Star of Bethlehem (Ornithogalum umbellatum L.): A Comprehensive Reference
1. Identity and Botanical Classification
Scientific Nomenclature and Taxonomy
Ornithogalum umbellatum, the garden star-of-Bethlehem, grass lily, nap-at-noon, or eleven-o'clock lady, is a perennial bulbous flowering plant in the asparagus family (Asparagaceae). The species known today as Ornithogalum umbellatum was first formally described by Linnaeus (1753), who is the botanical authority for the species (L.). O. umbellatum is the type species of the genus Ornithogalum, which contains about 50 species.
The genus name Ornithogalum means "bird's milk," a common euphemism for avian excrement, while the species epithet "umbellatum" refers to the umbel-like flower formation.
Common Names
The plant's many common names include garden star-of-Bethlehem, sleepydick, nap-at-noon, grass lily, summer snowflake, snowdrop, starflower, bird's milk, chinkerichee, ten-o'clock lady, eleven-o'clock lady, Bath asparagus, and star of Hungary. In French it is called Étoile de Bethléem or Dame d'Onze Heures, and in Spanish Estrella de Belén.
Botanical Description and Native Range
Ornithogalum umbellatum, commonly known as star of Bethlehem, is a bulbous perennial that is native to the Mediterranean region. It is native throughout southern and central Europe, and north-western Africa. O. umbellatum is a relatively short plant, occurring in tufts of basal linear leaves, producing conspicuous white flowers in a stellate pattern in mid to late spring. The flowers open late in the day, but when closed have a green stripe on the outside.
In late spring to early summer, each stem bears 10–20 starry white flowers (each to 3/4" wide) in an open, umbel-like terminal cluster. Flowers are striped green on the outside. Flowers open near noon and close at sunset or in cloudy weather.
O. umbellatum is often grown as a garden ornamental, but in North America and other areas it has escaped cultivation and can be found in many areas, where it may be considered an invasive weed. This species is listed as a Class C Noxious Weed in the State of Alabama.
Parts Used and Common Preparations
Star of Bethlehem is a plant of which the bulb contains chemicals that have been used as a medicine. The plant appears in commerce in two fundamentally different forms, which serve entirely different traditions:
- Crude botanical preparations: Active extracts have been prepared with alcohol, acetone, and with water. Historical medical interest focused on standardized extracts of the bulb.
- Bach flower essence (homeopathic dilution): Bach flower remedies are solutions of brandy and water — the water containing extreme dilutions of flower material. Bach stated that the dew found on flower petals retains the supposed healing properties of that plant. The Bach flower remedy solutions contain a 50:50 mix of water and brandy, called mother tincture. The solutions do not have a characteristic scent or taste of the plant because of dilution.
- Homeopathic dilutions: Commercial Bach preparations list Star of Bethlehem (Ornithogalum umbellatum) at 5X HPUS as the active ingredient. Products list Star of Bethlehem (Ornithogalum umbellatum) 5X HPUS as the active ingredient, with inactive ingredients of a 27% grape alcohol solution. "HPUS" indicates ingredients are in the official Homeopathic Pharmacopoeia of the United States.
Parts of the plant are considered poisonous but are used in some regional cuisines. Essences are also sold as patent remedies. Gerard describes it as a type of wild onion and quotes Dioscorides, who mentioned that the bulbs are edible. Both the bulbs and the green parts are sold at markets in Turkey.
2. Historical and Traditional Use
Ancient and Early Modern European Herbalism
In Henry Lyte's 1586 New Herbal (a translation into English of Dodoens' 1554 Cruydeboeck), reference is made to an Ornithogalum as the "White Field Onion." John Gerard, in his Herball of 1597, describes Ornithogalum as the "star of Bethlem." These early herbals recorded the plant primarily as a curiosity and food source rather than as a significant medicinal agent.
There is limited evidence of traditional internal medicinal use due to its cardiac glycoside content; some European folk remedies may have involved the plant in topical poultices or ritual practices, particularly for spiritual cleansing or protective charms. However, these uses were likely symbolic or anecdotal, given the plant's known toxicity.
Homeopathic Materia Medica (19th–20th Century)
Within classical homeopathy, Ornithogalum umbellatum was introduced into the homeopathic materia medica largely through the work of William Boericke, whose descriptions became foundational reference texts. According to Boericke's Materia Medica, it is "to be considered in chronic gastric and other abdominal indurations, possibly cancer of intestinal tract, especially of stomach and Caecum," with the center of action described as the pylorus, causing painful contraction with duodenal distention, depression of spirits, and complete prostration.
Symptomatic indications in this tradition include an agonizing feeling in chest and stomach starting from the pylorus, with flatus rolling in balls from side to side, loss of appetite, phlegmy retchings and loss of flesh, gastric ulceration even with hemorrhage, pains increased when food passes the pyloric outlet, vomiting of coffee-ground matter, distention of stomach, and frequent belching of offensive flatus.
In homeopathy, the Star of Bethlehem is known by its Latin name Ornithogalum umbellatum. It is used to treat persistent gastrointestinal problems, such as upper abdominal pain in the epigastric region, pressure, malignant tumors of the digestive tract accompanied by depression, and feeling drained and exhausted. It is also indicated for patients suffering from a state of nervous exhaustion with high sensitivity to all types of stimuli.
Bach Flower Therapy (1930s to Present)
The most prominent historical and contemporary use is in Bach flower remedies, developed in the 1930s by Dr. Edward Bach, a British physician and homeopath. Dr. Bach selected Star of Bethlehem as one of his 38 flower remedies to "comfort and soothe" shock, grief, and emotional trauma.
For Dr. Bach, Star of Bethlehem was one of the most treasured flower remedies. He used it as a go-to trauma remedy to buffer the effects of shock, such as unexpected bad news, the sudden loss of a loved one, an accident, or other traumatic event. It can also help when facing the pain of past traumas (PTSD).
The Bach Centre describes the remedy's intended indications in Bach's own words: "For those in great distress under conditions which for a time produce great unhappiness. The shock of serious news, the loss of someone dear, the fright following an accident, and such like." It is described as the remedy for the after-effects of shock, such as is caused by unexpected bad news or any unexpected and unwelcome event. It can be used just as well for the effects of a shock received many years ago, even very early in childhood.
Star of Bethlehem is one of the five constituent remedies of Bach's famous Rescue Remedy combination. The remedy comprises cherry plum (for fear of not being able to cope mentally), clematis (for unconsciousness or the 'detached' sensations that often accompany trauma), impatiens (for impatience, agitation), rock rose (for terror), and Star of Bethlehem (for the after-effects of shock).
Early 20th-Century Clinical Interest in Cardiac Use
In the mid-20th century, there was also clinical and pharmacological interest in the plant's cardiac properties as a potential substitute for digitalis. A 1954 paper by Waud (published in the Journal of Pharmacological and Experimental Therapeutics) and preliminary clinical trials published by Vogelsang in the Canadian Medical Association Journal in 1955 and in the Journal of the American Geriatrics Society in 1961 examined whether the plant could be used for congestive heart failure. Individuals reported that taking extracts of Star of Bethlehem could improve heart function, decrease lung congestion, and decrease water retention in the legs. But a formal scientific study to determine whether these benefits are typical has never been published.
3. Key Constituents and Active Compounds
Cardenolide Cardiac Glycosides
The most pharmacologically significant constituents of O. umbellatum are its cardiac glycosides of the cardenolide type. Investigations of the bulbs and leaves of Ornithogalum umbellatum L. afforded 16 cardenolides: besides the known cardiac glycosides convallatoxin, convalloside, strophalloside, convallatoxol, rhodexin A, rhodexoside, peripalloside, lokundjoside, and tholloside, seven new cardenolides were identified mainly by spectroscopic (FAB-MS, NMR) and chemical methods.
The main cardenolides were identified as glycosides of strophanthidin and sarmentogenin. For the first time, β-D-ribose and 3-acetyl-digitoxose were found as sugar moieties in the genus Ornithogalum.
Among the individually characterized glycosides, rhodexin A and rhodexoside have received particular attention. Two Kedde-positive compounds, isolated in crystalline form from bulbs of Ornithogalum umbellatum, were shown by infrared and ultraviolet spectra to be cardenolides. Paper chromatographic analyses of the hydrolysates indicated that both compounds contain sarmentogenin as the aglycone moiety, and that one is a rhamnoside while the other is the corresponding rhamnoside-glucoside. The monoglycoside was identified as rhodexin A (sarmentogenin-α-L-rhamnoside), a glycoside previously isolated from Rohdea japonica. The diglycoside, an apparently new compound, is designated rhodexoside.
Comparative phytochemical studies revealed that strophanthidin glycosides are distinctive compounds of the O. umbellatum group. Derivatives of sarmentogenin such as rhodexin A and rhodexoside, as well as peripalloside and lokundjoside, were detected frequently, but are not considered significant marker compounds of the O. umbellatum group. Chemical analyses of samples from Upper Austria, South Tyrol, France, and the Ukraine showed that the cardenolide pattern depends on regional origin, but is independent of chromosome numbers.
Additional Phytochemicals
The phytochemical literature reveals that European taxa of Ornithogalum primarily contain cardenolides, whereas African taxa are rich in cholestane and spirostane glycosides, reflecting their geographic origins. O. umbellatum also contains colchicine or structurally similar compounds, and children have been poisoned by eating the onion-like bulbs.
Mechanism of Action of Cardenolides
It has been shown that Ornithogalum umbellatum (Star of Bethlehem), a bulbous plant belonging to the lily family, contains a substance having an action very similar, if not identical with, that of the glycosides of digitalis. The most active bulbs, when assayed by the cat method, showed a potency 1.84 times that of digitalis leaves.
Cardiac glycoside-containing plants have natural toxins specifically called cardenolides or bufadienolides. These poisons are called cardiac glycoside toxins, and they interfere directly with electrolyte balance within the heart muscle. At the cellular level, cardiac glycosides affect other organ systems beyond the heart, such as the gastrointestinal, neurological, and visual systems. They inhibit the Na⁺,K⁺-ATPase ion pump found in the cell membrane of all mammalian cells, including retinal cells and the non-pigmented epithelial cells of the ciliary body.
The cardiac glycosides in Star of Bethlehem affect the heart. These chemicals can slow the heart rate down. This effect is mechanistically analogous to the clinical use of digoxin in conventional medicine, where inhibition of the Na⁺/K⁺-ATPase pump increases intracellular calcium, thereby increasing myocardial contractility and slowing conduction through the atrioventricular node.
In Vitro Cytotoxic Activity
Convallatoxin from O. umbellatum exhibits an impressive IC₅₀ of 0.002 µg/ml against human epidermoid carcinoma cells, highlighting its potential as an anticancer agent in preclinical models. This cytotoxicity is in the experimental (in vitro) realm and has not been the subject of clinical investigation. The mechanism is thought to relate to Na⁺/K⁺-ATPase inhibition, which is an essential transmembrane enzyme found in all mammalian cells; inhibition of this enzyme by several cardiotonic steroids has been associated with the cytotoxic effect on cancer cell lines of phytochemicals such as ouabain and digitoxin.
4. Scientific Evidence by Area of Use
4.1 Cardiovascular System: Congestive Heart Failure
Proposed basis: Despite serious safety concerns, people take Star of Bethlehem for congestive heart failure (CHF). Chemicals contained in the bulb have an action similar to a prescription drug called digoxin.
Human/clinical evidence: The available human clinical evidence is extremely limited in quantity, quality, and age. The primary reference points are two publications by a single researcher, A. Vogelsang, from 1955 and 1961, reporting preliminary clinical observations in patients with congestive heart failure, and a 1954 pharmacological study by Waud characterizing the cardiac action in animal models. Individuals reported that taking extracts of Star of Bethlehem can improve heart function, decrease lung congestion, and decrease water retention in the legs. But a formal scientific study is needed to determine whether these benefits are typical.
Evidence strength: The evidence for benefit in congestive heart failure is absent by modern standards. There are no published randomized controlled trials, no systematic reviews, and no regulatory approval for this use. People use Star of Bethlehem for congestive heart failure (CHF), but there is no good scientific evidence to support this use. The pharmacological rationale exists (cardenolide content with digitalis-like activity), but the narrow therapeutic margin and documented toxicity render investigational human studies ethically challenging.
4.2 Emotional Trauma, Grief, and Shock: Bach Flower Remedy Use
Proposed basis: Within the Bach flower remedy system, Star of Bethlehem is categorized as the remedy for the after-effects of emotional shock and grief. This use is deeply rooted in the tradition of flower essence therapy, which is based on the belief that certain flowers have energetic properties that can help balance negative emotional states.
Human/clinical evidence: Star of Bethlehem has been clinically studied primarily as a component of Rescue Remedy, not in isolation. A number of investigations have been conducted on the potential effectiveness of Rescue® Remedy. One double-blind clinical trial compared 53 individuals who ingested several measured standard doses of Rescue® Remedy with 58 control subjects who received placebo preparations. Although the placebo effect appeared to operate in both groups, Rescue® Remedy significantly outperformed the placebo in reducing stress in the subsample characterized from test scores as experiencing a "high" level of anxiety.
A second double-blind trial, conducted at the University of Miami, specifically examined the product for the reduction of acute situational stress in 111 individuals aged 18 to 49. A standard dosage of Rescue Remedy was compared against a placebo of identical appearance, and the Spielberger State-Trait Anxiety Inventory (STAI) was administered before and after. The results suggest that Rescue Remedy may be effective in reducing high levels of situational anxiety.
A small crossover pilot study by Yang and Wang (2012) examined autonomic effects: In this two-stage crossover trial, seven females (mean age 26±4 years) were randomly assigned to a sequence of two treatments (Rescue Remedy and placebo) with a one-month wash-out period. The Rescue Remedy consisted of four drops of five flower essences (cherry plum, clematis, impatiens, rock rose, and Star of Bethlehem) dissolved in brandy and 250 ml of distilled water. The placebo consisted of four drops of brandy in 250 ml of distilled water. This study is too small to draw firm conclusions.
For examination anxiety specifically, three placebo-controlled RCTs examined the efficacy of Bach flower remedies for the treatment of examination anxiety in 272 students between the ages of 18 and 65. These three RCTs of BFRs for students with examination anxiety, and one RCT of BFRs for children with ADHD, showed no overall benefit in comparison to placebo.
An additional RCT examined Rescue Remedy in psychiatric patients: a study reported on the efficacy of Rescue Remedy for treating anxiety in 98 psychiatric patients (with diagnoses of anxiety disorder, depression, or depressive symptoms during a non-acute schizoaffective psychosis) who had anxiety as their main symptom. After three days of therapy, there was no difference in improvement on the anxiety measure of a visual analogue scale between the BFRs and placebo group.
Systematic review conclusions: Seven randomized clinical trials were located in a systematic review by Ernst (Swiss Med Wkly, 2010). All but one were placebo-controlled. All placebo-controlled trials failed to demonstrate efficacy. It is concluded that the most reliable clinical trials do not show any differences between flower remedies and placebos.
The 2009 Thaler et al. systematic review in BMC Complementary and Alternative Medicine, which searched MEDLINE, Embase, AMED, and the Cochrane Library, reached similar conclusions: four randomised controlled trials and two additional retrospective, observational studies were identified. Three RCTs for examination anxiety and one RCT for ADHD showed no overall benefit in comparison to placebo. Due to the number and quality of the studies the strength of the evidence is low.
Evidence strength: The hypothesis that flower remedies are associated with effects beyond a placebo response is not supported by data from rigorous clinical trials. All randomized double-blind studies, whether finding for or against the solutions, have suffered from small cohort sizes, but the studies using the best methods found no effect over placebo. Perhaps the probable means of action for flower remedies is as placebos, enhanced by introspection on the patient's emotional state or being listened to by the practitioner. Evidence for Star of Bethlehem specifically as an isolated agent for emotional trauma is entirely absent from the peer-reviewed literature.
4.3 Gastrointestinal Conditions (Homeopathic Use)
Proposed basis: In classical homeopathy, O. umbellatum is indicated for chronic gastric conditions. It is used in homeopathy to treat persistent gastrointestinal problems, such as upper abdominal pain in the epigastric region, pressure, malignant tumors of the digestive tract accompanied by depression, and feeling drained and exhausted.
Human/clinical evidence: There are no published randomized controlled trials or observational human studies examining O. umbellatum preparations for any gastrointestinal indication. The indications listed in homeopathic materia medica texts (Boericke) reflect clinical impressions from the 19th and early 20th centuries and have not been tested in controlled settings.
Evidence strength: Absent. Regulatory agencies note that claims based on traditional homeopathic practice are not accepted medical evidence and have not been FDA evaluated. Homeopathic products have not been evaluated by the Food and Drug Administration for safety or efficacy, and the FDA is not aware of scientific evidence to support homeopathy as effective.
4.4 In Vitro Anticancer Activity (Preclinical Only)
Evidence summary: Convallatoxin, one of the major cardiac glycosides identified in O. umbellatum, has shown in vitro cytotoxic activity. Convallatoxin from O. umbellatum exhibits an IC₅₀ of 0.002 µg/ml against human epidermoid carcinoma cells. This finding is in vitro only. Cardiac steroids/cardiac glycosides display strong anti-cancer activity to induce activation of cell death or impairment of cell proliferation by epidemiological data as well as in vitro and in vivo studies. However, no clinical trials have been conducted with O. umbellatum constituents specifically for oncological indications.
Evidence strength: Preclinical (in vitro) only. No human data exist. Results cannot be extrapolated to clinical benefit or safety in humans.
5. Body Systems and Health Areas of Association
- Cardiovascular system: The primary pharmacologically active constituents — cardiac glycosides — act on the heart via Na⁺/K⁺-ATPase inhibition, producing digitalis-like effects. Historical interest in CHF was based on this pharmacology, but no modern clinical evidence supports therapeutic use.
- Emotional and psychological health: Star of Bethlehem is associated, within the Bach flower remedy tradition, with shock, grief, acute emotional trauma, bereavement, PTSD, and states of emotional numbness. There is a long-standing tradition of its use among practitioners of Bach Flower Remedies, who recommend Star of Bethlehem for individuals recovering from emotional shocks or trauma, including abuse.
- Gastrointestinal system: In homeopathic tradition, the plant is associated with epigastric pain, pyloric dysfunction, gastric ulceration, and abdominal indurations. No clinical evidence supports these associations.
- Autonomic nervous system: One small pilot crossover trial explored the effect of Rescue Remedy (containing Star of Bethlehem) on cardiac autonomic balance. Results were too preliminary to draw conclusions.
- Oncology (preclinical): Constituent compounds, particularly convallatoxin, have shown in vitro cytotoxic activity; this is a research-level observation only.
6. Dosage Forms and Reported Dosages
It is important to distinguish dosage forms across the distinct traditions, as they differ radically in what is actually administered:
Bach Flower Essence Formulations
Commercial Bach preparations list Star of Bethlehem (Ornithogalum umbellatum) at a 5X HPUS dilution as the active ingredient. Labeled dosing is 2 drops directly on the tongue or added to a beverage, to be repeated as needed throughout the day. For children under 2, label instructions state: "ask a doctor before use."
For combination use, product labeling instructs: place 2 drops in water and sip at intervals; for combination use, add 2 drops of each essence (maximum 7 essences) into a mixing bottle containing still spring water, and take 4 drops 4 times a day.
In the Rescue Remedy trial by Yang and Wang (2012), the study used four drops of five flower essences (including Star of Bethlehem) dissolved in brandy and 250 ml of distilled water. The placebo consisted of four drops of brandy in 250 ml of distilled water.
Homeopathic Dilutions
In classical homeopathic practice, a single dose of mother tincture is recommended and then the practitioner awaits action. Dosage of single homeopathic medicines varies depending upon the condition, age, and sensitivity. In some cases they are given as 3–5 drops 2–3 times a day, whereas in other cases they are given only once in a week, month, or even longer period. Commercial homeopathic preparations of O. umbellatum are also available at 6C, 30C, 200C, 1M, and 10M dilutions.
Botanical Extract (Crude Plant Material)
No standardized, approved dosage for crude botanical preparations of O. umbellatum is recognized by any major regulatory body. Historical pharmacological investigations conducted by Waud (1954) and Vogelsang (1955, 1961) used extracted preparations standardized against digitalis, but those studies predate modern clinical trial standards and no dosing protocol derived from them has been validated or approved. Given the plant's toxicity profile, no safe dose range for crude preparations has been established.
7. Safety Considerations and Interactions
Toxicity of Crude Plant Material
Star of Bethlehem (Ornithogalum umbellatum) is a plant whose bulb contains chemicals called toxic cardiac glycosides, which can lead to death when consumed. When taken by mouth, Star of Bethlehem is likely unsafe. It contains chemicals called toxic cardiac glycosides. Consuming Star of Bethlehem can lead to serious side effects, including death.
The cardiac glycosides in Star of Bethlehem can cause harm, including death. Plants containing cardiac glycosides are among some of the most toxic plants and have a narrow margin of safety.
Animal toxicity data are substantial. All parts of Star of Bethlehem are highly toxic to horses, due to the presence of cardiac glycosides, primarily convallatoxin and convalloside. Cardiac glycosides affect the heart and will specifically disrupt the horse's heart rhythm, which causes damage to multiple systems throughout the body. The bulbs appear to be the most toxic and result in rapid death of animals, particularly sheep, that consume them. Members of the genus Ornithogalum are some of the most poisonous plants found in South Africa.
O. umbellatum contains colchicine or structurally similar compounds, and children have been poisoned by eating the onion-like bulbs. This is a documented poisoning risk, as the bulbs may be confused with edible species such as wild garlic or onion.
Organ System Toxicity Beyond the Heart
Cardiac glycosides affect other organ systems such as the gastrointestinal, neurological, and visual systems. They inhibit the Na⁺,K⁺-ATPase ion pump found in the cell membrane of all mammalian cells, including retinal cells and the non-pigmented epithelial cells of the ciliary body. The presence of cardiac glycosides could explain visual impairment seen in reported toxicity cases. Digoxin, a well-known cardiac glycoside, induces cone dysfunction in canines at therapeutic dosages, and causes retinal degeneration and loss of vision in mice at high doses.
Drug Interactions (Inferred from Pharmacological Class)
Most plants containing cardiac glycosides are structurally similar to the cardiac drug digoxin, allowing for cross-reactivity. By pharmacological inference, crude extracts of O. umbellatum would be expected to carry the same interaction risks as digoxin, which include interactions with antiarrhythmic agents, diuretics (through electrolyte disturbances), calcium channel blockers, and drugs affecting P-glycoprotein. These interactions have not been formally characterized for O. umbellatum in controlled human studies.
Safety of Homeopathic/Flower Essence Preparations
The extreme dilution in flower essence and homeopathic preparations (5X HPUS or higher) is such that, at the molecular level, little or no pharmacologically active material is present. Most of the available evidence regarding the efficacy and safety of Bach flower remedies has a high risk of bias. Based on the reported adverse events in clinical trials, Bach flower remedies are probably safe. The safety concern associated with Star of Bethlehem applies specifically to crude plant material, not to highly diluted homeopathic or Bach flower essence products, which contain negligible amounts of the source material.
Regulatory Status
The Bach Original Flower Remedies Star of Bethlehem product is categorized as a human OTC drug with the marketing status of "unapproved homeopathic." This homeopathic product has not been evaluated by the Food and Drug Administration for safety or efficacy. The FDA is not aware of scientific evidence to support homeopathy as effective. Flower remedies are marketed as food supplements in some markets, which avoids legal efficacy requirements.
Pregnancy
Regarding pregnancy and breast-feeding: it is unsafe to take Star of Bethlehem crude plant material whether pregnant or not. The cardiac glycosides in Star of Bethlehem can cause harm, including death. Commercial Bach flower essence labels carry a precautionary statement: if pregnant or breast-feeding, ask a health professional before use.
Summary of Evidence Quality
The state of clinical evidence for Star of Bethlehem across all its areas of use can be summarized as follows. For use as a crude botanical extract in congestive heart failure, there are only mid-20th-century preliminary observations and no modern randomized controlled trials. For use as a Bach flower remedy in emotional trauma, grief, and anxiety, multiple systematic reviews of randomized trials — searching MEDLINE, Embase, AMED, and the Cochrane Library — have concluded that all placebo-controlled trials failed to demonstrate significant efficacy of flower remedies, and that the evidence does not support claims of clinical effectiveness for flower remedies. For gastrointestinal indications in homeopathy, no controlled human evidence exists. In all areas, the quality of evidence is either absent or very low by GRADE criteria. The pharmacological activity of the plant's constituents in preclinical models is well-characterized, but this has not translated into validated clinical benefit.
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