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How to Avoid “Lime” Disease

Do you make fresh lemonade? Do you squeeze fresh lemon on your fish? Do you enjoy fruity cocktails garnished with lime? If so, you may be at risk of developing an unsightly skin rash. Phytophotodermatitis (“phyto” refers to plants, “photo” to light, and “dermatitis” to skin inflammation) is a common condition that can develop when you touch coumarins, natural plant compounds, and then spend time in the sun.

Coumarins are found in many plants, including limes, lemons, celery, parsley, fennel, dill, and figs.

In the sun, a chemical reaction occurs in the skin that can lead to redness, swelling, and blistering — very similar to sunburn — that can sting, burn, or itch. Unlike a sunburn, however, the rash occurs only in spots that come into contact with the plant — say you squeeze a fresh lemon and the juices and oils from the rind drip or splatter onto your skin, or you touch your face with the hand that was squeezing the fruit. If you happen to go out into the sun before you wash off the drips, the skin in these areas may turn red and even blister. After the blisters heal, the spots can turn brown and take months to fade. So the next time you make lemonade, mix cocktails, or prepare a meal, remember the following advice:


  • If you touch fruits and veggies containing high levels of coumarins just before going out in the sun, wash your hands first and don’t touch your face or skin before you make it to the sink.
  • The rind of a fruit, rather than the juice, is more likely to cause this reaction. If you roll lemons or limes in your hands to get them them to release more juice, be sure to wash your hands before touching your face, even if you didn't touch the juice itself.
  • UVA-blocking sunscreen may help prevent phytophotodermatitis because it’s mainly these rays that react with the plant compounds. Your sunscreen should already have UVA protection, to fight sun damage.


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