Horny Goat Weed: Overview, Uses, Side Effects, Precautions, Interactions, Dosing and Reviews

Overview

Horny goat weed refers to various herb species of the Epimedium genus, and may be known as "yin yang huo." It has limited evidence of health benefits.

Horny goat weed contains chemicals that might help increase blood flow and improve sexual function. It also contains phytoestrogens, chemicals that act somewhat like the hormone estrogen.

People use horny goat weed for erectile dysfunction (ED), sexual problems, weak and brittle bones, health problems after menopause, and other conditions, but there is no good scientific evidence to support any of these uses.

Uses & Effectiveness

Insufficient Evidence for

Weak and brittle bones (osteoporosis). Taking a specific extract of horny goat weed for 24 months in combination with calcium supplements decreases bone loss of the spine and hip in women who have passed menopause better than taking calcium alone. Chemicals in the extract act somewhat like the hormone estrogen.
Health problems after menopause. Taking horny goat weed water extract for 6 months can decrease cholesterol and increase estrogen levels in postmenopausal women.
Bronchitis.
Ejaculation problems.
Erectile dysfunction (ED).
Fatigue.
Heart disease.
High blood pressure.
HIV/AIDS.
Joint pain.
Liver disease.
Memory loss.
Sexual problems.
Other conditions.

More evidence is needed to rate horny goat weed for these uses.

Side Effects

When taken by mouth: Horny goat weed extract is possibly safe when used short-term. A specific extract of horny goat weed containing phytoestrogens has been taken by mouth safely for up to 2 years. Another extract containing a chemical called icariin has been taken safely for up to 6 months.

But some types of horny goat weed are possibly unsafe when used for a long period of time or in high doses. Serious side effects including severe breathing problems have been reported.

Special Precautions and Warnings

Pregnancy: Horny goat weed is possibly unsafe when taken by mouth during pregnancy. It might harm the developing fetus. Avoid using it.

Breast-feeding: There isn't enough reliable information to know if horny goat weed is safe to use when breast-feeding. Stay on the safe side and avoid use.

Bleeding disorders: Horny goat weed might slow blood clotting. This might increase the risk of bleeding. Taking horny goat weed might make bleeding disorders worse.

Hormone sensitive cancers and conditions: Horny goat weed acts like estrogen and can increase estrogen levels in some people. Horny goat weed might worsen some estrogen-sensitive conditions, such as breast and uterine cancer.

Surgery: Horny goat weed might slow blood clotting. This might increase the risk of bleeding during surgery. Stop taking horny goat weed at least 2 weeks before surgery.

Interactions

Moderate Interaction

Be cautious with this combination

Medications for high blood pressure (Antihypertensive drugs) interacts with Horny Goat Weed
Horny goat weed might lower blood pressure. Taking horny goat weed along with medications that lower blood pressure might cause blood pressure to go too low. Monitor your blood pressure closely.
Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs) interacts with Horny Goat Weed
Horny goat weed might slow blood clotting. Taking horny goat weed along with medications that also slow blood clotting might increase the risk of bruising and bleeding.
Estrogens interacts with Horny Goat Weed
Horny goat weed might have some of the same effects as estrogen and might increase blood levels of estrogen in some people. Taking horny goat weed with estrogen might increase the effects and side effects of estrogen.
Medications changed by the liver (Cytochrome P450 1A2 (CYP1A2) substrates) interacts with Horny Goat Weed
Some medications are changed and broken down by the liver. Horny goat weed might change how quickly the liver breaks down these medications. This could change the effects and side effects of these medications.
Medications changed by the liver (Cytochrome P450 2B6 (CYP2B6) substrates) interacts with Horny Goat Weed
Some medications are changed and broken down by the liver. Horny goat weed might change how quickly the liver breaks down these medications. This could change the effects and side effects of these medications.
Medications changed by the liver (Cytochrome P450 3A4 (CYP3A4) substrates) interacts with Horny Goat Weed
Some medications are changed and broken down by the liver. Horny goat weed might change how quickly the liver breaks down these medications. This could change the effects and side effects of these medications.

Dosing

There isn't enough reliable information to know what an appropriate dose of horny goat weed might be. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult a healthcare professional before using.

View References

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CONDITIONS OF USE AND IMPORTANT INFORMATION: This information is meant to supplement, not replace advice from your doctor or healthcare provider and is not meant to cover all possible uses, precautions, interactions or adverse effects. This information may not fit your specific health circumstances. Never delay or disregard seeking professional medical advice from your doctor or other qualified health care provider because of something you have read on WebMD. You should always speak with your doctor or health care professional before you start, stop, or change any prescribed part of your health care plan or treatment and to determine what course of therapy is right for you.

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Horny Goat Weed - Uses, Side Effects, and More

Overview

Uses & Effectiveness

Insufficient Evidence for

Side Effects

Special Precautions and Warnings

Interactions

Moderate Interaction

Medications for high blood pressure (Antihypertensive drugs) interacts with Horny Goat Weed

Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs) interacts with Horny Goat Weed

Estrogens interacts with Horny Goat Weed

Medications changed by the liver (Cytochrome P450 1A2 (CYP1A2) substrates) interacts with Horny Goat Weed

Medications changed by the liver (Cytochrome P450 2B6 (CYP2B6) substrates) interacts with Horny Goat Weed

Medications changed by the liver (Cytochrome P450 3A4 (CYP3A4) substrates) interacts with Horny Goat Weed

Dosing