Skip to main content

Queen's Delight

Scientific Name(s): Stillingia sylvatica Garden ex L.
Common Name(s): Cockup-hat, Indian flea root, Marcory, Nettle potato, Queen's delight, Queen's root, Silverleaf, Stillingia, Yaw-root

Medically reviewed by Last updated on Aug 30, 2021.

Clinical Overview


No pharmacologic studies have been reported on whole plant extracts.The chemical constituent prostratin is of research interest for chemotherapeutic effects.


There is no clinical evidence to support specific dosage recommendations for queen's delight.


No longer considered safe.


Documented adverse effects. Not to be used while nursing. Avoid use.


None well documented.

Adverse Reactions

Information is lacking. Stillingia root is a purgative and irritant product that should be avoided.


Information is lacking. The presence of phorbols (protein kinase C activator) suggests mutagenicity is possible.

Scientific Family

  • Euphorbiaceae (spurge)


Queen's delight is a perennial herb that grows in the sandy soils of pine barrens from Texas and Oklahoma east to Virginia and Florida.(USDA 2021) When broken, the stems exude an acrid white sap, as do many spurges. The small yellowish flowers are borne on a terminal spike, with the few female flowers at the base below the more numerous male flowers. The three-chambered seedpod forcibly ejects the ripe seed. The rootstock and rhizome are large and woody. The scientific name honors the English botanist A.B. Stillingfleet. The genus was monographed in 1951.(Rogers 1951) Oil of stillingia is a fixed oil derived from the Chinese tree Sapium sebiferum, which was formerly classified as a species of Stillingia.(Aitzmetmuller 1992)


American Indians used the root to repel fleas; Creek Indian women were reported to consume the boiled, mashed roots after giving birth.Altschul 1977, Krochmal 1973 The root was used in the southern United States for constipation, as a purgative, and to treat syphilis and liver, skin, and lung diseases.Krochmal 1973 The dried root is considered to be less toxic than the fresh root. Stillingia was used by the Eclectic medical movement and is an optional ingredient in the controversial Hoxsey cancer formula.Hartwell 1982, Krochmal 1973 It has also been used in homeopathy. A number of 19th century studies were published on analysis of Stillingia root while the plant has been largely ignored recently, even though it remained in the National Formulary until 1947.Harmanson 1882, Youngken 1939


Chemical constituents of interest elucidated from the plant include gnidilatidin and gnidilatin, prostatin and prostratin, silvacrol, stillingia Factors s1-8, and stillingine.Adolf 1980, Duke 1992, Newall 1996 The plant contains an essential oil, protein, resin and tannin. Hydrogen cyanide has also been identified.Aitzmetmuller 1992, Duke 1992

Uses and Pharmacology

Studies have been conducted with prostratin.

Antiretroviral effects (of prostratin)

Animal and in vitro data

Prostratin has been identified in the plant, with synthetic versions of the protein kinase C activator being evaluated in studies. Prostratin appears to induce HIV expression from latent CD4+ T cells in HIV-infected individuals, with the potential to then enhance elimination, alone and in combination with other compounds.(Archin 2014, Beans 2013, Rochat 2017) Through activation of protein kinase C, it is able to inhibit HIV infection through downregulation of the HIV cellular entry receptors CD4 and CXCR4, and possibly CCR5.(Andersen 2018)

Chemotherapeutic effects (of prostratin)

Animal and in vitro data

Prostratin has been demonstrated to inhibit the growth of myeloid leukemia cells.(Shen 2015) In an in vitro study, prostratin was found to exert selective cytotoxicity against breast cancer cell lines. It inhibited CSCR4 expression through downregulation of SIK3 expression.(Alotaibi 2018)

Prostratin blocks HIV infection by downregulating the HIV cellular entry receptors CD4 and CXCR4, and possibly CCR5


There is no clinical evidence to support specific dosage recommendations for queen's delight. Classical use of queen's delight called for 2 g of the root, however the presence of irritant and potentially cytotoxic phorbol esters in this plant contraindicates therapeutic use.Adolf 1980

Pregnancy / Lactation

Documented adverse effects. Not to be used while nursing.McGuffin 1997 Avoid use.


None well documented. Caution may be warranted with concomitant anti-HIV medicines.

Adverse Reactions

Do not ingest or use topically in human medicine. Observe particular caution with the fresh root, which appears to be more toxic than the dried product. Stillingia root is a purgative and irritant product that should be avoided because of a high likelihood of tumor promotion and documented severe irritancy to skin.Adolf 1980


Information is lacking. The presence of phorbols (protein kinase C activator) suggests mutagenicity is possible.Adolf 1980



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.

Adolf W, et al. New irritant diterpene esters from roots of Stillingia sylvatica L. (Euphorbiaceae). Tetrahedron Lett 1980;21:2887-2890.
Aitzmetmuller K, et al. High-performance liquid chromatographic investigations of stillingia oil. J Chromatogr 1992;603:165-173.
Alotaibi D, Amara S, Johnson TL, Tiriveedhi V. Potential anticancer effect of prostratin through SIK3 inhibition. Oncol Lett. 2018; 15:3252-3258.29435066
Altschul SvR. Drugs and Foods from Little-known Plants. Notes in Harvard University Herbaria, 1977:165.
Andersen RJ, Ntie-Kangc F, Tietjend I. Natural product-derived compounds in HIV suppression, remission, and eradication strategies. Antiviral Res. 2018;158:63-77.30063970
Archin NM, Margolis DM. Emerging strategies to deplete the HIV reservoir. Curr Opin Infect Dis. 2014;27(1):29-35.24296585
Beans EJ, Fournogerakis D, Gauntlett C, et al. Highly potent, synthetically accessible prostratin analogs induce latent HIV expression in vitro and ex vivo. Proc Natl Acad Sci U S A. 2013;110(29):11698-703.
Duke J. Handbook of biologically active phytochemicals and their activities. Boca Raton, FL: CRC Press, Inc.; 1992.
Harmanson JH. The root of Stillingia sylvatica. Am J Pharm 1882;386-387.
Hartwell J. Plants Used Against Cancer. A Survey. Lawrence, MA: Quarterman Publications,1982:206.
Krochmal A, et al. A Guide to the Medicinal Plants of the United States. New York: Quadrangle, 1973:211.
McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press; 1997.
Newall CA, Anderson LA, Phillipson JD. Herbal medicines: A guide for health-care professionals. London: Pharmaceutical Press; 1996.
Rochat MA, Schlaepfer E, Speck RF. Promising role of toll-like receptor 8 agonist in concert with prostratin for activation of silent HIV. J Virol. 2017; 91:e02084-16.
Rogers DJ. A revision of Stillingia in the New World. Ann Mo Bot Gard 1951;38:207-259.
Shen X, Xiong GL, Jing Y, et al. The protein kinase C agonist prostratin induces differentiation of human myeloid leukemia cells and enhances cellular differentiation by chemotherapeutic agents. Cancer Lett. 2015;356(2 Pt B):686-96.25449427
USDA, NRCS. 2021. PLANTS Database (, 08/28/2021). National Plant Data Team, Greensboro, NC 27401-4901 USA.
Youngken HW, et al. Studies of National Formulary drugs. Stillingia. J Am Pharm Assoc 1939;28:24-28.

Further information

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