The clear sap inside this plant’s hollow stem containsfurocoumarins, which can cause asunburn-like skin rash calledphytophotodermatitis.
Albert Fertl / Getty Images
What Exactly Is Phytophotodermatitis?
Reproduced with permission from DermNetwww.dermnetnz.org2023.
Albert Fertl / Getty Images
Phytophotodermatitis is a skin reaction sparked by contact with a plant containing light-activated chemical compounds.
Wild parsnip sap works the same way.
Any skin area this phototoxic sap touches becomes hypersensitive to sunlight.
Reproduced with permission from ©DermNetwww.dermnetnz.org2023.
Wild parsnip chemical burns occur when UVA light activates the furocoumarins in sap-touched patches of skin.
What Does Wild Parsnip Look Like?
It has a hollow, ridged stem that’s filled with phototoxic sap.
It may have a few small yellow flowers on top when it blooms during summer.
Wild parsnip rash usually starts out looking red and inflamed.
Blisters may form in the first week and can take several weeks to heal.
Wild parsnip burns can cause scars.
How to Treat Wild Parsnip Burns
Wild parsnip sap can cause first- or second-degree burns.
Where Does Wild Parsnip Grow?
Get inside as quickly as possible and wash your skin thoroughly with soap and water.
If possible, avoid abundant UV exposure for the next day or so.
Get inside and wash it off ASAP.
When wild parsnip is weed-whacked with a string trimmer or mowed, the sap can splatter everywhere.
Also, wearsunscreen or sunblockto minimize your skin’s photosensitivity.
Summary
Wild parsnip is a weed with poisonous sap that often grows along roads and paths.
When it blooms in summertime, it has pretty yellow flowers and can grow up to 5 feet tall.
Never pick these yellow wildflowers.
The good news is that wild parsnip sap needs sunlight to activate.
2021;24(1):14-23 doi:10.3831/KPI.2021.24.1.14
Walling AL, Walling HW.Phytophotodermatitis induced by wild parsnip.Dermatology Online Journal.
2018;24(2).
doi:10.5070/D3242038189
Hankinson A, Lloyd B, Alweis R.Lime-induced phytophotodermatitis.Journal of Community Hospital Internal Medicine Perspectives.
2021;34(2):398-401. doi:10.3122/jabfm.2021.02.200382
Minnesota Department of Agriculture.Wild parsnip.
New York Invasive Species (IS) Information.Wild parsnip.
UnityPoint Health.Summertime rashes: poison oak, poison ivy, and wild parsnips.
Iowa State University.Wild parsnip toxicity today’s fun fact.
Hammett E.The latest advice on burns.BDJ Team.
2019;6(10):16-18.
Venter THJ, Karpelowsky JS, Rode H.Cooling of the burn wound: the ideal temperature of the coolant.Burns.
2022;33:184-194. doi:10.1016/j.jpra.2022.05.004
Wisconsin Department of Natural Resources.Wild parsnip.
Oregon.gov.Burned by wild parsnip.
