Can the use of Contix and Nystatin to brush the tongue affect general blood tests, urine and cancer markers?

Nystatin does not affect the results of laboratory tests. Contix may interfere with tests that detect the presence of neuroendocrine tumors and chromogranin A (CgA), but you do not mention these tests in your question. If you have such tests ordered in the future, you should stop treatment with Contix at least 5 days before measuring the CgA concentration. If, after the initial measurement, CgA or gastrin values are still outside the reference range, the measurements should be repeated 14 days after discontinuation of treatment with proton pump inhibitors. I enclose a detailed description of the preparation you are asking about: https://www.gdziepolek.pl/produkty/19693/contix-tabletki/ulotka/112213 I enclose additional information that may be helpful: https://www.gdziepolek.pl/artykuly/jak-przygotowac-sie-do-badania-krwi https://www.gdziepolek.pl/artykuly/jak-przygotowac-sie-do-badania-moczu