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Horny Goat Weed

Also known as: Yinyanghuo, Fairy Wings, Rowdy Lamb Herb, Epimedium, Herba Epimedii, Barrenwort, Bishop's Hat

Overview

Horny goat weed is the common name for the plant known as Epimedium, which is used in traditional Chinese herbal medicine as a tonic, an aphrodisiac, and an antirheumatic agent. It also goes by the names Herba epimdii, yin yang huo, fairy wings, and rowdy lamb herb. While over 200 compounds have been identified in horny goat weed, the main bioactive constituents appear to be flavonoids, of which icariin is the most well-studied. Icariin is also the main active ingredient in horny goat weed supplements.

Benefits

Horny goat weed might benefit ED through its inhibition of phosphodiesterase-5 (PDE-5). This is the same mechanism exerted by pharmaceuticals like Viagra. PDE-5 inhibition increases levels of cyclic GMP, which enhances smooth muscle relaxation and blood flow to the penis and promotes erection. Horny goat weed may also increase the activity of nitric oxide synthase enzymes and elevate the production of nitric oxide, which also promotes smooth muscle relaxation. The potential cardioprotective qualities of horny goat weed may be related to a decrease in vascular smooth muscle cell proliferation, reduced platelet activation, lipid modulation, and improvements in endothelial function. The suspected neuroprotective mechanisms of horny goat weed could include the upregulation of antioxidant activity and the inhibition of inflammation and oxidative stress in the brain.

How it works

Although horny goat weed is one of the most common ingredients in male testosterone-boosting and erectile dysfunction (ED) supplements, there is a lack of human evidence to support its effectiveness for these outcomes. Horny goat weed (icariin) does have pro-erectile properties in rodent models of ED. One study found that horny goat weed elevated estrogen and reduced cholesterol and triglyceride levels in postmenopausal women. Some studies showed that horny goat weed appears to improve bone mineral density (BMD) and pain intensity in people with osteoporosis, both in combination with standard use medications and as an alternative treatment. In vitro and in vivo studies have suggested that horny goat weed is useful for treating cardiovascular diseases, including atherosclerosis and coronary heart disease. Furthermore, recent evidence supports the neuroprotective properties of horny goat weed, though human studies are needed to confirm these effects.

Side effects

Testosterone boosting effects in rats have been noted at a dosage of 200mg/kg of a 40% extract (80mg/kg Icariin), and based on body weight conversions from rats to humans this results in an estimated human dose of: 900mg Icariin for a 150lb person, 1,200mg Icariin for a 200lb person, 1,500mg Icariin for a 250lb person. Studies that use a lower dosage of Icariin (1-10mg/kg) are approximately equal to: 11-110mg Icariin for a 150lb person, 15-150mg Icariin for a 200lb person, 18-180mg Icariin for a 250lb person. The human study on postmenopausal women and bone health noted that 60mg Icariin daily was active, and might serve as the lowest active dose currently known. It also appears to fall within the above range of lower active dosages which show benefits in rats.

Dosage

Horny goat weed appears to be safe and well-tolerated when taken orally, and only minor side effects, including abdominal discomfort and nausea, have been observed. In some cases, abnormal heart rhythms and skin rashes have been reported, but in both instances, horny goat weed was coingested with other herbal supplements or pharmaceuticals. Since horny goat weed may have antihypertensive and anticoagulation effects in the body, taking it alongside medications that reduce blood pressure or prevent blood clotting may cause unwanted side effects. Horny goat weed may also increase estrogen in women. In vitro, icariin and some of its metabolites have demonstrated inhibitory effects on specific isoforms of UDP-glucuronosyltransferase in the gastrointestinal tract. These enzymes play a crucial role in the metabolism of orally administered drugs like opioids, naproxen, acetaminophen, and amitriptyline by facilitating their first-pass metabolic clearance. In vivo studies are required to assess the inhibitory effect of icariin’s metabolites on UGT enzymes in human participants, and to understand the potential herb-drug interactions that may occur when icariin is taken alongside medications.

FAQs

What is horny goat weed?

Horny goat weed is the common name for the plant known as Epimedium, which is used in traditional Chinese herbal medicine as a tonic, an aphrodisiac, and an antirheumatic agent. It also goes by the names Herba epimdii, yin yang huo, fairy wings, and rowdy lamb herb. While over 200 compounds have been identified in horny goat weed, the main bioactive constituents appear to be flavonoids, of which icariin is the most well-studied. Icariin is also the main active ingredient in horny goat weed supplements. Horny goat weed appears to have anti-atherogenic, anti-inflammatory, antiviral, and immune-modulating effects, though most of these mechanisms have only been investigated in research animals and in vitro.

What are horny goat weed’s main benefits?

Although horny goat weed is one of the most common ingredients in male testosterone-boosting and erectile dysfunction (ED) supplements, there is a lack of human evidence to support its effectiveness for these outcomes. Horny goat weed (icariin) does have pro-erectile properties in rodent models of ED. One study found that horny goat weed elevated estrogen and reduced cholesterol and triglyceride levels in postmenopausal women. Some studies showed that horny goat weed appears to improve bone mineral density (BMD) and pain intensity in people with osteoporosis, both in combination with standard use medications and as an alternative treatment. In vitro and in vivo studies have suggested that horny goat weed is useful for treating cardiovascular diseases, including atherosclerosis and coronary heart disease. Furthermore, recent evidence supports the neuroprotective properties of horny goat weed, though human studies are needed to confirm these effects.

What are horny goat weed’s main drawbacks?

Horny goat weed appears to be safe and well-tolerated when taken orally, and only minor side effects, including abdominal discomfort and nausea, have been observed. In some cases, abnormal heart rhythms and skin rashes have been reported, but in both instances, horny goat weed was coingested with other herbal supplements or pharmaceuticals. Since horny goat weed may have antihypertensive and anticoagulation effects in the body, taking it alongside medications that reduce blood pressure or prevent blood clotting may cause unwanted side effects. Horny goat weed may also increase estrogen in women. In vitro, icariin and some of its metabolites have demonstrated inhibitory effects on specific isoforms of UDP-glucuronosyltransferase in the gastrointestinal tract. These enzymes play a crucial role in the metabolism of orally administered drugs like opioids, naproxen, acetaminophen, and amitriptyline by facilitating their first-pass metabolic clearance. In vivo studies are required to assess the inhibitory effect of icariin’s metabolites on UGT enzymes in human participants, and to understand the potential herb-drug interactions that may occur when icariin is taken alongside medications.

How does horny goat weed work?

Horny goat weed might benefit ED through its inhibition of phosphodiesterase-5 (PDE-5). This is the same mechanism exerted by pharmaceuticals like Viagra. PDE-5 inhibition increases levels of cyclic GMP, which enhances smooth muscle relaxation and blood flow to the penis and promotes erection. Horny goat weed may also increase the activity of nitric oxide synthase enzymes and elevate the production of nitric oxide, which also promotes smooth muscle relaxation. The potential cardioprotective qualities of horny goat weed may be related to a decrease in vascular smooth muscle cell proliferation, reduced platelet activation, lipid modulation, and improvements in endothelial function. The suspected neuroprotective mechanisms of horny goat weed could include the upregulation of antioxidant activity and the inhibition of inflammation and oxidative stress in the brain.

Supplements Containing Horny Goat Weed

Viper by Vitamin World
45

Viper

Vitamin World

Score: 45/100
Staminol by GNC Men's
45

Staminol

GNC Men's

Score: 45/100
Re-Forge by GNC Beyond Raw
40

Re-Forge

GNC Beyond Raw

Score: 40/100
Test by Royal Sport
78

Test

Royal Sport

Score: 78/100