What Is Horny Goat Weed & Does It Actually Work?

There's a somewhat mystical-sounding herb used in traditional Chinese medicine that claims to boost your libido and even help treat erectile dysfunction. It's called epimedium, Barrenwort, or "horny goat weed," and the story behind the name is as funny as it sounds.

Legend has it, an ancient Chinese medicine doctor named Tao Jing Hong was passing through a village when he heard people talking about a magical herb that was making goats have sex all the time, says Jingduan Yang, MD, a board-certified psychiatrist and founding medical director of Tao Integrative Medicine in Philadelphia. "So, the goats looked horny all the time, and that's where the name comes from," Dr. Yang says.

Horny goat weed is actually an herb of a flowering plant in the berry family, and it's one of the many herbs used in traditional Chinese medicine, Dr. Yang says. But in order to understand how horny goat weed works, it can be helpful to have a grasp on how herbs are used in general. In traditional Chinese medicine, herbs aren't really classified as chemical agents, and instead are used as "energetic agents," Dr. Yang says. It's not always clear exactly what the mechanisms are; it's a little more theoretical.

So, how does horny goat weed work according to traditional Chinese medicine? "When you take this horny goat weed, it's transformed into warming energy, which travels to the liver and kidney," he says. The warmth of a person's kidney energy is believed to correlate with their sexual energy and drive. "Horny goat weed definitely has been used to enhance the sexual performance and reproductivity, because of its impact on kidney energy," Dr. Yang says. "That's the mechanism from the Chinese medicine perspective."

As far as modern medicine goes, researchers are also curious about what horny goat weed does to the body. It is thought to enhance blood flow throughout the body and help with inflammation, especially in joints, says Aleece Fosnight, MSPAS, PA-C, a urology physician's assistant. "Its mechanism of action is thought to be similar to Viagra or Cialis," she says: It might boost blood flow to the penis or clitoris, which could increase arousal.

Some researchers have extracted the chemical ingredients from horny goat weed and injected them into the penis of animals to see what it does, Dr. Yang says. "It does seem to inhibit one of the enzymes that tends to reduce or restrict the blood flow, therefore, increasing the blood flow in the penis," he says. There haven't been enough human-based clinical trials to prove that it works, so the FDA doesn't recommend using horny goat weed, Fosnight says. So as with most medicinal herbs or supplements, it's important to talk to your doctor before trying this one on yourself.

If horny goat weed is taken outside of a physician's recommendation, it can cause some serious issues, from dry mouth to low blood pressure, down the line. "The problem today is that people are using Chinese herbs as if they are food, or as if they are just like vitamins," Dr. Yang says, "which is a problem, because Chinese herbal medicine is not food." Even though you can buy supplements in pill or powder form, you shouldn't take them without talking to an expert first, suggests the National Centre for Complementary and Integrative Health (NCCIH) — and also common sense.

Traditional Chinese medicine is all about balance, so horny goat weed is recommended along with dozens of other herbs that work together. "You don’t just use one thing to supplement the energy and then tip off the imbalance of the other energy," Dr. Yang says.

In combination with certain medications — blood thinners, aspirin, oral contraceptives, antidepressants, thyroid medications, blood pressure medications, and nitroglycerin, for example — Fosnight says horny goat weed can cause a dangerous drop in blood pressure. Not to mention, there have been reports of some Chinese herbal products being contaminated with drugs, toxins, or heavy metals, according to the NCCIH. So you don't necessarily know what's going into the herbs that you get.

You might have come across horny goat weed as an ingredient in some personal lubricants, but Fosnight says that you might want to save your pennies there. "There may be a small increase in blood flow to the genitals when applied topically, however the blood flow needs to be internally for both men and women to get the most benefit of arousal," she says. According to Dr. Yang, "The body has an ability to absorb or interact with a form of energy through the skin." In that case, horny goat weed might work when applied topically, at least from an "energetic" perspective.

At the end of the day, you'll want to talk to your healthcare provider before going the way of the goat. These herbs may not be the answer to your sexual-health prayers — even if they did work on a goat.