Horny goat weed, also known as yin yang huo in traditional Chinese medicine (TCM), is a plant indigenous to China, Japan and Korea.
Up to 15 different species of the Epimedium plant genus are used to source what is referred to as horny goat weed.
The most commonly used species are: Epimedium brevicornum, Epimedium sagittatum, Epimedium pubescens, Epimedium wushanense T. S. Ying and Epimedium koreanum Nakai.
These species of the Horny goat weed plant have been widely used in TCM for centuries to nourish the kidney and reinforce yang. Patterns associated with deficient yang include slowed metabolic processes, such as hypothyroidism, a dull ache in the lower back, soreness of the knees and weak lower limbs.
Social withdrawal, a tendency to easily catch colds, impotence, infertility, and loose morning stools are also indications of yang deficiency. Frequent urination and edema are also common signs of kidney yang deficiency. Within TCM, horny goat weed is administered (usually in combination with a number of other herbs) to treat these conditions.



- Inhibits PDE-5 enzyme & raises nitric oxide
- Boosts male & female libido
- Supports erectile function & performance
Horny Goat Weed Plant
Related Topics
Contemporary research into horny goat weed and its constituents is beginning to reveal a number of the plant’s characteristics.
However, it is important to note that there is not enough clinical evidence to confirm the use of horny goat weed for any particular condition, and the side effects are still not well understood within the Western medical tradition.
The plant’s active ingredient – icariin – is a flavonoid (antioxidant). Icariin is a PDE5 enzyme inhibitor similar to sildenafil, the main ingredient in Viagra. The word flavonoid means yellow in color in Latin.
The extract of horny goat weed is a brownish-yellow to a light-greenish-yellow color. The plant’s leaves and stems are used to make the supplement. This supplement is widely available. It comes in a powder, tablets, capsules, tinctures and is also made into a tea.
What is Horny Goat Weed Used For?
Horny goat weed is used to lower blood sugar levels. This supplement is used as a tonic for the reproductive system to boost libido (interest in sex) and to treat impotence (erectile dysfunction).
It is also used in the treatment lumbago (low back pain), arthritis, numbness and weakness of the limbs, hypertension and chronic bronchitis.
This supplement is considered an adaptogen tonic and is used to relieve fatigue by reducing levels of cortisol (stress hormone). This reduction helps restore normal metabolism, energy levels and libido.
When goats ate the leaves of this plant the frequency of copulation increased, leading to the name “horny goat weed”. The exact translation from the Chinese characters is “obscene goat leaves of pulse plants.”
Horny Goat Weed Sources
There are several specialist nurseries that carry medicinal Epimedium plants. The plant is harvested in the growing season and dried for later use.
Epimedium brevicornum produces a mass of small, round, heart-shaped leaflets with long spikes. The plant also produces small, star-shaped white flowers. Each of these flowers has a short spur with a hint of yellow at the center.
Epimedium sagittatum is a perennial that grows between 16 and 20 inches tall. The flowers are hermaphrodite (have both male and female organs) and are pollinated by bees. Each flower has four pointed triangular petals that are a pale pink color. This plant can grow in semi-shade (light woodland). It prefers dry or moist soil.
Epimedium wushanense T. S. Ying is an evergreen that reaches a height of between 20 and 45 inches and produces pale yellow flowers. These plants grow in forests, thickets, and crevices in Chongqing, Guangxi, Guixou, Hubei and Sichuan providences.
Epimedium pubescens is an evergreen perennial that grows in a clump-formation, producing glossy, dark-green oval leaves. The blossoms are loose panicles of tiny, white flowers that bloom in spring.
Epimedium koreanum Nakai is also used as a source for the supplement horny goat weed. It grows best in woodland shade or in the dry shade of trees. It is a shallow-rooted plant with rhizomes spreading just below the soil.
Horny Goat Weed Contraindications
Side effects of Epimedium may include dizziness, mood changes, nosebleeds and thirst. Horny goat weed may also cause irregular heartbeat, low blood pressure, upset stomach and dry mouth. High doses have been linked to spasms and respiratory failure.
Epimedium may interact with a number of prescription and over-the-counter medications, such as aspirin, blood thinners, oral contraceptives and antidepressants. It should also be avoid by those being treated for immune disorders or thyroid problems.
Horny goat weed may interact with medications that lower blood pressure or cholesterol. This supplement has been observed to slow blood clotting and may increase the risk of bleeding.
It is not recommended for use if pregnant or breastfeeding. It should also be avoided by those being treated for an estrogen-sensitive condition, such as breast or uterine cancer.
Be sure to speak with your doctor before taking horny goat weed to make sure the supplement is safe for you.
Horny goat weed is a decorative medicinal plant that is used in TCM for sexual dysfunction. The various species of Epimedium can be sourced from specialist nurseries.
- Natural Medicines. Horny Goat Weed: Professional Monograph. September 2015.
- Wu H1, Lien EJ, Lien LL. Chemical and pharmacological investigations of Epimedium species: a survey. Prog Drug Res. 2003;60:1-57.
- Zhang CZ, Wang SX, Zhang Y, Chen JP, Liang XM. In vitro estrogenic activities of Chinese medicinal plants traditionally used for the management of menopausal symptoms. J Ethnopharmacol. 2005 Apr 26;98(3):295-300.
Article last updated on: April 19th, 2018 by Nootriment