Skip to main content


Scientific Name(s): Urginea indica (Roxb.) Kunth. (Indian squill), Urginea maritima (L.) Baker (European or white squill), Urginea maritima var. pancratium Stein Baker (red squill)
Common Name(s): European squill, Indian squill, Mediterranean squill, Red squill, Scilla, Sea onion, Sea squill, White squill

Medically reviewed by Last updated on Mar 1, 2022.

Clinical Overview


Squill is a cardiotonic similar to digitalis but is generally not used medicinally. Traditional uses include as a component of hair tonics to treat seborrhea and dandruff, and as a rodenticide. Clinical studies have evaluated use in alopecia and asthma; however, clinical data are lacking to recommend squill for any indication.


Clinical trials are lacking to provide dosing recommendations. Various preparations and formulations exist; strength of squill preparations and extracts may vary. As with any cardiac glycoside-containing product, use squill with caution.


Contraindications have not been identified.


Avoid use. Abortifacient effects and effects on the menstrual cycle have been documented.


None well documented.

Adverse Reactions

Adverse reactions include vomiting and convulsions, which generally are observed in overdose situations.


No data.

Scientific Family

  • Liliaceae (lily)


White squill is a perennial herb native to the Mediterranean region. It often grows in sandy soil near the sea, and its onion-like appearance accounts for the common names sea onion or sea squill; a synonym of U. maritima is D. maritima. The bulbous portion of the base is harvested, and the dried inner scales of the bulb (not the central portion of the bulb) is used. White squill has sometimes been adulterated by the inclusion of Indian squill, which has comparable biological activity.(Deb 1976) Red squill is primarily used as a rodenticide.(USDA 2022)


Some varieties of squill have been used as rodenticides for more than 1,000 years. Extracts of the bulb were traditionally used as a cardiotonic for the treatment of edema (by the Romans and ancient Egyptians), as an expectorant, and as an emetic. Use as an expectorant in some commercial cold preparations has continued. Because of the popularity of the digitalis glycosides, squill components are rarely used in the United States as cardioactive agents; squill was approved by the German Commission E (revised 1989) for mild cardiac insufficiency and diminished kidney capacity.(Stein 2004) Squill and squill formulations are widely used in Iranian traditional medicine, most commonly for respiratory disorders (ie, pneumonia, chronic bronchitis, asthma).(Nejatbakhsh 2017) Squill has been used traditionally as a cancer remedy.(Duke 1985)


Squill contains a large number of related steroidal cardioactive glycosides. Those found in the greatest concentration in the bulb include scillaren A and proscillaridin A, the aglycone of both being scillarenin. In addition, glucoscillaren A, scillaridin A, and scilliroside have been characterized. In one study, the most common components identified in dried bulbs were scilliroside (approximately 45 ppm) and scillaren A (approximately 38 ppm)(Balbaa 1979); other studies have found proscillaridin A in the greatest concentration.(Garcia Casado 1977) Scillaren B refers to a mixture of squill glycosides.(Leung 1980) Components of squill tissue cultures appear to vary in quantitative composition from whole bulb extracts.(Shyr 1976) Furthermore, extracts from fresh bulbs can vary based on the time of year they are collected. Many novel cardiac glycosides have been isolated and identified from squill.(Iizuka 2001, Kopp1996, Krenn 1996, Krenn 2000) Indian squill also contains proscillaridin A and scillaren A as major glycosides, with minor components differing from white squill.(Jha 1981) Glycosides of red squill also have been studied.(Balbaa 1979, Verbiscar 1986) Other constituents found in squill include flavonoids,(Fernandez 1972, Fernandez 1975) the fructan sinistrin,(Spies 1992) and related carbohydrates(Praznik 1993) and an antifungal glycoprotein.(Deepak 2003)

Uses and Pharmacology

Methanolic extracts of red squill have been used as hair tonics in treating seborrhea and dandruff, the activity being ascribed to scilliroside.(Leung 1980)

In general, red squill is not used medicinally; the powdered dried bulbs of red squill are mainly used as rodenticides. Death is caused by the centrally induced convulsant action of scilliroside, rather than by direct cardiotoxicity. Rats lack a vomit reflex and are insensitive to the emetic action of these glycosides. Because squill-laced bait is vomited by domestic animals before a lethal dose can be absorbed, often it is considered to be a rat-specific agent.(Balbaa 1979)


Clinical data

A double-blind, randomized study compared the effects of white squill (U. maritima) 2% and clobetasol propionate 0.05% lotions in 42 patients in Iran who presented to the hospital with alopecia areata. Patients (72% male) were at least 6 years of age (mean age, 29 years; range, 9 to 52 years) with scalp alopecia and at least 25% scalp hair loss. Squill or clobetasol lotion was topically applied twice daily for 12 weeks. Compared with clobetasol, squill significantly increased overall hair regrowth scores by month 2 of treatment (P=0.000); by month 3, the percentage of patients experiencing more than 75% growth was significantly greater in the squill group (23.3% vs 9.6%; P<0.05). Rate of mean hair growth and vellus hair growth, as well as mean size of the affected areas and satisfaction rates, were similar between groups at month 3.(Moosavi 2020)


Animal data

Rheumatoid arthritis and inflammatory paw edema were attenuated by U. indica ethanolic and aqueous extracts (3% and 3.5%, respectively) in a variety of acute and chronic inflammation rat models. At day 23, reduction in arthritic development by the extracts and the positive control, piroxicam, were significant compared with controls, with the ethanolic extract performing similar to piroxicam (P<0.001 for all 3 treatments). Similar significant results were observed for suppression of paw edema.(Akhtar 2019)


Animal data

Studies in rat tissues indicate a bronchodilatory effect of U. maritima extract via beta-2 receptor stimulation, muscarinic receptor inhibition, calcium channel blocking, and potassium channel opening mechanisms. Effects of the extract were comparable with that of theophylline.(Kazemi Rad 2021)

Clinical data

In a triple-blind, randomized, placebo-controlled trial, effects of adjunctive squill vinegar syrup (Squill Oxymel) use was investigated in adult Iranian patients with moderate to severe persistent asthma (forced expiratory volume in the first second of expiration [FEV1] less than 80% predicted) (N=60). Squill vinegar syrup, simple vinegar syrup, or placebo was consumed at a dose of 10 mL twice daily for 6 weeks as add-on to routine treatment (ie, for at least the past 6 months) with high-dose combination inhaled corticosteroids (fluticasone or budesonide) and long-acting beta-agonists. Significant improvement was observed with squill vinegar syrup in multiple spirometry parameters (ie, FEV1, percent FEV1, percent FEV1/forced vital capacity [FVC]) compared with the other 2 groups, while both the squill vinegar syrup and simple vinegar syrup resulted in higher respiratory questionnaire scores than placebo (P<0.001 for both). No significant differences in plethysmography parameters were observed among groups. Mild nausea and vomiting were reported in the squill vinegar syrup and simple vinegar syrup groups (n=2 and n=3, respectively).(Nejatbakhsh 2017)


In vitro data

An in vitro study showed that proscillaridin A, a cardiac glycoside constituent of U. maritima, inhibited proliferation and induced apoptosis in prostate cancer cells in a dose-dependent manner; furthermore, proscillaridin A inhibited Jak2/STAT3 signalling and augmented doxorubicin toxicity.(He 2018)

Cardiovascular effects

Squill glycosides have cardiotonic properties similar to digitalis. However, squill components are generally poorly absorbed from the GI tract and are less potent than digitalis.(Duke 1985)

Animal and in vitro data

Animal and in vitro studies evaluating white squill extract have demonstrated positive inotropic effects (in isolated rabbit atrium) but also negative chronotropic effects (in experimental rats).(Dizaye 2010) Squill extracts caused peripheral vasodilation and bradycardia in anesthetized rabbits.(Shyr 1976)


Clinical data

In a triple-blind, randomized, 2-group controlled trial in postmenopausal women (N=60), an oil extract of squill used topically 2 to 3 times weekly for 4 weeks decreased dyspareunia compared with placebo (olive oil); however, the study had multiple limitations.(Karimi 2021)


Clinical trials are lacking to provide dosing recommendations.

Various squill preparations and formulations exist; strength of preparations and extracts may vary. As with any cardiac glycoside-containing product, use squill with caution.

Squill vinegar syrup at a dosage of 10 mL twice daily for 6 weeks (as add-on to routine asthma treatment) was evaluated in a small study of patients with stable moderate to severe persistent asthma.(Nejatbakhsh 2017)

Preparations for oral administration are enteric coated to prevent degradation by gastric acid. Meproscillaren, a semisynthetic derivative of proscillaridin, is absorbed orally and may be effective in certain individuals.(Bayazit 2010)

Pregnancy / Lactation

Avoid use. Abortifacient effects and effects on the menstrual cycle have been documented.(Newall 1996)


Use caution when coadministered with calcium, laxatives, quinidine, saluretics, and extended glucocorticoid therapy.

Adverse Reactions

Adverse reactions related to squill include vomiting and convulsions, which generally are observed in overdose situations. In general, red squill is not used medicinally and may induce convulsions.

A pilot study on the effect of squill in asthma reported mild nausea and vomiting among some participants.(Nejatbakhsh 2017)


Although white squill and its extracts have the potential to induce life-threatening cardiac effects in relatively low doses, they generally have not been associated with human toxicity. Vomiting often is induced as a reflex in cases of overdosage, minimizing the absorbed dose. The toxic dose of squill soft mass (a galenical extract form used to make certain squill preparations) in guinea pigs is 270 mg/kg; tinctures made from Indian squill caused death at a dose of 36 mg/kg.(Hakim 1976a, Hakim 1976b) Fresh bulbs contain a vesicant.(Duke 1985)

Index Terms

  • Drimia maritima



This information relates to an herbal, vitamin, mineral or other dietary supplement. This product has not been reviewed by the FDA to determine whether it is safe or effective and is not subject to the quality standards and safety information collection standards that are applicable to most prescription drugs. This information should not be used to decide whether or not to take this product. This information does not endorse this product as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this product. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this product. This information is not specific medical advice and does not replace information you receive from your health care provider. You should talk with your health care provider for complete information about the risks and benefits of using this product.

This product may adversely interact with certain health and medical conditions, other prescription and over-the-counter drugs, foods, or other dietary supplements. This product may be unsafe when used before surgery or other medical procedures. It is important to fully inform your doctor about the herbal, vitamins, mineral or any other supplements you are taking before any kind of surgery or medical procedure. With the exception of certain products that are generally recognized as safe in normal quantities, including use of folic acid and prenatal vitamins during pregnancy, this product has not been sufficiently studied to determine whether it is safe to use during pregnancy or nursing or by persons younger than 2 years of age.

Akhtar G, Shabbir A. Urginea indica attenuated rheumatoid arthritis and inflammatory paw edema in diverse animal models of acute and chronic inflammation. J Ethnopharmacol. 2019;238:111864. doi:10.1016/j.jep.2019.11186430970284
Balbaa SI, Khafagy SM, Khayyal SE, Girgis AN. TLC-spectrophotometric assay of the main glycosides of red squill, a specific rodenticide. J Nat Prod. 1979;42(5):522-524. doi:10.1021/np50005a013521820
Bayazit V, Knar V. Analgesic effects of scilliroside, proscillaridin-A and taxifolin from squill bulb (Urginea maritima) on PAINS. Dig J Nanomaterials & Biostructures. 2010;5(2):457-465.
Deb DB, Dasgupta S. Studies on Indian squill — Urginea indica (Roxb.) Kunth. Q J Crude Drug Res. 1976;14:49-60.
Deepak AV, Thippeswamy G, Shivakameshwari MN, Salimath BP. Isolation and characterization of a 29-kDa glycoprotein with antifungal activity from bulbs of Urginea indica. Biochem Biophys Res Commun. 2003;311(3):735-742. doi:10.1016/j.bbrc.2003.10.05614623334
Dizaye K, Hamad, AK. Cardiovascular studies of white squill (Urginea maritima) extract. Zanco J Med Sci. 2010;14(1):20-27.
Duke JA. Handbook of Medicinal Herbs. CRC Press; 1985.
Fernandez M, Renedo J, Arrupe T, Vega FA. C-Glycosylflavones in the bulbs of squill. Phytochemistry. 1975;14:586.
Fernandez M, Vega FA, Arrupe T, Renedo J. Flavonoids of squill, Urginea maritima. Phytochemistry. 1972;11:1534.
Garcia Casado P, Renedo MJ, Fernández M, Vega FA. Proscillaridin A yield from squill bulbs. Pharm Acta Helv. 1977;52(9):218-221.
Hakim FS, Bowery NG, Evans FJ. Comparative potencies of European and Indian squill. J Pharm Pharmacol. 1976;28(1):81-82. doi:10.1111/j.2042-7158.1976.tb04034.x6663
Hakim FS, Evans FJ. The potency and phytochemistry of Indian squill soft extract. Pharm Acta Helv. 1976;51:117-118.967904
He Y, Khan M, Yang J, Yao M, Yu S, Gao H. Proscillaridin A induces apoptosis, inhibits STAT3 activation and augments doxorubicin toxicity in prostate cancer cells. Int J Med Sci. 2018;15(8):832-839.30008594
Iizuka M, Warashina T, Noro T. Bufadienolides and a new lignan from the bulbs of Urginea maritima. Chem Pharm Bull (Tokyo). 2001;49(3):282-286. doi:10.1248/cpb.49.28211253917
Jha S, Sen S. Bufadienolides in different chromosomal races of Indian squill. Phytochemistry. 1981;20:524-526.
Karimi F, Babazadeh R, Zojaji A, Jouya S. Squill oil for decreasing dyspareunia and increasing sexual satisfaction in menopausal women: a triple-blind randomized controlled trial. Avicenna J Phytomed. 2021;11(5):464-472. doi:10.22038/AJP.2021.1777734745918
Kazemi Rad H, Memarzia A, Amin F, Boskabady MH. Relaxant effect of Urginea maritima on tracheal smooth muscle mediated by the effect on beta-2 adrenergic, muscarinic receptors and calcium and potassium channels. Evid Based Complement Alternat Med. 2021;2021:6637990. doi:10.1155/2021/663799033968155
Kopp B, Krenn L, Draxler M, et al. Bufadienolides from Urginea maritima from Egypt. Phytochemistry. 1996;42(2):513-522. doi:10.1016/0031-9422(95)00876-48688179
Krenn L, Jelovina M, Kopp B. New bufadienolides from Urginea maritima sensu strictu. Fitoterapia. 2000;71(2):126-129. doi:10.1016/s0367-326x(99)00142-210727807
Krenn L, Kopp B. 9-Hydroxyscilliphaeoside, a new bufadienolide from Urginea maritima. J Nat Prod. 1996;59(6):612-613.
Leung AY. Encyclopedia of Common Natural Ingredients Used in Food, Drugs, and Cosmetics. Wiley; 1980.
Moosavi ZB, Aliabdi M, Golfakhrabadi F, Namjoyan F. The comparison of therapeutic effect of Clobetasol propionate lotion and squill extract in alopecia areata: a randomized, double-blind clinical trial. Arch Dermatol Res. 2020;312(3):173-178. doi:10.1007/s00403-019-02004-w31707498
Nejatbakhsh F, Karegar-Borzi H, Amin G, et al. Squill oxymel, a traditional formulation from Drimia maritima (L.) Stearn, as an add-on treatment in patients with moderate to severe persistent asthma: a pilot, triple-blind, randomized clinical trial. J Ethnopharmacol. 2017;196:186-192. doi:10.1016/j.jep.2016.12.03227998692
Newall CA, Anderson LA, Phillipson JD, eds. Herbal Medicines: A Guide for Health-Care Professionals. Pharmaceutical Press; 1996.
Praznik W, Spies T. Fructo-oligosaccharides from Urginea maritima. Carbohydr Res. 1993;243(1):91-97. doi:10.1016/0008-6215(93)84083-i8324767
Shyr SE, Staba EJ. Examination of squill tissue cultures for bufadienolides and anthocyanins. Planta Med. 1976;29(1):86-90. doi:10.1055/s-0028-1097633943793
Spies T, Praznik W, Hofinger A, Altmann F, Nitsch E, Wutka R. The structure of the fructan sinistrin from Urginea maritima. Carbohydr Res. 1992;235:221-230. doi:10.1016/0008-6215(92)80090-n1473105
Stein RA, Oz MC, eds. Contemporary Cardiology Complementary and Alternative Cardiovascular Medicine. Humana Press Inc; 2004.
Urginea maritima (L.) Baker. USDA, NRCS. 2022. The PLANTS Database (, 20 January 2022). National Plant Data Team, Greensboro, NC 27401-4901 USA.
Verbiscar AJ, Patel J, Banigan TF, Schatz RA. Scilliroside and other scilla compounds in red squill. J Agr Food Chem. 1986;34:973-979.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.