Baby facial outbreak

my friend's baby is about 4 mo. old.  she has been breast feeding and started supplementing with milk-base formula.  Baby just recieved chicken pox vaccine shot about a week ago. about four days ago she broke out around the mouth on nose and all is like boils, red, pus-filled then scaly and peeling.  Dr. prescribed an anti-viral for herpes/fever blisters but (both parents are healthy) baby is now breaking out on her legs and trunk.  I noticed small pin-point size dots starting on her two weeks ago when I fed her her first formula.  My babies used to break out mildly like this when I fed them soy or milk formula until I switched to lactose-free.  Could this be an allergy due to the formula, or is there something the Dr. could have missed?  It seems to be getting worse and not better.

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From my experience your concerns and suspensions are justified and well informed.  The doctor probably wanted to address a possible worse case scenario first, but the wrong formula frequently causes the problems you have mentioned if the peeling is not too deep into the skin.