breastfeeding and excema

Hi. My 4 month old daughter suffers terribly with excema. It seemed to start after she had her first immunisations although I have been told this could be a coincidence. I havent let her have her third set of immunisations as Im afraid for her. Her scalp is the worst. Cradle cap developed into excema and she scratches at her poor head all the time often leavibg it weeping and bleeding if left to her devices or during the night. I have used fucidin cream with great success but this cant be used for more than a week and then it comes right back. Her torso is red, angry and raised with some broken patches. Tops of arms are quite bad and her legs are just dry. Her scalp crusts over and looks awful. Her nappy area is completely clear. She has been given antibiotics fo 'infected excema' but this didnt do anything and I never want to use this again. It caused her more stress and upset including nappy rash. She is solely breast fed and I am currently trying to cut out cows milk products and substituting with goats milk myself. I crave a lot of sugary products and I do worry that this is causing her problems. Other than that I am having a healthy diet and avoid caffeine and alcohol.
Please please can someone help.
Mrs Bee with Baby Lu.