Can I switch the boxes’ order? 22 February 2022 07:13 No, you should not switch the boxes' order, as each day of ProLon has a precise caloric and nutritional balance. Related articles Can I replace a food or ingredient with another? Is tea, coffee or infusion allowed during ProLon? Can I chew gum during ProLon®? Can I do ProLon® 5-day if during menstrual cycle? Can I extend the fast?