how to stop my LO scratching?!

My step daughter has eczema, unfortunately she gets it from my partner! Like him she scratches and scratches and just won't stop! We try covering her in emulsifier ointment and we even try putting something cold on the places she scratching but she just won't stop. She screams if we try to take her hands away, and I know how fustrating it must feel because I use to do the same when I was her age (I also have eczema) were potty training her at the moment, so the scratching is getting worse as she's walking  around with no bottoms on! Any advice on trying to get her to stop?! I'm sick of asking her to stop constantly and covering her in cream! We bathe her every night too to try and ease the pain. She 2 and 8 months! Any advice is welcome