Background

• Water hemlock grows in temperate wet, marshy areas in mainly North America. According to the U. S. Department of Agriculture (USDA), "water hemlock is the most violently toxic plant that grows in North America."
• Water hemlock is sometimes mistaken for parsnips, due to the similar appearance of their white tuberous roots.
• Although water hemlock was rarely used for headache according to traditional use, there is insufficient available evidence in humans or animals to support the use of water hemlock for any indication.

References

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• Carlton BE, Tufts E, Girard DE. Water hemlock poisoning complicated by rhabdomyolysis and renal failure. Clin.Toxicol. 1979;14(1):87-92.
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• From the Centers for Disease Control and Prevention. Water hemlock poisoning--Maine, 1992. JAMA 5-18-1994;271(19):1475.
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• Haupt H. [Poisonous and less poisonous plants. Conium maculatum and Cicuta virosa]. Kinderkrankenschwester. 2003;22(11):495-496.
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• Heath KB. A fatal case of apparent water hemlock poisoning. Vet.Hum.Toxicol. 2001;43(1):35-36.
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• Knutsen OH. Paszkowski P. New aspects in the treatment of water hemlock poisoning. J.Toxicol.Clin.Toxicol. 1984;22(2):157-166.
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• Koloshtivina OV. [Poisonings of children by water hemlock]. Med.Sestra. 1980;39(10):37-38.
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• Landers D, Seppi K, Blauer W. Seizures and death on a white river float trip. Report of water hemlock poisoning. West J.Med. 1985;142(5):637-640.
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• Lkhagvazhav Kh, Biambasuren Ch, Maslov AV. [Group poisoning by water hemlock]. Sud.Med.Ekspert. 1980;23(3):51-52.
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• Mack RB. Keats, Socrates and fool's parsley--water hemlock poisoning. N.C.Med.J. 1985;46(3):163-164.
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• Muratova LM. [Providing aid before the hospital stage to children with water hemlock poisoning]. Feldsher.Akush. 1981;46(5):38-40.
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• Rizzi D, Basile C, Di Maggio A, et al. Clinical spectrum of accidental hemlock poisoning: neurotoxic manifestations, rhabdomyolysis and acute tubular necrosis. Nephrol.Dial.Transplant. 1991;6(12):939-943.
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• Short J. Water hemlock poisoning. Emerg.Nurse 2006;14(7):18-19.
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• van Heijst AN, Pikaar SA, van Kesteren RG, et al. [Poisoning due to water hemlock (Cicuta virosa)]. Ned.Tijdschr.Geneeskd. 12-31-1983;127(53):2411-2413.
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• Water hemlock poisoning--Maine, 1992. MMWR Morb.Mortal.Wkly.Rep. 4-8-1994;43(13):229-231.
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