If your Doctor or Health Care Provider prescribes the tests, how long do I have to wait after the end of ProLon® 5-day? 29 June 2022 15:00 To have reliable analyses, it is necessary to wait at least 15-20 days after you finish this Fasting Mimicking Programme. Related articles How many times can I repeat ProLon® 5-day? Can I do ProLon® 5-day if during menstrual cycle? Do ProLon® 5-day Menus 1 and 2 contain nickel? Do I lose weight?