I think the history and description in the question is very brief,an also i would have asked for the pictures if you could upload as seeing a rash
is worthwhile in making a diagnosis in dermatology.
Now coming towards your question the medications which have been prescribed are H1 blockers and they usually prescribe them for Urticaria(hives
But i think you need a second opinion
from the dermatologist
because history of the urticaria is missing in your question and is more directing towards Scabies
which is an contagious infestation,so i think you need to be reviewed again to exclude it.
I hoe you would understand my point.
thanks very much,and all the best.