I have a prescription toothpaste and a prescription cream which both exceed the magic 3.4 ounces and my SOP is to bring the cardboard boxes* that they come in as that has the prescription label containing all the pertinent info (my name, scrip info etc) and I've never had any issues both domestically and international
*I simply flatten the box and place it in a separate freedom baggie with the toothpaste and cream tubes