You know, my daughter is 11 and has had the same thing recently. She goes to Jenkins Middle, don't know if this is something to that. But, I found that when she put cream on , it got so much worse it seemed. I have been doing as what I do with my daughter who used to have eczema... not putting normal moisturizer and just using plain old olive oil on the skin when she bathes and giving benedryl. The cream I had tried to give her made it so much worse. I think it's an allergy related thing with my daughter, and then the cream that has cetyl alcohol or benzo alcohol or anything with the word alcohol in it made it flare up even worse! She has never been allergic to body cream in the past, so I know whatever it is that is making her hands turn red, she just can't use regular lotion to moisturize the area or it will make matters a 100 times worse.
I can use regular cream, it doesn't bother me, even though I do have allergies and a history of asthma. but I don't know why the cream does make it worse for her.
But she's better now using the olive oil- that with the benedryl and putting drops of organic lavender essential oil on it and a very little bit of peppermint oil to take the pain away, and help with the itch of it, but the peppermint oil is very diluted with the olive oil.
It was weird because we too didn't change anything different in the house. And this started as soon as 2 weeks ago for her I think. She's fine now, but I would take your daughter to the doctor, because depending on how bad the reaction is, she may need steriods to help with the rash, depending on what it is, and it would be terrible if it got worse.
Poor girl, my daughter only had it on the back of her hands, not the palms and a little on the cheeks, but the thighs, that sounds awful and miserable, I really feel for your daughter. I hope she gets better soon and that you will let us know how she is doing.
P.S. Last spring break I got a sunburn and when my skin was healing the itch was awful. At that time I tried everything, but Aveeno oatmeal is what helped to calm the itch and pain better than anything else.
I also wanted to note that the redness my daughter has was on the back of her hands, but the palms of her hands were fine and a little on her cheeks on her face. It was very strange locations, and in the past when my children have had allergic reactions internally it didn't always show up in a place where they touched something or came in contact with something that gave them an allergy.