Scotch broom

Scotch broom ( Cytisus scoparius ), also referred to as broom, is a perennial woody plant native to Europe. The species was introduced as a garden ornamental to North America and now is common across western Canada and California. Scotch broom plants grow up to 10 feet tall, with sharply angled branches off the main stem, trifoliate leaves, and bright yellow small flowers. Scotch broom spreads quickly and aggressively at the expense of other plants and trees, and is often considered a pest.

Both the flower and herb of scotch broom have been used medicinally. There is very little available scientific evidence about the efficacy or safety of this plant, and most conclusions come from knowledge of its constituents, or from traditional use. There is particular concern about the potential toxicity of scotch broom due to the presence of small amounts of the toxic alkaloids sparteine and isosparteine, which are found in both the flowers and herb (above-ground parts). Sparteine has known effects on the electrical conductivity of heart muscle and can potentially cause dangerous heart rhythms or interact with cardiac drugs. Sparteine is also known to cause uterine contractions, and should be avoided during pregnancy. Life-threatening adverse effects have been associated with sparteine, and therefore scotch broom should be used only under strict medical supervision.

Synonyms

Bannal, basam, Besenginaterkraut, besom, bissom, bream, broom, broom tops, broomtops, browme, brum, common broom, Cystisus scoparius , Cystisi scoparii flos, Cytsus scoprfus , English broom, European broom, genet a balais, Genista andreana , Genista scoparius (Lam.), Ginsterkraut, greem broom, herba spartii scoparii, herbe de genet a balais, herbe de genistae scopariae , herbe de hogweed, hogweed, Irish broom, Irish tops, sarothamni herb, Sarothamnus scoparius (Koch), Sarothamnus vulgaris , scoparii cacumina, scopari herba, scotch broom top, scotchbroom, sparteine, Spartium scoparium Linn., sumidad de retma de escobas.

Family: Fabaceae/Leguminosae/Papilionaceae.

Note: Not to be confused with Spanish Broom ( Spartium junceum ) which has been associated with severe toxicity, or Butcher's broom ( Ruscus aculeatus ).

Evidence

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

Uses based on scientific evidence	Grade^*
Cardiovascular conditions Scotch broom herbhas been taken by mouth traditionally for a variety of conditions related to the heart or blood circulation. These include abnormal heart rhythms (arrhythmias), fast heart rate (tachycardia), swelling in the legs (peripheral edema), water in the lungs (pulmonary edema; congestive heart failure), and low blood pressure (hypotension).Scotch broom flowerhas been taken by mouth traditionally for tachycardia and to reduce leg swelling by increasing urination (diuretic), as well as for damage to the heart muscle (cardiomyopathy) and for poor circulation.There is a scientific basis for some of these uses, due to the presence in scotch broom herb and flower of small amounts of the alkaloid sparteine. Sparteine may affect the electrical conductivity of heart muscle (similar to type 1A antiarrhythmic drugs such as quinidine). However, there is limited evidence in humans, and it is not clear if sparteine found in the plant form has clinically meaningful effects. These potential properties of scotch broom may be dangerous in individuals with heart disease or taking cardiac medications. People with cardiovascular disorders should be evaluated and supervised by a licensed healthcare professional.	C
Diuretic (increased urine flow) Scotch broom preparations, particularly those made from the flower, have been used traditionally as diuretics (to increase urination). Diuretic effects have been attributed by some to the constituent scoparin or scoparoside. There is insufficient scientific evidence at this time to form clear conclusions about safety or efficacy in humans.	C
Labor induction (oxytocic) Scotch broom herb has been used historically to stimulate uterine contractions at birth, and to reduce post-partum hemorrhage (bleeding after birth). There is a scientific basis of this use, due to the presence in scotch broom of small amounts of the alkaloid sparteine, which was studied and used through the 1970s as an oxytocic drug (to induce labor). This use was discontinued due to serious toxicities associated with sparteine. Currently, other drugs such as oxytocin (Pitosin) are used for this purpose. The safety and efficacy of scotch broom preparations in labor are not well studied or established. Women who may require labor induction should be evaluated and supervised by a physician.	C

*Key to grades
A: Strong scientific evidence for this use;
B: Good scientific evidence for this use;
C: Unclear scientific evidence for this use;
D: Fair scientific evidence against this use;
F: Strong scientific evidence against this use.

Grading rationale

The below uses are based on tradition or scientific theories. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

Abscess, abnormal heart rhythm (arrhythmia), angina, astringent, beer flavor, bladder disorders, bleeding gums, blood cleansing, bronchitis, cancer, cathartic, cardiomyopathy, circulatory disorders, coagulation (bleeding) disorders, congestive heart failure, diphtheria, emetic (vomiting inducer), euphoria (when smoked in cigarettes), food flavoring, functional heart disorders, gallstones, gout, hemophilia, hypotension, hypertension, hypertrophic cardiomyopathy, inflammation, irregular heart rhythm (atrial fibrillation), intoxication, jaundice, kidney inflammation, kidney stones, lice, liver disorders, menorrhagia (excessive menstruation), muscle ache, nausea, peripheral edema, peripheral vasoconstrictor, post-partum hemorrhage, pulmonary edema, relaxation (when smoked in cigarettes), rheumatic disorders, sciatica, splenomegaly (enlarged spleen), snake bite, toothache.

Dosing

The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.

Adults (18 years and older)

Note: It is not clear what dose(s) of scotch broom are safe or effective for any medical condition, and use should only be under medical supervision. Storage of the flower or herb should be in a cool, dry location.

Flower: A juice has been made by pressing the bruised, fresh tops and adding one-third volume alcohol, allowing to sit for seven days, followed by filtration and taken daily as needed. An infusion has been made by adding 1 ounce of dried tops to a pint of boiling water (or 1 teaspoon in 200mL boiling water), and taken as a cup-full once or twice daily as needed.

Herb (above-ground parts): As a tea , 1-2 grams (1 level teaspoon) of herb can be steeped in 150-200mL of boiling water, then strained after 5-10 minutes and taken as a cup-full, up to three times daily as needed. As a decoction , 1-2 grams of herb have been used in preparations. As a liquid extract , a 1:1 preparation in 25% ethanol (v/v) has been prepared and taken as 1-2 milliliters as needed. As a tincture , a 1:5 preparation in 45% ethanol (v/v) has been taken at a dose of 0.5-2mL daily. The herb may also be available as an aqueous-ethanol preparation (1:1:5) or as an aqueous essential oil extract.

Children (younger than 18 years)

Avoid due to potentially life-threatening toxicity.

Safety

The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Avoid if hypersensitive to scotch broom or any of its constituents, including sparteine.

Oral ingestion or smoking of either the flower or above-ground parts of scotch broom may not be safe, particularly in large amounts due to the presence of the toxic alkaloids sparteine and isosparteine. Poisoning of livestock grazing on scotch broom has been reported, and nausea/vomiting has developed in children from sucking on the flowers of the related species, French broom. It has been suggested that serious toxicity may occur in adults with ingestion of high doses of sparteine, which may be present in moderate amounts in the above-ground parts of the plant. Although small amounts of scotch broom may be safe in otherwise healthy individuals, and use in foods as a flavoring or coloring agent is generally considered safe, the German Commission E recommends medical supervision when using this herb.

Signs of toxicity may include nausea, vomiting, diarrhea, dizziness, confusion, headache, and gastrointestinal distress. Sparteine ingestion has been associated with respiratory arrest, circulatory collapse, and death, although scotch broom itself has not. Other symptoms of toxicity may include weakness, palpitations, fatigue, sleepiness, dilation of the pupils, and eye muscle weakness (ocular palsy). Medical attention should be sought immediately, with management including gastric lavage and activated charcoal, as well as cardiorespiratory support as appropriate.

Scotch broom seeds have been used as a coffee substitute, which may carry a significant risk of toxicity. Toxicity can also occur when scotch broom is smoked in cigarette form, due to sparteine present in the inhaled smoke.

Scotch broom contains sparteine, and alkaloid with anti-arrhythmic properties and potential cardiac toxicity (reported as similar to class 1A antiarrhythmics such as quinidine). Blood pressure changes and circulatory collapse may occur with large doses taken in any form, including by mouth or smoked in cigarettes. There is a possibility of abnormal heart rhythms, heart attack, and worsening of heart failure. Therefore, use of this herb should only be under medical supervision, and extreme caution is warranted in individuals with a history of heart disease, abnormal heart rhythms, high blood pressure, or those taking heart medications.

High doses of scotch broom taken by mouth may cause toxicity symptoms including dizziness, headache, weakness, fatigue, sleepiness, blurry vision, sweating, and confusion. When smoked in cigarette form, headache, confusion, relaxation, and euphoria may occur, and driving or operating heavy machinery should be avoided.

Topical (skin) use may cause irritation due to the presence of saponins.

High doses of scotch broom may cause toxicity symptoms including nausea, vomiting, gastrointestinal distress, and diarrhea.

Smoking cigarettes containing scotch broom carries a risk of inhalation of fungal contaminants (aspergillus), with a possibility of resulting fungal pneumonia.

Pregnancy and Breastfeeding

Scotch broom should be avoided during pregnancy. Scotch broom contains the alkaloid sparteine, which is known to cause uterine contractions, and carries a risk of inducing abortion (abortifacient properties).

Scotch broom should be avoided during breastfeeding due to insufficient evidence and a hypothetical risk of serious toxicity.

Interactions

Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy.

Interactions with Drugs

Scotch broom contains the alkaloid sparteine, which may affect cardiac conductivity. Use in individuals taking other heart medications that affect heart rhythm such as digoxin, beta-blockers, calcium channel blockers or other antiarrhythmics may be hazardous and should be avoided unless under strict medical supervision.

Scotch broom contains the alkaloid sparteine which can potentially increase (or decrease) blood pressure. Use is not recommended in patients with a history of abnormal blood pressure or taking blood pressure medications.

Scotch broom contains the toxic alkaloid sparteine, which is metabolized (broken down) by the liver's cytochrome P450 2D6 (CYP2D6) isoenzyme system. Therefore, drugs which inhibit CYP2D6 can increase the potential toxicity of scotch broom, including a risk of life-threatening adverse events such as cardiovascular collapse. This includes the drugs amiodarone, celecoxib, chlorpheniramine, cimetidine, clomipramine, cocaine, doxorubicin, halofantrine, haloperidol, methadone, mibefradil, meclobemide, nefazodone, quinidine, ranitidine, ritonavir, terbinafine, venlafaxine, and multiple antidepressants in the selective serotonin reuptake inhibitor (SSRI) class, particularly fluoxetine and paroxetine. In particular, the drug haloperidol (Haldol) has been shown to increase blood levels of sparteine.

Scotch broom contains small amounts of tyramine, which can lead to hypertensive crisis in individuals taking MAOI drugs. Therefore, this combination should be avoided. MAOI drugs include Isocarboxazid (Marplan), phenelzine (Nardil), and tranylcypromine (Parnate).

Interactions with Herbs/Supplements

Scotch broom contains the alkaloid sparteine, which can potentially decrease or increase blood pressure. Use is not recommended in patients with a history of abnormal blood pressure or taking agents with significant effects on blood pressure.

Herbs with potential effects on heart rhythm similar to digoxin may pose a risk of heart block or abnormal cardiac rhythms when used with scotch broom, which contains the cardioactive constituent sparteine.

Scotch broom contains the toxic alkaloid sparteine, which is metabolized (broken down) by the liver's cytochrome P450 2D6 (CYP2D6) isoenzyme system. Therefore, herbs that inhibit CYP2D6 can increase the potential toxicity of scotch broom, including a risk of life-threatening adverse events such as cardiovascular collapse.

Scotch broom (Cytisus scoparius Linn.) herb and flower, Sparteine

Background

Synonyms

Evidence

Dosing

Safety

Interactions