Goldenseal - Drug Interactions, Side Effects and Precautions of Use-Herbal Medicines

Taxonomic Class

Ranunculaceae

Common Trade Names

Alvita, Dandelion Goldenseal, Golden Seal Extract, Golden Seal Extract 4:1, Golden Seal Glycerin Extract, Golden Seal Power, Golden Seal Root, Nu Veg Golden Seal Herb, Nu Veg Golden Seal Root

Common Forms

Capsules, tablets : 250 mg, 350 mg, 400 mg, 404 mg, 470 mg, 500 mg, 535 mg, 540 mg

Also available as dried ground root powder, ethanol and water extracts, teas, and tinctures.

Source

The rhizome (root stock) of Hydrastis canadensis is commonly used to manufacture the dosage forms. The main chemical components are the alkaloids hydrastine and berberine. Also present are hydrastinine, canadine, berberastine, candaline, canadaline, chlorogenic acid, carbohydrates, fatty acids, volatile oil, resin, and meconin.

Actions

Goldenseal is claimed to have antihemorrhagic, anti-inflammatory, astringent, laxative, and oxytocic properties. The pharmacologic properties are attributed to berberine and hydrastine, and scientific studies have usually focused on these alkaloids rather than on the herb itself.

An alkaloid component of goldenseal was reported to inhibit muscle contractions in rodent smooth muscle, whereas others have shown an oxytocic effect. Goldenseal extracts reduce hyperphagia and polydipsia associated with streptozocin-induced diabetes in mice.

Berberine was found to decrease the anticoagulant effect of heparin in laboratory tests of heparinated animal and human blood and to act as a cardiac stimulant (at lower doses), increase coronary perfusion, and inhibit cardiac activity (at higher doses) in animals. Antipyretic activity (greater than aspirin) and anthelmintic, antihistaminic, antimicrobial, anti muscarinic, antitumorigenic, and hypotensive effects have also been documented for berberine in animal and laboratory models.

Hydrastinine causes vasoconstriction and can produce significant changes in blood pressure.

Reported Uses

Claims for goldenseal include use for anorexia, cancer, conjunctivitis, dysmenorrhea, eczema, gastritis, GI disorders, mouth ulcers, otorrhea, peptic ulcer disease, postpartum hemorrhage, pruritus, tinnitus, and tuberculosis and as an anti-inflammatory, a diuretic, a laxative, and a wound antiseptic. There are few, if any, clinical trial data available to support these claims.

Goldenseal was found to be less effective than ergot alkaloids when used for postpartum hemorrhage in humans. Berberine has been shown to shorten the duration of acute Vibrio cholera diarrhea and diarrhea caused by some species of Giardia, Salmonella, and Shigella and some Enterobactereciae. Clinical studies in patients with hepatic cirrhosis have shown that berberine may correct some laboratory abnormalities and improve biliary secretion and function.

Dosage

Dried rhizome: 0.5 to 1 g P.O. t.i.d.

Ethanol and water extract: 250 mg P.O. t.i.d.

Adverse Reactions

CNS: CNS depression, paralysis (with high doses), paresthesias, seizures.

CV: asystole, bradycardia, heart block.

EENT: mouth ulcers.

GI: abdominal cramps and pain, diarrhea, nausea, vomiting.

Respiratory: respiratory depression (with high doses).

Skin: contact dermatitis.

Interactions

Anticoagulants: Beneficial effects of therapeutic anticoagulants may be offset. Avoid administration with goldenseal.

Antihypertensives: Goldenseal or its extracts may interfere with or increase hypotensive effects. Do not use together.

Beta blockers, calcium channel blockers, digoxin: May increase or interfere with cardiac effects of these drugs. Do not use together.

CNS depressants (alcoho benzodiazepines): May increase sedative effects. Avoid administration with goldenseal.

Contraindications And Precautions

Goldenseal is contraindicated in patients with CV disease, particularly arrhythmias, heart failure, or hypertension, and in pregnant patients.

Special Considerations

Alert Death can result from the ingestion of large alkaloid doses. Symptoms of overdose include depression, exaggerated reflexes, GI upset, nervousness, and seizures that progress to respiratory paralysis and CV collapse.

Monitor for unusual symptoms.

Monitor for signs of vitamin B deficiency (angular stomatitis, cheilosis, glossitis, infertility, megaloblastic anemia, peripheral neuropathy, seborrheic dermatitis, and seizures).

Caution the patient to avoid hazardous activities until CNS effects of goldenseal are known.

Instruct the patient not to consume goldenseal because of its potential to cause toxicity.

Points of Interest

Chronic use of goldenseal has been reported to decrease the absorption of vitamin B and thereby promote its deficiency.

Tolerance to the herb's pharmacologic effects is thought to develop after only a few weeks of chronic use.

Berberine is also a component of barberry (Berberis vulgaris).

Goldenseal extracts have been a component in sterile eyewashes for many years without supporting evidence for their inclusion. Also, the extracts or their components have been listed in the national pharmacopoeias of several countries.

Goldenseal has been inappropriately used to mask the appearance of illicit drugs on urine drug screens in humans and race horses. This information is false and originates from a fictional literary work that depicts the plant to be useful for hiding opioid ingestion.

Goldenseal has been used as a dye. The rhizome is bright yellow and popular for staining many fabrics and materials.

According to a survey inside a New York City emergency department, goldenseal tea is among the three most commonly cited herbal preparations consumed by patients .

Commentary

The pharmacologic effects of goldenseal have not been adequately studied. Because the risk of toxicity appears excessive for this plant, even some advocacy texts do not support its use for any disorder. Goldenseal and its alkaloids possess some promising pharmacologic properties; additional comprehensive, controlled studies in animals are needed before progressing to human studies.