Epimedium: Nature’s Alternative to the “Little Blue Pill”
The well-known Chinese medicinal herb yin yang huo (scientific name Epimedium) is also known popularly as “horny goat weed,” “rowdy lamb herb,” and “bishop’s hat.” It was likely first used in traditional Chinese medicine (TCM) as a natural aphrodisiac 2000 years ago [1,2].
This hardy, heart-shaped plant can be found growing in the wild in Asia, including in China, and in Europe. It may have gotten its name when herders noticed that their goats became more sexually active after grazing on Epimedium plants.
In a natural progression from animals to humans, Epimedium has been used for centuries in TCM to help counter fatigue and sexual dysfunction (including erectile dysfunction), and boost both male and female libido.
Modern science has confirmed these properties of Epimedium, along with its newly discovered ability to protect nerve cells and promote their growth, lower atherosclerosis risk, reduce inflammation, and perhaps even slow down aging. More on each of these below.
Over the past few years researchers have isolated more than 260 biologically potent compounds from this versatile plant, including its main flavonoid component icariin, along with other flavonoids, polysaccharides, and sterols.
Let’s take a closer look at some of the compelling evidence for Epimedium’s proposed biological actions when it comes to sexual potency.
The Main Types of Erectile Dysfunction
Erectile dysfunction (ED) is estimated to affect around 20 million men in the U.S., and can be categorized either as primary ED – a rare condition in which a man may never have been able to sustain an erection – or secondary ED, typically caused by stroke, diabetes, or an injury.
Additionally, medications for high blood pressure, depression, high cholesterol, cancer, and long-term pain have been known to cause ED or contribute to it.
Scientific Research Into Solutions for ED
In a 2007 laboratory study, consumption of Epimedium extract was seen to help improve erectile function in aged male rats . In separate studies, Epimedium’s main active component icariin, while helping to boost erectile potency, did not have much of an effect on testosterone levels [4-6].
Exciting new research suggests that Epimedium might be just as effective for male libido as the well-known “little blue pill” – but with fewer side-effects.
For instance, in 2008, researchers from the University of Milan in Italy tested four plants which are used as natural aphrodisiacs in traditional cultures, along with three individual compounds [7,8].
The blue pill works by blocking the actions of an enzyme known as phosphodiesterase-5, or PDE5, which helps to control blood flow to the penis. In short, suppressing PDE5’s activity promotes male erections .
Icariin Is a Compound in Epimedium
In the Italian study, of the four plants tested, only Epimedium and its main active component icariin were able to block PDE5. Next, the study researchers created six chemically modified versions of icariin, which they also tested on PDE5. The most efficient of these, compound 5, apparently works just as well as the blue pill – and is likely to cause fewer side effects.
This is because the active ingredient in the blue pill also affects phosphodiesterase enzymes (PDEs) other than PDE5 and can therefore harm vision and heart function. Compound 5 is very specific in that it only blocks PDE5. Indeed, icariin has been shown to have up to 100-fold specificity for PDE5 relative to other PDEs . Therefore, it is unlikely to affect other organs like the active ingredient in the blue pill does.
Along with inhibiting PDE5’s actions, icariin at low doses also induces the enzyme nitric oxide synthase, likely leading to increased production of the gaseous compound nitric oxide (NO) – which is known to dilate blood vessels and improve local blood flow . This may also help to improve erectile function.
Protecting Nerve Cells and Promoting their Growth
Icariin has been shown to have neuroprotective and neuroregenerative properties in multiple studies [12-18].
For instance, in a 2013 laboratory study, Epimedium extract and icariin were seen to help promote the recovery of damaged nerves and improve their re-growth relative to both icariin and control, although icariin was better than control [19,20].
Further, flavonoid compounds from Epimedium have been shown to promote the proliferation and differentiation of neural stem cells in laboratory experiments, suggesting that these compounds may promote neuronal growth .
Icariin appears to protect brain cells – known scientifically as neurons – by inhibiting pro-oxidant and pro-inflammatory markers in response to stress [22,23].
In a laboratory mouse model with an early onset and rapid advancement of senescence, or aging, icariin treatment for 15 weeks was seen to prevent aging-related learning and memory losses via various mechanisms, including the prevention of oxidative damage .
Intriguingly, icariin and its derivatives have been shown to extend lifespan and maintain DNA stability in nematode worms known as C. elegans as well as in mice [25,26]. Indeed, there is some preliminary evidence to suggest that icariin may be useful in treating age-related diseases .
Lowering Atherosclerosis Risk
Atherosclerosis is a disease in which plaque builds up inside the arteries. Emerging evidence suggests that icariin can protect against DNA damage, correct defects in the cells lining blood vessels, prevent the proliferation and migration of smooth muscle cells, suppress inflammatory responses, and prevent platelet activation. Together, these actions appear to contribute to icariin’s ability to lower atherosclerosis risk .
Laboratory studies show that icariin can limit the extent of inflammation in lung and immune cells, as well as in a rat model of asthma [29-31].
Epimedium: Side Effects
Side effects associated with Epimedium consumption appear to be caused by taking high doses of the herb for prolonged periods of time. These can include spasms, breathing problems, sweating, reduced thyroid function, irritability and aggression, nausea, a racing heart, and feeling hot [32,33].
In one instance, a patient reported rash, pain, and a burning sensation after taking Epimedium with ginkgo, while another patient with congestive heart failure was hospitalized with symptoms of shortness of breath, chest pain, and irregular heartbeat.
Epimedium may affect hormone levels, especially estrogen, and should be completely avoided by patients with hormone-sensitive cancers or with heart disease .
Organic epimedium is an ingredient in T-Plexx by Organixx, a comprehensive formula uniquely designed to support healthy testosterone levels in men.
 NCBINCBI Logo Skip to main content Skip to navigation Resources How To About NCBI Accesskeys PubMed US National Library of Medicine National Institutes of Health Search databaseSearch term Search AdvancedHelp Result Filters Format: AbstractSend to Neurol Res. 2010 Sep;32(7):736-42. doi: 10.1179/174313209X459183. Epub 2009 Aug 21. Effects of Epimedium flavonoids on proliferation and differentiation of neural stem cells in vitro.