One has to touch poison ivy (or something that has urishiol on it, like a pet, shoe, clothing, tool) to get poison ivy. If you know, for sure, you have not touched poison ivy, or touched something that touched poison ivy, you can know it's something else giving you a rash. I was shocked to find how many people are out there, investigating a mystery rash, usually from the same angle of "I know I didn't touch poison ivy but have the rash," yet there's very little info to help. Plants that definitely did not used to bother me before, propagated them many times, and definitely got sap on my skin, are now dangerous to me.

Nobody knows why sensitivity to previously harmless exposure to certain plants can suddenly result in dermatitis. Sensitivity to urishiol, and the plants below can be transient.

The details of the 2-year investigation might bore you, but in a nutshell, I'm suddenly susceptible to getting this rash from Aroids, heart-leaf Philodendron vines in particular. Test exposure confirms, that's (one of the plants) giving me a rash. A long lasting rash that's itchy enough to ruin sleep, scratch like a dog in public, be the foremost thought on your mind for about 8-10 days, and I don't know if some minor scarring is from too much scratching or would have happened anyway at what seemed to be the most exposed spots. Syngonium is another one. Rudimentary investigation leads to the word alkaloid. It's thought these plants have irritating alkaloids.

Interesting because Tradescantia zebrina and Callisia repens are also giving me a rash, and also contain alkaloids, though they are in the Commelina family. I'm suspicious of T. pallida also, but done experimenting. I've scratched enough.

Now also giving me a rash is anything with latex...
such as Ficus (fig, rubber tree)
Euphorbia (yard spurges and many potted succulents)
Plumeria (Frangipani, the Hawaiian lei flowers)
Asclepias (milkweeds)
Ipomoea (morning glory, moonflower vine, sweet potato vine)
Sonchus (dandelion, sowthistle.)
What other plants contain latex sap?

Have you ever gotten a rash from a house plant? From gardening outside but you KNOW there's no poison ivy? Do you know anything (relative to contact dermatitis) about these alkaloids? Sources of more info? I don't understand much about the science, though I would read more info gladly.

I wanted to both raise awareness for those who would just prefer to avoid the sap of these plants instead of finding out if they can get a rash, and to help those investigating 'mystery poison ivy.' I would consider these plants at the top of a list to keep away from kids (plants to keep away from particular pets are well documented, and not an issue I have.) I'm also left with some questions, as asked here.

I'm not giving up any of these plants but definitely handling with caution when sap is exposed. By that I mean I intend to make sure I don't get any sap on my skin. I don't unknowingly trim or cut plants, so this shouldn't be too difficult, but might involve rubber gloves. As far as I can tell, once the sap dries, it's harmless. Once the site where a cut was made has healed over, it's harmless. Confirmation/disagreement? I'm leery about pulling off dead leaves, from T. zebrina in particular. They just don't want to let go. I know I'm compulsive about doing this, so if I end up scratching again and this was the only possible exposure, will report here. Going to try to train myself to cut them with a little scissors though. I have this stuff in many, many pots, as filler.

Couldn't find any reference to anyone getting dermatitis from casually touching the leaves of any 'house plants,' with the possible exception of some of the Ficus, F. benjamina in particular. No proof in the encountered anecdotes about 100% certainty the exposure was only casual. It seems a leaf could be bent enough to break open and expose sap, but 'fold' back to a normal looking position, making the rash seem to come from casual contact when there was sap involved, IDK. Am I willing to experiment - more? Nooooo way!

Edited to add: Also wanted to encourage anyone who gets a rash from a house plant to put that info in the plant database. Knowing beforehand can avoid a lot of misery.

I know how you feel. I am very fair-skinned and often have rashes that I don't have a clue how or where they originated. I'm trying to make better mental notes. I know the sap of Euphorbias can cause rashes, sometimes very nasty ones. That includes a lot of plants, both forb and succulent, such as Crown of Thorns.

Purple when I was trimming the leaves back from my pregnant onion plant, it gave me the worst rash I had ever experience. My skin literally felt like it was on fire. I washed my hands and arms several times, put medicated powder on, took some Benadryl and all of that didn't help. I had to wait 3 or 4 days for the rash to finally go away. Now every time I see that plant, I'm more cautious around it lol

Excellent inputs, TY!

I'm guessing your pregnant onion was Albuca bracteata {formerly known as Ornithogalum caudatum}? I did a quick search and found other anecdotes of this giving people a rash, Fo' Sho'!!

FWIW, I'm not fair at all, quite the opposite, more Mediterranean. Until the past few years, none of the plants I mentioned gave me a rash except poison ivy. So glad I finally realized it was 'my old buddies' that had turned on me. Not that I'm happy about that, but I know how to stop getting itchy rashes.

Some years ago, I got a rash from my ankles to my kneecaps. I had previously been cleaning out our farm pond and initially thought that was the culprit. When I finally sought help from a dermatologist, he diagnosed my rash as phyto-photo-dermatitis and thought it was more likely I had been in contact with a weed in the umbelliferae family. He told me it was the combination of sunshine activating the plant at a certain stage of its life causing it to release toxins that I was sensitive to. That rash lasted at least 2 months and was quite unsightly. I've never had a repeat experience, so it must have just been some random collision of all three factors.

You're right Purple. I didn't know the name changed from Ornithogalum to Albuca. I learned something new.

Tiffany and all else here.
This may not work for you but it saved my life more than once. I used to get poison ivy and really bad at that. Eyes closed, face swellon and overall very painful. By totally accident, while showing, I started to use ''Head and Sholders'. The regular stuff. No fancy kind. Next thing I noticed, hands and face are clear. Next body wash with it. And never had any rashes again. Also, I was moving some Euphorbia spurge plant. A hardy kind. It's sap is many times stronger than my Euphorbia house plants. Just washed my hands and a little latter rubbed my eye. All hell fire broke out. In the shower with my Head n Sholders and it did the trick. All was well.
In extream cases, Wash in warm water with the Head n Sholders then rinse cold water then repeat. In an hour may have to do it again. Also good to use as a lotion to just dap on a section to wash later. I have reported this before so I hope some one remembers this.
Stush

For those that might grow the herb Rue (Ruta graveolins) or have it grow wild in their area, it is another plant that can trigger photo dermatitis.

I'm fortunate not to have reactions to any of the above mentioned plants but the caution is always on my mind. I wear gloves and wash up when done. Using Head & Shoulders is also good advice I will remember. Thanks.

Thanks Stush! It is good to have a remedy ready if one fails to avoid the sap, and for those who develop a sensitivity to things that didn't bother them before. I've gotten really weird about it, stopping to wash my hands several times while packing up a box for trade last week. (Then went camping and am scratching a ton of bug bites as we speak - seems I'm just destined to be scratching, one way or another, most of the things I enjoy cause itching!)

Kristi, I think that's why they call it rue? Its' reputation keeps me away, no doubt. There's a whole 'nother slew of plants outside that can make me itchy, even before my skin 'turned sensitive.' Juniper and nightshade vine come to mind first, though luckily the itching and (longevity of it) from those is not in the same league as a latex or Philodendron rash - personally. Others' experiences may vary.

It sounds like it may be best to avoid most contact with plants in the heat of the day (as if the heat itself wasn't enough of a factor.)

I just got a rash from cutting back Euphoria 'Fens Ruby' - I didn't notice the white sap until I was almost done with a fairly large clump. Fortunately, I went to an herb fair the next day and was able to try out a couple different salves. Found one that has provided good relief. Julia's Good Medicine, Wonderful First Aid Herbal Salve. Has all sorts of oils, herbs, and essential oils in it. Feels and smells good.

I wanted to add. 'Head n Sholders' is not just an old wives tell. Like so many other soaps and oatmeal or even bathing in clorox. Which some times works but at what cost.
There is an anti-itch and then the lanolin lotion. A one two punch. There may be other anti-itch medications that may work as well. I noticed that generic lotions don't seem to be as effective as orginal Head n Sholders. I wish some one would have told me about this 10 years ago.
Stush

I gave that tip to my sister who just had a run-in with poison ivy. My husband has a bad case of sand flea bites and H&S only made it worse for him, so not particularly effective against insect bites (for him anyway).

Deb,
So sorry to hear that. I guess I am lucky to not have heard of 'Sand Fleas'. I have used the H&S on my dog and it seems to help her out. I wonder if something like Avon's 'Skin so Soft' could help out. It's oils could smother the fleas and repel them. Used to use on our dogs until they came out with K-9 advantix. I have heard even used dryer sheets kept around the neck repels gnats. I hope your sister had better luck.
Stush

Deb, are they these?:
http://entnemdept.ufl.edu/crea...

IDK if they're exactly the same where you are or not, but those things got me last Saturday along FL gulf coast and I'm still scratching. I only live about 90 minutes from the beach, so visit often, but have never run into a swarm like that before, or been bit by anything on the beach besides a crab. It was our 6th time camping in that state park and I hope they are gone when we go again @ the end of this month. And speaking of dermatitis, the park is full of poison ivy. We just don't touch it!

That could be them, they are tiny translucent bugs that hop on you at a salt water beach. Locally, we call them sand fleas, which may or may not be their proper name. Whatever they are, my husband is still itching like crazy after 2 weeks.

That sounds like the same kind of critter, if not the exact same species - 2 diff oceans. Yes, FL panhandle beaches are definitely salt. Sand flea is the first name I got trying to figure out what they were when we got home. Sandfly is also a common, common name. I can't say here what I call them, it's not rated G!!

TWO weeks?! Puts mosquito bites in perspective, huh?

Tuesday I was cutting and packing slips of heart-leaf Philo vine to share and apparently brushed against a cut vine with my arm, getting sap on my arm. I was trying not to do that, and washed about 5 times during the process of taking the cuttings and packing them, but didn't think I'd touched anything higher than midway to my elbow. Thursday, this spot turned red and itchy. Raised blisters showed up over the weekend.

Might as well share a pic to help make this suffering educational. This is as itchy or more itchy than poison ivy. Since it's been a couple decades since I had PI, it's hard to compare.

Philodendron rash:

Forgot to paste the list I'm always working on...

The formatting gets lost, but it's a 3-column spreadsheet:
Botanical name, common name if known, detail about toxicity.
If anyone wants a copy of the spreadsheet, I'd be happy to email it to you, send me a PM.

Acalypha hispida Chenille Plant causes skin and gastrointestinal inflammation
Adenium
Agave Agave oxalates
Aloe nobilis Gold Toothed Aloe possible dermatitis
Amaryllis Amaryllis alkaloid
Amsonia
Asclepias milkweeds, butterfly weeds latex sap
Asparagus densiflorous Sprengeri Sprengeri Fern possible dermatitis
Asparagus setaceus plumosus Asparagus Fern dermatitis
Brossimum
Caladium Caladium oxalates
Calla Calla oxalates
Carica
Carissa latex
Castilla latex
Catharanthus latex
Celandine latex
Ceropegia latex
Chrysanthemum Chrysanthemum may give dermatitis
Codiaeum variegatum Croton many species contain croton oil, a strong purgative which causes gastroenteritis
Colocasia Elephant ear oxalates
Convallaria majalis Lily-of-the-Valley glycosides
Crinum Crinum alkaloid
Cyclamen persicum Cyclamen a case of poisoning was reported in 1798
Cyperus alternifolius Umbrella Plant toxic
Dieffenbachia Seguine Dumbcane oxalates
Epipremnum Pothos oxalates
Euphorbia Crown of Thorns, Poinsettia toxic, latex sap
Euphorbia latex
Ficus Creeping Fig, weeping fig, rubber tree possible contact dermatitis via casual contact and/or latex sap
Fockea latex
Glechoma hederacea Creeping Charlie, Ground Ivy toxic
Hedera helix English Ivy toxic
Helleborus niger Christmas Rose glycosides
Hoodia latex
Hoya latex
Huemanthus Blood lily alkaloid
Huernia latex
Hydrangea Hydrangea cyanogenetic glycoside
Lactuca latex
Lantana Lantana berries of some species toxic
Maclura latex
Mammillaria latex
Mandevilla latex
Manilkara latex
Mimosa pudica Sensitive Plant possibly toxic
Monstera deliciosa Split Leaf Philodendron oxalates
Morus latex
Narcissus Narcissus alkaloid lycorin
Nerine Nerine alkaloid
Nerium Oleander Oleander glycosides
Pachypodium latex
Papaver latex
Parthenocissus quinquefolia Boston Ivy oxalates
Persea americana Avocado possibly toxic
Philodendron hastatum various cultivars oxalates
Philodendron scandens & various synonyms Heartleaf Philodendron oxalates
Plumeria/Frangipani latex
Poinciana gilliesii Bird-of-Paradise toxic
Polygonatum Jack-in-the-pulpit oxalates
Primula Primrose possible dermatitis
Rheum rhaponticum Rhubarb oxalates
Rhododendron occidentale Azalea toxic
Rhubarb Rhubarb oxalates
Sansevieria Snake plant, mother-in-law's tongue oxalates
Scindapsis Devil's ivy, Pothos oxalates
Solanum Bittersweet nightshade, Jerusalem Cherry solanine
Sonchus latex
Spathiphyllum peace lily oxalates
Stapelia latex
Stephanotis latex
Syngonium podophyllum Arrowhead Plant oxalates
Tabernaemontana latex
Taraxacum latex
Toxicodendron Poison ivy, oak, sumac urishiol
Tradescantia Wandering Jew, Purple Heart, Rhoeo spathacea oxalates
Wrightia latex

Be very, very careful. Rashes are not something to mess with, especially if they are "raised" as in the photo. Hives can get out of control, and you can go in anaphylatic (sp) shock. This can result in death within an hour. Your throat can swell so much that your breathing is cut off, and you can die that way as well. The body is not recognizing what you have been exposed to, and so it over-reacts, trying to protect itself, Its your immune system in overdrive, basically. I've had allergies to all kinds of things that has gotten worse with age. I have over a dozen food allergies, and things I touch during the day. Most are never identified. Its so bad that the doctor has put me on Atarax three times a day, and my troubles are mostly gone. If you're that bad, you should consider it too. It got so bad that I was having panic attacks, afraid I'd get the lip, tongue and throat swelling, and die before I could get help. Its turned into a phobia as a result.

I don't want to scare anybody, but this should not be taken lightly. For some people, the more you're exposed to the world, the more allergies you seem to acquire. But for many, antihistamines, such as Atarax, can help tremendously. I wish I'd started taking it many years ago! Before I was taking it, I'd get a hive or two several times a month that would itch like the dickens for days. Atarax can be a little sedating to some people, but that's fine for me, because I'm high strung and have anxiety. When you ask an expert, their answer is always the same--AVOID the trigger. So if certain plants set you off, it could get much worse in time, and personally, it would not be worth it to me to take that kind of risk.

Seaecho, that sounds quite frustrating! TY for sharing your story.

I can only hope my assumption that this rash is topical, from getting plant sap on my skin, is correct. A further reaction could be possible. I've only gotten this rash 2-3 days after cutting into certain plants.

I would have to give up most of my house plants to eliminate this threat. As far as I know, I'm only at risk when I cut into them, exposing the sap inside, and only then if I get the sap on my skin and fail to wash it off within a few minutes. *Hopefully...!*