Herbal Supplements

For centuries, herbal supplements have been used for their healing properties. Before you take herbals, make sure you know what's in them, if they're safe, and how they react with other supplements and medications.

What are herbal supplements?

Herbal supplements are products derived from plants and/or their oils, roots, seeds, berries or flowers. Herbal supplements have been used for many centuries. They are believed to have healing properties.


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What are the forms of herbal supplements?

Herbal products come in many different forms and may be used internally or externally. The forms of herbal products include:

  • Liquid extracts.
  • Teas.
  • Tablets and capsules.
  • Bath salts.
  • Oils.
  • Ointments.

What are some common herbal supplements and their uses?

There are many herbal supplements that have several different uses. The following are some of the most common:

Aloe Vera: used topically for burns, psoriasis and osteoarthritis. Used in the oral form for digestive issues such as gastritis or constipation.

Black cohosh: used to treat hot flashes, night sweats, vaginal dryness and menopausal symptoms.

Chamomile: used to treat sleeplessness, anxiety, upset stomach, gas and diarrhea. It is also used topically for skin conditions. Caution in people with ragweed allergy.

Echinacea: used to fight cold and flu symptoms.

Flaxseed: used to lower cholesterol. Good source of fiber and omega-3 fatty acids.

Ginko: used to treat memory problems and tinnitus (ringing in the ears). Can be used along with the antidepressant selective serotonin reuptake inhibitors (SSRIs) to enhance sex drive and sexual performance in people who have side effects with antidepressant medications. Caution in people taking blood thinners.

Peppermint oil: used to treat digestion problems such as nausea, indigestion, stomach problems and bowel conditions.

Soy: used to treat menopausal symptoms, memory problems and high cholesterol levels. Organic, whole soy food is preferable to soy supplements and processed soy foods like soy hot dogs.

St. John’s Wort: used to treat depression, anxiety and sleep disorders. NOTE: This herb has many other drug and herb interactions. Consult your healthcare provider before starting this supplement.

Tea tree oil: used topically to treat several conditions including, acne, athlete's foot, nail fungus, wounds, infections, lice, oral yeast infection (thrush), cold sores and dandruff.


How popular are herbal supplements?

Herbal supplements are widely used in the United States. A study by the Centers for Disease Control states that more than half of the people in the country take a daily herbal supplement.

Are herbal supplements safe to use?

The Dietary Supplement Health Education Act of October 1994 does not require manufacturers of herbal products to prove that their products are either safe or effective before they are put on the market. However, the Food and Drug Administration (FDA) is responsible for monitoring the safety of a product after it has become available to consumers.

In many cases, people use herbal supplements with prescribed medicines. This can result in serious health problems due to drug interactions. Always talk to your healthcare provider before you begin using an herbal supplement.

If you take aspirin, digoxin, diuretics, hypoglycemics, nonsteroidal anti-inflammatory drugs, spironolactone or warfarin, DO NOT use herbal supplements without first checking with your doctor.

Name of Remedy
Ephedra (Ephedra sinica, also called Ma-Huang)
To treat coughs and obesity
Dangerous and life-threatening increases in heart rate and blood pressure. Has potentially fatal interactions with many heart medications.
Garlic (Allium sativum)
To lower cholesterol; to prevent and treat colds and certain infections
Excessive bleeding in people who are taking anticoagulant medications such as warfarin (Coumadin).
Ginkgo (Ginkgo biloba)
To improve mental functioning, circulation; to prevent altitude sickness
Increases the risk of excess bleeding when taken with anticoagulant drugs. Interferes with action of diuretics.
Goldenseal (Hydrastis canadensis)
To treat constipation; acts as an anti-inflammatory
Contains substances that change the way your body processes many medications, so it should be used with caution with heart medication.
Hawthorn (Crataegus species)
To treat congestive heart failure and high blood pressure
Should not be taken by anyone taking heart medications without guidance from your doctor.
Licorice root (Glycyrrhiza glabra)
To treat coughs, cirrhosis and stomach ulcers
Should not be used by anyone with a heart condition or by anyone taking heart medications. Raises blood pressure.

High levels of vitamin K are also a problem, as vitamin K interferes with warfarin. Many foods are high in vitamin K, which may affect the way warfarin works. Leafy green vegetables have the highest content of vitamin K; other foods high in vitamin K include Brussels sprouts, cabbage, broccoli, asparagus, okra and frozen peas. It is important to keep your diet consistent. Avoiding foods that contain vitamin K is not necessary if you are taking warfarin, but talk to your healthcare provider to adjust your dose, based on how much vitamin K is in your diet, or if you plan to make major changes in your diet.

Other supplements that may cause heart problems, whether or not a person is also taking heart medications:

  • Aloe: used internally to relieve constipation and externally to soothe irritated skin and burns. When taken internally, it can lower levels of potassium, so avoid aloe if you take diuretics and digoxin.
  • Arnica (Arnica montana): applied externally to reduce pain from bruising, aches, and sprains, and to relieve constipation. Arnica is potentially toxic to the heart and can raise blood pressure if taken internally.
  • Black cohosh (Cimicifuga racemosa): used in order to relieve menopausal symptoms. Can lower blood pressure when taken at high doses or with antihypertensive medications.
  • Beta carotene: antioxidant thought to fight free radicals (substances that harm the body when left unchecked). Using vitamin supplements that contain beta carotene should be actively discouraged because of an increased risk of death. Choose supplements with mixed carotenes.
  • Feverfew (Tanacetum parthenium): believed to prevent and treat migraines, arthritis and allergies. Feverfew can interfere with blood clotting when taken internally.
  • Ginger: thought to relieve nausea and motion sickness, lower blood cholesterol, decrease platelet aggregation and act as a digestive aid and antioxidant. Ginger can interfere with blood clotting.
  • Ginseng (Panax ginseng): thought to slow aging, increase mental and physical capacity, increase sexual performance and boost immunity. It should not be taken by people with hypertension (high blood pressure).
  • Nettle (Urtica dioica): thought to fight urinary tract infections, kidney and bladder stones, and rheumatism. It is used externally to control dandruff. Nettle should not be taken by people with fluid retention caused by reduced heart or kidney function.

The FDA's medical products reporting program tracks reports of serious adverse events of products. MedWatch can be contacted at 888.723.3366 (www.fda.gov/medwatch). You can also call the FDA consumer hotline at 1.888.INFO.FDA (1.888.463.6332).

Medically Reviewed

Last reviewed by a Cleveland Clinic medical professional on 11/12/2019.

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