Hi Northumberland,
My husband’s experience of all over rash was with Thalidomide in the first treatment cycle. It started after about 5 weeks, and spread quite quickly over the whole body. After a pause, the drugs regime was changed to Lenalidomide (which we were told is related to Thalidomide), and he tolerated that without any problem at all. It seems that different people react to different drugs, and maybe you need to talk with your experts about trying an alternative.
Hope this helps.
Lili B x