horseweed

Horseweed, or Conyza canadensis, is a flowering weed native to North America, but is now found all over the world. Horseweed has been traditionally used to treat diarrhea, bladder problems, menstrual irregularities, and other ailments, however, there are no scientific studies to support any of its uses.

The young leaves of horseweed are edible, and dried leaves have a spicy flavor similar to tarragon. Horseweed essential oil is used for flavoring in some candies, condiments, and soda. Dried horseweed stems can be used for a drill to make fire with friction.

The medicinal properties of horseweed may come from the chemical substances it contains, including essential oils, tannins, triterpenoids, phenolic acids, sphingolipids, acetylenes, and steroids. Horseweed is believed to have properties that help tighten tissues (astringent), promote urination (diuretic), arrest bleeding (hemostatic), and invigorate (tonic) body and mind. Horseweed leaves are a good source of nutrients including carbohydrates, protein, fat, fiber, calcium, potassium, and phosphorous.

Suggested uses of horseweed include:

• Diarrhea and dysentery
• Internal hemorrhage
• Hemorrhoids
• Menstrual irregularities
• Bladder problems
• Nosebleeds
• Fevers
• Cough
• Bronchitis

• Do not use horseweed if you are allergic to Asteraceae family plants such as ragweed, chrysanthemum, marigold, and daisies.
• Horseweed may slow the blood clotting process and increase the risk of bleeding and bruising. Avoid concurrent use with blood-thinning medications such as warfarin. Stop using horseweed at least 2 weeks before a scheduled surgery.
• Do not take horseweed if you have contact dermatitis, it can worsen the condition.

Common side effects of horseweed include:

• Contact dermatitis

Call your doctor immediately if you experience any of the following symptoms or serious side effects while using this drug:

• Serious heart symptoms include fast or pounding heartbeats, fluttering in your chest, shortness of breath, and sudden dizziness;
• Severe headache, confusion, slurred speech, severe weakness, vomiting, loss of coordination, feeling unsteady;
• Severe nervous system reaction with very stiff muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, and feeling like you might pass out; or
• Serious eye symptoms include blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights.

This is not a complete list of all side effects or adverse reactions that may occur from the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may also report side effects or health problems to the FDA at 1-800-FDA-1088.

There is no reliable scientific information on what might be an appropriate dosage of horseweed. Refer manufacturer’s label.

Suggested dosing:

• Dried flowering plant

Infusion

• Steep 1 tsp dried horseweed in 1 cup water for 30 minutes.
• Drink 1-2 cups a day.

Enema

• Steep 1 tsp dried horseweed in 1 quart of boiling water for 20 minutes.
• Use while warm.

Overdose

Horseweed overdose is not known to cause serious symptoms. Generally, there are no effects from skin contact but overdose from ingestion may irritate the mucous membranes, with symptoms such as a runny or stuffy nose and sore throat. Symptoms should resolve with the discontinuation of horseweed.

Inform your doctor of all medications you are currently taking, who can advise you on any possible drug interactions. Never begin taking, suddenly discontinue, or change the dosage of any medication without your doctor’s recommendation.

• Horseweed has no known severe or serious interactions with other drugs.
• Horseweed may have moderate interactions with drugs that slow the blood clotting process.
• Horseweed has no known mild interactions with other drugs.

The drug interactions listed above are not all of the possible interactions or adverse effects. For more information on drug interactions, visit the RxList Drug Interaction Checker.

It is important to always tell your doctor, pharmacist, or health care provider about all prescription and over-the-counter medications you use, as well as the dosage for each, and keep a list of the information. Check with your doctor or healthcare provider if you have any questions about the medication.

• There is no reliable information on the safety of horseweed use by pregnant or breastfeeding women. Avoid use.
• Do not use any herbal product including horseweed without first checking with your healthcare provider, if you are pregnant or breastfeeding.

• Horseweed is possibly safe for most adults if used in recommended doses.
• Use horseweed exactly as per label instructions.
• Check with your healthcare provider before taking any herbal product, including horseweed.
• Herbal products often contain many ingredients. Check labels for the components in the horseweed product you choose.
• Horseweed is marketed as an herbal supplement and is not regulated by the FDA. Products may differ in formulations and strengths, and labels may not always match contents; exercise caution in choosing your product.
• Store horseweed safely out of reach of children.
• In case of overdose, seek medical help or contact Poison Control.