It’s still summertime, and hopefully we are all taking care of our skin by using sunscreens and sun protection, avoiding insect bites, and treating occasional poison ivy. But there’s another common skin condition that we dermatologists see quite often during sunny weather: phytophotodermatitis. Never heard of it? We see quite a bit of it at SkinCare Physicians near Boston, and the main culprit is LIMES!
To better understand this condition, let’s break down the derivation of the word:
So, phytophotodermatitis means inflammation of the skin that is caused by exposure to certain plants in combination with sun exposure. Some plants contain light-sensitizing chemicals that cause blistering rashes or skin pigmentation after sun exposure.
The most common scenarios of exposure
One of the most common sources of phytophotodermatitis is from limes, which are commonly consumed in sunny climates! At SkinCare Physicians, we have seen many patients with this condition who have been exposed after squeezing a lime into a drink, but other patients have developed this condition after pressing limes to make a Key Lime pie, and we even saw one child recently who had been sucking on limes during a sunny vacation, developing a blistery and pigmented rash around his mouth! Children can also develop this condition after eating real juice lime popsicles that drip onto the skin in hot, sunny weather. Chefs and bartenders who might be catering in a sunny location and handling citrus fruits (or celery) are also at risk.
What does phytophotodermatitis look like
The oils from the rind of the lime contain light-sensitizing chemicals called furocoumarins. When these oils are deposited on the fingers after squeezing limes, the photosensitizing chemicals can be transferred to other areas on the body. Some patients report awakening with fingerprint-like or handprint-like marks on their body resembling bruises! Others report strange streaks on their hands or arms (where the lime juice may have dripped) or bizarre polka-dot like marks on their body (where the lime juice might have sprayed after squeezing).
The eruption may begin as a blistering rash, in essence a sunburn, in precisely the spots that were exposed to the lime juice. In many patients, the inflammation may be so mild that it is not even noticed until the puzzling pigmentation shows up on the skin a day or 2 later!
Other sources of exposure
Lime exposure in sunny climates is by far the most common scenario we see at SkinCare Physicians. But there are other plants that can cause this reaction: wild parsnip, parsley, and celery can cause this condition as well. Giant hogweed is of particular concern. The sap of this invasive plant can cause such severe phytophotodermatitis involving not only the skin, but also the eyes, that scarring and blindness has been reported.
How to avoid and treat phytophotodermatitis
The good news is that the rash and pigmentation of phytophotodermatitis will resolve spontaneously, but the best approach is to avoid it altogether! The chemicals that cause phytophotodermatitis are easily removed with simple soap and water.
Follow these tips:
If you have any concerns about a blistering or pigmented rash, contact your dermatologist at SkinCare Physicians, (617) 731-1600.
Finally, to remember this summer curse, just sing the following lyrics to the tune of Harry Nilsson’s song, Put the Lime in the coconut:
Put the LIME in the coconut, call your doctor, wake her up!
(with apologies to Harry Nilsson)
Brother bought a coconut, he bought it for a dime
His sister had another one, she paid it for a lime
She put the lime in the coconut, she drank them both up
She put the lime in the coconut, she spilled a little from her cup
She put the lime in the coconut, she had a rash when she woke up!
She put the lime in the coconut, she called her doctor, woke him up
And said, Doctor, ain’t there nothin’ I can seek?
I say, doctor, to treat these rashy streaks?
I say, doctor, ain’t there nothin’ I can seek?
I say, doctor, to lighten up my cheeks?