Sheep sorrel

  • Allergen search puff


    Search ImmunoCAP allergens and allergen components. Note that all information is in English.

Code: w18
Latin name: Rumex acetosella
Source material: Pollen
Family: Polygonaceae
Common names: Sheep Sorrel, Field Sorrel, Red Sorrel, Common Sheep Sorrel

See also: Yellow dock w23 (R. crispus)

Allergen Exposure

Sheep sorrel is a perennial herb/weed that originated in Europe and Asia and has become naturalised throughout temperate North America and all other temperate regions across the world. Although grown as an herb, it is also classified as a noxious and invasive weed.

Sheep sorrel is a rhizomatous herb/weed that sometimes forms dense colonies by adventitious shoots from widely spreading roots and rhizomes. Stems are erect, slender, and 10 to 60cm tall. The arrowhead-like mid-green to dark-green fleshy leaves are 2 to 10cm long and 1 to 2cm wide and are situated mostly at the stem base. The leaves are spicy and pungent to the taste and often turn red in autumn.

The plant produces tiny flowers in spring and summer, which are borne in slender, loose, panicled racemes at the end of stalks. The plant is dioecious (male and female flowers are borne on separate plants); male flowers are orange-yellow; female flowers are red-orange. Sheep Sorrel is wind-pollinated, shedding copious amounts of pollen. The pollen is dominant in the autumn. The seed is an achene and is dispersed by wind and insects. Sheep sorrel reproduces by seed or from creeping roots and rhizomes.

Sheep sorrel is common in lawns, fields, pastures, meadows and waste places, and along roadsides.

Sheep sorrel leaves are used in soups and salads, and can be chewed to quench thirst. They have also been used as herbal medication. Sheep sorrel contains selenium and oxalic acid, both of which can be poisonous in large quantities.

Allergen Exposure

No allergens from this plant have yet been characterised.

Potential Cross-Reactivity

An extensive cross-reactivity among the different individual species of the genus could be expected, as well as to a certain degree among members of the family Polygonaceae.  (1)

Clinical Experience

IgE mediated reactions

Sheep sorrel pollen can induce asthma, allergic rhinitis and allergic conjunctivitis. (2, 3, 4, 5)

In Poland, examination of the records of 8,576 patients with “upper airway” allergy documented hypersensitivity to weed pollen allergens in 12.5%, the most prevalent sensitisation being to Wormwood (86.2%), Mugwort (82.9%), White Goosefoot (44.3%) and Sheep Sorrel (19.0%). Hypersensitivity to grass, tree and/or shrub pollens coexisted in 85.5%. (2) Sorrel has been shown to also be important pollen in eastern Poland. (6)

Sheep Sorrel pollen has also been shown to be a common aeroallergen in London, Leiden, Brussels, Munich and Marseilles (7), as well as in Athens (8) and Zurich. (9) Pollen from the Rumex species has been recorded as a significant aeroallergen in Salamanca (10), Murcia (11) and Seville, (12) Spain, but was found to be in low concentrations in the atmosphere in Madrid. (13)

Various studies in North America have demonstrated the presence of Rumex pollen: in the Tampa Bay area, Florida, (14) the Gulf Coast, (15) Anchorage, Alaska, (16) Philadelphia, Pennsylvania, and Cherry Hill, New Jersey. (17) In a study in Westchester County in the state of New York of skin prick tests to 48 aeroallergens in100 patients referred for allergic rhinitis, 3% had a positive skin prick test for Sorrel. (18) In a study examining the prevalence of positive skin test responses in a symptomatic military population of 1137 patients aged 4-79 years old who underwent a standard skin-prick testing panel of 53 aeroallergens, 18% were positive to Dock / Sorrel. (19)

In this study of pollen allergy in Taiwan, 419 patients with clinically diagnosed allergic rhinitis were enrolled and sensitisation to 30 allergens assessed by skin prick testing. A total of 313 (74.7%) had a positive skin test. The most common pollen allergens were spiny pigweed, Johnson grass, and sheep sorrel. (20) Sheep sorrel has also been documented to be an aeroallergen in Japan. (21)

Rumex pollen has been documented as an important aeroallergen in La Laguna City, Tenerife, in the Canary Islands (22), Dehra Dun, India (23) and Korea. (24)

The most prevalent aeroallergens was assessed in Mashhad City, the second largest city in Iran. Skin prick tests were performed with 27 common regional aeroallergens in 311 patients with allergic rhinitis. Forty three percent of patients were sensitised to Sheep sorrel. (25)

Rumex crispus, a member of the family, was detected in a sandstorm in Riyadh, Saudi Arabia. Sandstorms are potential triggers of asthma. (26) Other close relatives, Rumex vesicarius (27) and Rumex acetosa (28) (garden sorrel), have been shown to be important aeroallergens.

Other reactions

Fatal oxalic acid poisoning from Sorrel soup has been reported. (29)

Compiled by Dr Harris Steinman, harris@allergyadvisor.comUpdated: 30/09/2008


  1. Yman L. Botanical relations and immunological cross-reactions in pollen allergy. 2nd ed. Pharmacia Diagnostics AB. Uppsala. Sweden. 1982: ISBN 91-970475-09.
  2. Gniazdowska B, Doroszewska G, Doroszewski W. Hypersensitivity to weed pollen allergens in the region of Bygdoszcz. [Polish] Pneumonol Alergol Pol 1993;61(7-8):367-72.
  3. Solomon WR. An appraisal of Rumex pollen as an aeroallergen. J Allergy 1969;44(1):25-36.
  4. Larenas Linnemann D, Arias Cruz A, Guidos Fogelbach GA, Cid del Prado ML. Allergens used in skin tests in Mexico. [Spanish] Rev Alerg Mex 2009;56(2):41-7.
  5. Berna Dursun A, Celik GE, Alan S, Münevver Pinar N, Mungan D, Misirligil Z. Regional pollen load: effect on sensitisation and clinical presentation of seasonal allergic rhinitis in patients living in Ankara, Turkey. Allergol Immunopathol (Madr) 2008;36(6):371-8.
  6. Weryszko-Chmielewska E, Piotrowska K. Airborne pollen calendar of Lublin, Poland. Ann Agric Environ Med 2004;11(1):91-7.
  7. Spieksma FT, Charpin H, Nolard N, Stix E. City spore concentrations in the European Economic Community (EEC). IV. Summer weed pollen (Rumex, Plantago, Chenopodiaceae, Artemisia), 1976 and 1977. Clin Allergy 1980;10(3):319-29.
  8. Apostolou EK, Yannitsaros AG. Atmospheric pollen in the area of Athens. Acta Allergol 1977;32(2):109-17.
  9. Helbling A, Leuschner RM, Wuthrich B. Pollinosis. IV. Which pollens should be tested in allergology practice? Results of determinations of allergy-causing pollens in the Zurich air 1981-1984, with reference to threshold concentrations. [German] Schweiz Med Wochenschr 1985;115(34):1150-9.
  10. Hernandez Prieto M, Lorente Toledano F, Romo Cortina A, Davila Gonzalez I, Laffond Yges E, Calvo Bullon A. Pollen calendar of the city of Salamanca (Spain). Aeropalynological analysis for 1981-1982 and 1991-1992. Allergol Immunopathol (Madr) 1998;26(5):209-22.
  11. Munuera Giner M, Garcia Selles J. Allergenic pollens in south-east Spain. Allergy 2002;57(1):59-60.
  12. Gonzalez Minero FJ, Candau P, Tomas C, Morales J. Daily variation patterns of airborne allergenic pollen in southwestern Spain. J Investig Allergol Clin Immunol 1998;8(2):89-93.
  13. Subiza J, Jerez M, Jimenez JA, Narganes MJ, Cabrera M, Varela S, Subiza E. Allergenic pollen pollinosis in Madrid. J Allergy Clin Immunol 1995;96(1):15-23.
  14. Bucholtz GA, Lockey RF, Wunderlin RP, Binford LR, Stablein JJ, Serbousek D, Fernandez-Caldas E. A three-year aerobiologic pollen survey of the Tampa Bay area, Florida. Ann Allergy 1991;67(5):534-40.
  15. Lewis WH, Dixit AB, Wedner HJ. Aeropollen of weeds of the western United States Gulf Coast. Ann Allergy 1991;67(1):47-52.
  16. Anderson JH. Allergenic airborne pollen and spores in Anchorage, Alaska. Ann Allergy 1985;54(5):390-9.
  17. Dvorin DJ, Lee JJ, Belecanech GA, Goldstein MF, Dunsky EH. A comparative, volumetric survey of airborne pollen in Philadelphia, Pennsylvania (1991-1997) and Cherry Hill, New Jersey (1995-1997). Ann Allergy Asthma Immunol 2001;87(5):394-404.
  18. Basak P, Arayata R, Brensilver J Prevalence of specific aeroallergen sensitivity on skin prick test in patients with allergic rhinitis in Westchester County. Internet J Asthma Allergy Immunol 2008;6(2).
  19. Calabria CW, Dice JP, Hagan LL. Prevalence of positive skin test responses to 53 allergens in patients with rhinitis symptoms. Allergy Asthma Proc 2007;28(4):442-8.
  20. Liang KL, Su MC, Shiao JY, Wu SH, Li YH, Jiang RS. Role of pollen allergy in Taiwanese patients with allergic rhinitis. J Formos Med Assoc 2010 Dec;109(12):879-85.
  21. Suzuki Y, Ohta N, Sakurai S, Aoyagi M, Fukase S. Examination about positive ratio of pollen antigens by scratch test. [Japanese] Arerugi 2009;58(12):1619-28.
  22. Garcia Cobaleda I, De la Torre Morin F, Garcia Robaina JC, Hardisson de la Torre A. The capturing of pollens in the atmosphere of La Laguna City, Tenerife, Canary Islands 1990-1995. Allergol Immunopathol (Madr) 1997;25(6):272-9.
  23. Singh BP, Singh AB, Nair PK, Gangal SV. Survey of airborne pollen and fungal spores at Dehra Dun, India. Ann Allergy 1987;59(3):229-34.
  24. Jae-Won Oh, Ha- Baik Lee, Im-Joo Kang, Seong-Won Kim, Kang-Seo Park, et al. The revised edition of Korean calendar for allergenic pollens. Allergy Asthma Immunol Res 2011 Sep;3:e65.
  25. Fereidouni M, Farid Hossini R, Jabbari Azad F, Ali Assarezadegan M, Varasteh A. Skin prick test reactivity to common aeroallergens among allergic rhinitis patients in Iran. Allergol Immunopathol (Madr) 2009;37(2):73-9.
  26. Kwaasi AA, Parhar RS, al-Mohanna FA, Harfi HA, Collison KS, al-Sedairy ST. Aeroallergens and viable microbes in sandstorm dust. Potential triggers of allergic and nonallergic respiratory ailments. Allergy 1998;53(3):255-65.
  27. Hasnain SM, Fatima K, Al-Frayh A, Al-Sedairy ST. One-Year pollen and spore calendars of Saudi Arabia Al-Khobar, Abha and Hofuf Aerobiologia 2005;21(3):241-7.
  28. Pelikan Z. Asthmatic response induced by nasal challenge with allergen. Int Arch Allergy Immunol 2008 Nov 11;148(4):330-8.
  29. Farre M, Xirgu J, Salgado A, Peracaula R, Reig R, Sanz P. Fatal oxalic acid poisoning from sorrel soup. Lancet 1989;2(8678-8679):1524.


As in all diagnostic testing, the diagnosis is made by the physican based on both test results and the patient history.