Horseradish - Uses and Side Effects

Horseradish has been cultivated for about 2,000 years. Early settlers brought the plant to America. Early uses included reducing sciatic nerve pain, expelling afterbirth, relieving colic, increasing urination, and killing intestinal worms. Horseradish is one the "five bitter herbs" of Passover.

Topically, the mustard content irritates the skin and stimulates local blood flow, giving relief to minor muscle aches and inflamed joints or tissues. Both the mustard oil and the glucosinolate composition give the root its characteristic pungency, helping to decrease congestion and inflammation of the respiratory tract. Horseradish may also have some antimicrobial activity against both gram-negative and gram-positive bacteria. Horseradish is available as fresh or dried root, ointment with 2% mustard oil from pressed root, and tincture.

Reported uses

Horseradish is used orally to decrease sinus congestion, relieve cough from congestion, and treat edematous conditions. It's also used as an adjunctive treatment for urinary tract infections and kidney stones.

Horseradish is used in foods as a flavoring agent. It's used topically for respiratory congestion and minor muscle aches.

Administration

Oral use: Typical doses range from 6 to 20 g every day of the root or equivalent preparations

Topical use: Ointments contain a maximum of 2% mustard oil and are applied as needed.

Hazards

Adverse reactions following use of horsedish may include mucous membrane inflammation, GI irritation, abdominal pain, diarrhea, decreased thyroid function, skin irritation and biistenng, and topical allergic reaction. Bloody vomiting and diarrhea may occur wIth large doses. Use with anticoagulants or antiplatelet drugs may cause increased bleeding tendencies. When used with levothyroxine or hypothyroid therapy, it may further decrease thyroid function. Concomitant use of horseradish with NSAIDs may increase frequency of GI irritation.

Those with kidney inflammation should avoid using horseradish because of its diuretic effect. Patients with infectious or inflammatory GI conditions or stomach or intestinal ulcers and children younger than age 4 should avoid use. Pregnant patients should avoid taking large oral doses because of the toxic and irritating mustard oil components. Patients with thyroid conditions and those taking an anticoagulant or an NSAID should use horseradish with caution.

Clinical considerations

Tincture doses taken regularly and in large amounts may have abortifacient effects.

Before applying horseradish topically to a large area, the patient should test it on a small area first to see how he responds.

If patient has hypothyroid disease, warn about possible interaction with horseradish and any other plants from the cabbage family.

Advise patient to stay within the recommended dose of 20 g per day and to take the herb with meals, to minimize GI Irritation and upset.

Tell patient to discontinue herb if adverse reactions such as GI irritation and pain occur.

Advise patient to keep the herb out of reach of children and pets.

Tell patient to remind pharmacist of any herbal or dietary supplement that he's taking when obtaining a new prescription.

Advise patient to consult his health care provider before using an herbal preparation because a conventional treatment with proven efficacy may be available.

Research summary

The concepts behind the use of horseradish and the claims made regarding its effects haven't yet been validated scientifically.