Beware of hairy yellow caterpillars with black spikes. They are American dagger moths that have have toxic properties when hairs are touched. One slight brush sent me to the ER with significant hives, elevated blood pressure, facial flushing, and chills.
I did some online research and learned that pets who innocently consume the caterpillars can also become ill enough to seek a vet's care. I am still afflicted with hives after three days and am dosing with Benedryl. One helpful hint is applying ice directly on hives and it has helped when topical cortisone and oral medications have fallen short relieving the itching.
You can Google search a photo and info about American Dagger moth and other toxic hairy caterpillars all over the US. I also found many other home remedies for hives.
By Kathy from Western PA
My son came into contact with this caterpillar and has hives/rash going from his stomach to his one knee and had to go to the hospital. Benadryl and a cream is what he has been given. Hope this helps anyone.
I had one right next to my front door today. Glad I told the kids not to touch it. The black spikes through me of. And it was yellow. Most creatures with those type of colors use that as a way to get prey or defense.
I think they only cause hives/rash if you are allergic to them. As you would theoretically only know if you are allergic by handling them, it is probably better to avoid them. We have them all over the place near the Pittsburgh area, and I know dozens of people who have handled them with no issues, kids and adults. I only know of one person who experienced very minor redness and irritation after touching one for a long period of time (several minutes).
Glad to hear you found remedies for your hives!!
I found one of these caterpillars on our back porch yesterday. It had the long fuzzy yellow hair and black spikes. I also noticed it had a black shiny head with two tiny white dots which resembled eyes although I am not sure if that is actually what they were. I did not touch it but took several pictures. Years ago my then two year old little girl played with a large fuzzy light yellow caterpillar for quite a while. Then she came to me saying her hands itched. Her little palms and fingers were bright red and so swollen they were actually bent backwards. My doctor had me give her benadryl. When she was about eight years old, she played with a smaller black and white one and had the same reaction. When she was ten I bought her a pair of "fur-lined" boots that were made in Korea. Her feet had the same reaction. It made me wonder if they make artificial fur over there using caterpillar hair?