phytophotodermatitis

medical condition

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Last updated

July 21, 2026

Quick Summary

Phytophotodermatitis is a skin reaction caused by a combination of plant chemicals and sunlight. The term breaks down as phyto (plant), photo (light), and dermatitis (skin inflammation). Certain plants contain furocoumarins, which are chemicals that make the skin more sensitive to ultraviolet (UV) light. When these chemicals contact the skin and are then exposed to sunlight, they can trigger a reaction that includes redness, swelling, and painful, itchy blisters. This reaction can resemble a severe sunburn and may leave dark patches on the skin that can last for weeks or months.1

While limes are a common cause, other plants like giant hogweed, celery, and figs can also trigger phytophotodermatitis. The severity of the reaction depends on the amount of plant chemical exposure and the intensity of UV light.1

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Can Limes Burn Your Skin?
…can trigger a reaction called phytophotodermatitis—phyto meaning “plant,” photo meaning “light,” and dermatitis meaning “skin inflammation.” The condition is caused by a class of plant chemicals known as furocoumarins (also called furanocoumarins), which are found in limes and a surprising number of other plants.
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…can trigger a reaction called phytophotodermatitis—phyto meaning “plant,” photo meaning “light,” and dermatitis meaning “skin inflammation.” The condition is caused by a class of plant chemicals known as furocoumarins (also called furanocoumarins), which are found in limes and a surprising number of other plants.
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hogweed
…leaves and sap can cause phytophotodermatitis, in which the skin erupts in severe blisters if exposed to sunlight; blindness can occur if the sap enters the eyes.
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…leaves and sap can cause phytophotodermatitis, in which the skin erupts in severe blisters if exposed to sunlight; blindness can occur if the sap enters the eyes.
Read More