IngredientsThe accepted scientific name is Cytisus scoparius (L.) Link. The plant carries a long list of synonyms reflecting its complex taxonomic history. Botanical synonyms include Spartium scoparium, Genista scoparius (Lam.), and Sarothamnus scoparius. Common names in English and other European languages are numerous. These include Bannal, Besenginaterkraut, Broom, Broom top, Ginsterkraut, Herba genistae scopariae, Herba spartii scoparii, Herbe de genet Ă balais, Hog weed, Irish broom top, Sarothamni herb, Scoparii cacumina, Scotch broom, and Scotch broom top.
The local names Basam, Bisom, Bizzom, Breeam, Browme, Brum, and Green Broom have all been given to the plant in reference to the practice of making brooms from it. The former genus name Sarothamnus also reflects this use, being formed from Greek words signifying "to sweep" and "a shrub." The specific epithet scoparius is derived from the Latin scopa, meaning a besom.
Cytisus scoparius, commonly known as Scotch broom or common broom, is a deciduous to semi-evergreen leguminous shrub in the family Fabaceae, native to western and central Europe. Plants typically grow to 1–3 metres (3½–10 feet) tall, rarely to 4 m (13 ft), with main stems up to 5 centimetres thick. Stems are ridged and green. The shrubs have green shoots with small deciduous trifoliate leaves 5–15 millimetres long, and in spring and summer are covered in profuse golden yellow flowers 20–30 mm long and 15–20 mm wide.
The densely growing broom shrub is indigenous to England and common across temperate Europe and northern Asia, being found in abundance on sandy pastures and heaths. It is sparingly naturalized in sandy soil in North America. The species was introduced as a garden ornamental to North America and is now common across western Canada and California.
Scotch broom is a plant in which the flower and the parts that grow above the ground are used as medicine. Scotch broom preparations, particularly those made from the flower, have been used traditionally as diuretics.
Traditional dosing used 1 teaspoon of the chopped flower shoots in water 3 to 4 times a day, or 1 to 1.5 g of the dried herb. Extracts and tinctures have also been prepared. Infusions, decoctions, and tonics prepared from fresh or shade-dried flowers are also documented preparations.
Both gorse and Scotch broom have been appraised from ancient times for their high content in bioactive compounds. Several species of the genus Cytisus have been used in folk medicine.
Historically, and as their name suggests, broom species were used for broom production but also for thatching, fence rows (stems), cattle fodder (green photosynthetic stems), beer production (flowers), and as a coffee substitute (seeds). The tough, flexible twigs were also employed in basketry, brush-making, and thatching roofs. Fibers extracted from the bark served in the production of paper, cloth, nets, and even dyes, showcasing its versatility as a resource in pre-industrial societies.
The generic name Cytisus is said to be a corruption of the name of the Greek island Cythnus, where broom abounded, though it is probable that the broom known to the ancients, and mentioned by Pliny and by Virgil under the name Genista, was another species—the Spanish Broom, Spartium junceum—as common broom is not found in Southern and Eastern Europe, being chiefly a native of Western, Northern, and Central Europe.
The medicinal use of the brush-like branches of the broom, under the name Genista, Genesta, or Genestia, is mentioned in the earliest printed herbals.
Historical European herbalists documented a range of uses for the aerial parts of Scotch broom. These included treatment of jaundice; swelling or hardness of the liver, spleen, or abdominal organs; nephritic conditions and edema; and gravel and stones of the kidney, bladder, and gallbladder. Other traditional uses included treatment of bleeding gums, hemophilia, gout, achy muscles and joints (rheumatism), sciatic nerve pain, gallstones, kidney stones, spleen disorders, and yellowing of the skin.
Despite serious safety concerns, Scotch broom has been used for heart problems including fluid retention (edema), poor circulation, low blood pressure, fast heartbeat, and irregular heartbeat. British herbalists of the 18th century praised its diuretic and sedative properties—sparteine was thought to ease urinary retention and support heart rhythm.
Cytisus scoparius was not originally part of classical Ayurvedic texts like the Charaka Samhita or Sushruta Samhita, but there are records of its use in folk Ayurveda in Himachal Pradesh and Uttarakhand, brought by European settlers centuries ago.
The characteristic constituents of C. scoparius are biogenic amines (mostly tyramine in the young shoots), flavonoids (spiraeoside and scoparoside), isoflavones and their glycosides (genistin), as well as allelopathic quinolizidine alkaloids (mostly sparteine, lupanine, scoparin, and hydroxy-derivatives), which defend the plant against insect infestation and herbivores.
Quinolizidine alkaloids reported present in the plant include sparteine, sarothamine, and lupanine. One of the main alkaloids of this plant is cytisine. Sparteine is pharmacologically the most extensively characterized of these alkaloids. Sparteine is a quinolizidine alkaloid that has numerous pharmacological properties both in humans and animal models. Since only sparteine can be easily isolated from broom (Cytisus scoparius), it is the only lupin alkaloid that is commercially available and exploited in medicine as an antiarrhythmic drug.
The plant Cytisus scoparius contains the flavone 6''-O-acetyl scoparin, flavonols namely rutin, quercetin, quercitrin, isorhamnetin, and kaempferol, and isoflavones including genistein and sarothamnoside. Other identified flavonoids in C. scoparius include apigenin, isoquercetin, isorhamnetin, sarothamnoside, and kaempferol. In Cytisus scoparius seed pods, orientin was the predominant flavone, while the flowers were rich in rutin, quercetin, and isoquercetin.
Benzenoid compounds including tyramine, hydroxytyramine, phenylethanol, and cresol have also been reported to be present in the plant. Early biochemical research identified tyramine and hydroxytyramine as blood-pressure-raising substances of the pod of common broom (Sarothamnus scoparius), documented by Schmalfuss and Heider in 1931.
The plant also contains amino acids, a volatile oil (containing 4-mercapto-4-methylpentane-2-one), coumarins, caffeic acid derivatives, tannin, wax, fat, and sugars. The essential oil of the fresh flowers contains alcohols, coumarins, eugenol, benzoic acid, guaiacol, and fatty acids.
Sparteine's primary antiarrhythmic action is achieved through the inhibition of sodium channels in cardiac cells and ganglionic blocking effects. Pharmacokinetically, it is influenced by genetic variability in its metabolism by the CYP2D6 enzyme. By blocking sodium channels, sparteine reduces the influx of sodium ions during the depolarization phase of the cardiac action potential, stabilizing the cardiac membrane and decreasing the excitability of the heart muscle, thereby reducing the occurrence of abnormal heart rhythms. Additionally, sparteine has a mild ganglionic blocking action affecting the autonomic ganglia, which relay signals in the autonomic nervous system. By inhibiting these ganglia, sparteine can influence heart rate and blood pressure, adding to its antiarrhythmic properties.
Among the reported effects of sparteine are reduced cardiac conductivity, stimulation of uterine motility, circulatory collapse, and respiratory arrest.
In the central nervous system, sparteine reduces locomotor activity and has light analgesic effects; it also has no effects on short-term memory or spatial learning and does not induce changes in behavior or electroencephalographic (EEG) activity.
Sparteine undergoes primary metabolism in the liver through the cytochrome P450 enzyme CYP2D6, which catalyzes its oxidation to two major metabolites: 2-dehydrosparteine and 5-dehydrosparteine. These metabolites are formed via N-oxidation, with CYP2D6 exhibiting stereoselective activity in this process. The enzyme's role is critical, as sparteine serves as a prototypic substrate for assessing CYP2D6 activity in vivo. The metabolism of sparteine is subject to significant pharmacogenetic variability due to polymorphisms in the CYP2D6 gene. Pharmacokinetic studies have shown that the metabolic oxidation of sparteine exhibits genetic polymorphism and that approximately 6–9% of the Caucasian population are poor metabolizers.
Scotch broom contains tyramine, and large amounts of tyramine can cause high blood pressure. The body naturally breaks down tyramine, which usually prevents it from causing hypertension. Tyramine acts as a sympathomimetic compound, causing the release of norepinephrine and interacting with adrenergic receptors, leading to vasoconstriction and changes in blood pressure.
Scotch broom preparations, particularly those made from the flower, have been used traditionally as diuretics. Diuretic effects have been attributed by some researchers to the constituent scoparin or scoparoside.
Most of the reported biological activities and active constituents of this plant may be related to its antioxidant nature. Flavonoids and other phenolic compounds (hydroxycinnamic derivatives, catechins, etc.) of plant origin have been studied in the context of oxidative stress defense. Flavonoids and other polyphenolic compounds have gained the greatest attention in this regard.
Sparteine has been studied as a class 1a anti-arrhythmic agent to reduce the incidences of ventricular tachycardia and fibrillation, and to reduce heart rate and blood pressure. The isolated alkaloid sparteine was formerly available as a pharmaceutical agent in this context. Sparteine, which has been used as an antiarrhythmic and as an oxytocic, shows a wide range of plasma concentrations due to CYP2D6 catalyzing the formation of 2- and 5-dehydrosparteine. Sparteine has been used as a marker of the metabolic activity of CYP2D6.
Evidence strength: Both the flower and herb of Scotch broom have been used medicinally, but 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. Clinical trials are lacking to support any pharmacological use, and there is no recent clinical evidence to guide dosing. Evidence for cardiac effects of the whole herb in humans is therefore indirect and based primarily on the known pharmacology of the isolated alkaloid sparteine rather than on controlled clinical trials of the plant preparation itself.
Pharmacological studies have confirmed the uterine stimulant effect and antispasmodic activity of C. scoparius. It has also been found to have diuretic activity, hypotensive activity, and an estrogenic effect. Scotch broom has a diuretic effect on the body, which may make it useful for edema caused by a cardiac condition. The mechanism for diuresis has traditionally been attributed to scoparin (a flavone glycoside) rather than to the alkaloids.
Evidence strength: The diuretic activity has been documented in pharmacological studies but rigorous controlled human clinical trials of Scotch broom preparations specifically for diuretic endpoints are absent from the peer-reviewed literature. Evidence remains preclinical or based on traditional use.
The antioxidant activity of extracts of the aerial parts of Cytisus scoparius has been evaluated in vitro. The plant extract was tested for DPPH radical scavenging, nitric oxide radical scavenging, superoxide anion radical scavenging, hydroxyl radical scavenging, antilipid peroxidation activity, reducing power, and total phenol content. The extract exhibited scavenging potential with IC50 values of 1.5 ÎĽg/ml, 116.0 ÎĽg/ml, and 4.7 ÎĽg/ml for DPPH, nitric oxide, and superoxide anion radicals, respectively.
Cytisus scoparius, C. multiflorus, and C. striatus were evaluated for their total phenolic content and antioxidant activity by several in vitro methods. C. scoparius demonstrated the highest content in total phenolic compounds among the three species, with values of 427.10 mg GAE/g extract.
Cytisus scoparius has been shown in in vitro experiments to be endowed with antioxidant activity. A study was carried out to evaluate it for anxiolytic, antidepressant, and antioxidant activity in stressed rats. A 60% methanolic extract of C. scoparius was quantified for phenolic content by Folin-Ciocalteu's method.
Evidence strength: Antioxidant data are predominantly from in vitro studies. No controlled human clinical trials have been conducted to evaluate the antioxidant benefits of Scotch broom preparations in vivo. This evidence is preliminary.
Polyphenolic compounds were extracted from C. scoparius by adjusted hydro-organic solvent mixtures, and these extracts' in vitro antimicrobial activity was evaluated on Gram-positive and Gram-negative pathogenic bacteria, with special attention to those involved in food contamination. The biofilm dispersion was assessed on Listeria monocytogenes, Staphylococcus aureus, and Pseudomonas aeruginosa. The extracts showed antimicrobial activity against the pathogenic species tested, presenting IC50 values between 0.625–20% v/v. Results from the biofilm dispersion assays revealed that the extracts exhibit antibiofilm activity against the pathogenic bacteria tested.
Analytical work suggested that 3,4,5-trimethoxycinnamic acid and its derivatives may be responsible for the antimicrobial activity of certain C. scoparius extracts. Apigenin and methoxybenzaldehydes, both polyphenols present in one extract fraction but absent in another, have been reported to have activity against S. aureus and E. coli.
Evidence strength: All antimicrobial data are from in vitro laboratory studies. No human clinical trials have been conducted. Evidence is preliminary and exploratory.
Sparteine was formerly used to induce labor but should be considered contraindicated during pregnancy. Rupture of the uterus has been reported. Sparteine never gained any importance in obstetrics due to severe side effects. Broom contains sparteine, a powerful oxytocic compound.
Evidence strength: The oxytocic effect of isolated sparteine has been documented clinically; however, these effects represent a serious safety hazard rather than a therapeutic application, and the use of sparteine as an oxytocic has been abandoned due to its adverse effect profile.
The anticonvulsant profile of sparteine is not fully characterized in experimental animals, and there are no data in humans. A review has focused on the experimental evidence supporting the anticonvulsant action of sparteine in models of acute seizures and status epilepticus, as well as its possible mechanisms of action.
Evidence strength: Preclinical only; no human clinical trial data available.
Research has explored the potential use of C. scoparius extracts in topical applications for skin protection against oxidative damage. González et al. published work on the potential use of Cytisus scoparius extracts in topical applications for skin protection against oxidative damage, published in the Journal of Photochemistry and Photobiology B in 2013.
Evidence strength: In vitro/laboratory study. No human clinical trial data available.
Cytisus flowers have been considered for exploitation as raw materials for the development of new food ingredients (antioxidants, preservatives, additives, etc.), nutraceuticals, or even direct therapeutic agents (anticancer, antibacterial, etc.). Some flavonoids have been identified in all three reviewed Cytisus species, not significantly different among them. Most of the described works (mainly about C. scoparius) are directed at antioxidant activity.
Taking into account the use of brooms in traditional medicine, some studies on their bioactivities and possible applications have been conducted. However, few studies corroborate their results with the traditional use of these species, and the chemical profile is not much explored.
Clinical trials are lacking to support any pharmacological use, and there is no recent clinical evidence to guide dosing.
Traditional dosages (as reported in historical and reference sources):
No modern clinical studies have established evidence-based dosages for any indication. All dosage information above reflects historical and traditional use records only, and no dosage derived from controlled clinical trials exists for this plant.
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 the herb (above-ground parts). C. scoparius contains toxic alkaloids that depress the heart and nervous system.
Among the reported effects of sparteine at toxic doses are reduced cardiac conductivity, stimulation of uterine motility, circulatory collapse, and respiratory arrest.
Scotch broom is considered likely unsafe when taken by mouth during pregnancy, as it might cause a miscarriage. It is also considered likely unsafe to take by mouth during breast-feeding. It is contraindicated in pregnancy and cardiomyopathies, including hypertension. Cytisine is not recommended to be taken by pregnant women due to the potential risk of embryotoxic action. Sparteine was formerly used to induce labor but should be considered contraindicated during pregnancy. Rupture of the uterus has been reported.
The herb is contraindicated in cardiomyopathies, including hypertension. Although sparteine was studied historically as an antiarrhythmic, the narrow therapeutic window and serious adverse effects—including effects on cardiac conductivity—make unsupervised use of the whole herb particularly hazardous in individuals with pre-existing cardiac disease.
Scotch broom contains the toxic alkaloid sparteine, which is metabolized (broken down) by the liver's cytochrome P450 2D6 (CYP2D6) isoenzyme system. Therapy should be monitored if broom is administered with drugs that are CYP2D6 inhibitors. Quinidine, haloperidol, and moclobemide are all potent inhibitors of the oxidative metabolism of sparteine. Quinidine in particular seems to decrease the breakdown of Scotch broom, and taking Scotch broom along with quinidine might increase the risk of serious side effects.
Scotch broom contains tyramine, and large amounts of tyramine can cause high blood pressure. Some medications used for depression called MAOIs stop the body from breaking down tyramine, which can cause there to be too much tyramine and lead to dangerously high blood pressure. These medications include phenelzine (Nardil), tranylcypromine (Parnate), and others.
Pharmacokinetic studies have shown that the metabolic oxidation of sparteine exhibits genetic polymorphism and that approximately 6–9% of the Caucasian population are poor metabolizers. In poor metabolizers of CYP2D6, sparteine accumulates to higher plasma levels, increasing the risk of cardiac and other toxicities relative to extensive metabolizers.
Patients with simultaneous administration of cytisine and active smoking could experience aggravated adverse effects of nicotine (nicotine intoxication). Cytisine was originally characterized as a selective, partial agonist with high affinity for α4β2* nicotinic acetylcholine receptors (nAChRs). Although cytisine-based smoking cessation products have been studied and are marketed in some Eastern European countries under brand names such as Tabex, these products are based on purified cytisine rather than whole Scotch broom preparations. Whole Scotch broom should not be equated with cytisine pharmaceutical products.
A fatal ingestion of sparteine combined with meprobamate has been documented in the forensic medical literature, reported by Mangin et al. in 1989 in Acta Medica Legalis et Socialis, underlining the capacity of sparteine to cause death in overdose scenarios.
The German Commission E, which reviewed medicinal herbs, evaluated Scotch broom herb (herba) and flower separately. The American Botanical Council's online portal lists both a Commission E monograph for the herb (as an approved herb) and a separate entry for the flower; however, the full monograph content was not accessible via open-access retrieval. No current publicly accessible European Medicines Agency (EMA/HMPC) monograph specific to Cytisus scoparius was identified in the search results. European Union (EU) herbal monographs contain the HMPC's scientific opinion on safety and efficacy data about a herbal substance and its preparations intended for medicinal use.
Although there are some interesting studies that approach other kinds of applications for extracts of different brooms, more studies could be carried out. The overall state of the evidence base for Scotch broom as a dietary supplement reflects a plant with well-understood constituent pharmacology—particularly for sparteine—but a notable deficit of modern controlled human clinical trials for any therapeutic indication.
Health conditions that Scotch broom may help support.
Body systems that Scotch broom may help support.
Go back