help males who have certain types of sexual dysfunction.

Horny goat weed contains a substance called icariin. Icariin can block a protein linked with erectile dysfunction called phosphodiesterase type 5 (PDE5).

PDE5 basically limits the increase in blood flow to the penis that is needed for an erection. Erectile dysfunction happens when there's not enough blood flowing to the penis.

Normally, the body curbs PDE5 levels. In people who have erectile dysfunction, PDE5 might not be controlled the way it should be.

Scientists found that icariin acts in the same way as Viagra (sildenafil) by blocking PDE5 activity. However, the action was weak, even in a test tube study. Compared to icariin, Viagra was 80 times more effective.

That’s not to say horny goat weed won't improve a man’s ability to have an erection. The supplement may increase blood flow enough to trigger an erection in people who have mild to moderate erectile dysfunction.

Bone and Joint Health

Phytoestrogens are plant-based estrogens found in horny goat weed and other plants. They can imitate the action of estrogen. Low estrogen levels after menopause can cause bone loss. Some alternative medicine practitioners suggest phytoestrogens can help treat this bone loss.

Scientists tested this theory in a 2007 study.

In the study, 85 late-postmenopausal women took either a placebo (sugar pill) or a phytoestrogen supplement extracted from horny goat weed. They all took 300 milligrams (mg) of calcium per day as well.

Two years later, horny goat weed extract appeared to help prevent bone loss. The phytoestrogen group had better bone turnover markers (the measure of how much new bone is being made to replace old bone tissue).

Horny goat weed wasn't linked with any negative effects that women experience when taking estrogen, such as endometrial hyperplasia (irregular thickening of the uterine wall). In some cases, endometrial hyperplasia can lead to cancer of the uterus.

Additionally, a 2018 animal study looked at the effects of icariin, the substance extracted from horny goat weed. They found that icariin can help slow the breakdown of cartilage in the joints that causes osteoarthritis.

Cartilage is a tissue that helps cushion the joints and prevents bones from rubbing together. When there's not enough cartilage to absorb shock, you may experience osteoarthritis symptoms like joint inflammation and stiffness.

Recap

Research found that the phytoestrogen in horny goat weed can help prevent bone loss in post-menopausal women. The women in the study also didn't experience any negative effects from the supplement.

Possible Side Effects

According to the National Institutes of Health (NIH), appropriate doses of horny goat weed are considered safe. High doses can be toxic to the kidneys and liver.

Talk to your healthcare provider before you use horny goat weed to treat any chronic condition. They can check to see if it would interact with any drugs you're taking, such as blood thinners or blood pressure medications.

Certain people shouldn't take horny goat weed:

  • Women who are pregnant or breastfeeding
  • People with bleeding disorders
  • Individuals with low blood pressure or irregular heartbeat
  • Women with hormone-sensitive conditions (endometriosis, uterine fibroids, and cancers of the breast, ovaries, or prostate)

Since horny goat weed can slow blood clotting, don't use it before surgery.

Horny goat weed capsules
Verywell / Anastasia Tretiak

Dosage and Preparation

You can find horny goat weed in many drug and health-food stores. It's available as a capsule, powder, tablet, or tea.

Some practitioners believe that an appropriate dose is 5 grams per day. However, more evidence is needed to recommend a specific dose.

Always check the label of any horny goat weed product you purchase. Similar varieties may have unwanted effects. Epimedium saggitatum and Epimedium grandiflorum are normally used in Chinese medicine.

What to Look For

Before taking this herbal supplement, talk to your healthcare provider. There are different variations of horny goat weed. Plus, not all of them are considered safe for all people. Your dosage and whether it's safe for you depends on several factors. These include your age, sex, and medical conditions.

If you do choose to take this supplement, the NIH recommends looking for a Supplement Facts label on the product you buy. This label contains important information, such as the amount of active ingredients per serving. It will also list other ingredients that may affect your health.

Look for a product that contains a seal of approval from a third-party organization that provides quality testing. These organizations include U.S. Pharmacopeia, ConsumerLab.com, and NSF International.

A seal of approval from one of these organizations doesn't guarantee that the product is safe or effective. But it does assure you that it was properly made, contains the ingredients listed on the label, and doesn't have harmful levels of contaminants.

Summary

Horny goat weed is an herbal supplement that some people use to treat erectile dysfunction and stimulate sexual arousal. Some research suggests it has other positive effects, especially on bone health.

People who have certain conditions shouldn't take this supplement. Talk with your healthcare provider to determine if it's right for you.

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8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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