Thanks for writing to the forum!
Well, itchy palms
with tiny white blisters could be eczema, fungal infection, dermatitis, contact allergy with allergens like soap, chemicals etc. If you itch between fingers too, there are chances that it is scabies. There are many OTC scabies lotions which you can apply and see. It could be viral in origin—as a part of hand foot and mouth disease.
Hope this helps. I think you should discuss these possibilities with a skin specialist.