The methodology is based on the detection and quantification of the immunogenic gluten peptides (GIP) in human samples (stool or urine) that through A1 or G12. They are highly specific monoclonal antibodies that recognize these epitopes peptidos19. This methodology is applied in sandwich ELISA techniques and a lateral flow chromatography. According to information published there is a correlation between ingested peptides and excreted in the feces that remain undigested. Fecal, GIP can be detected up to four days after being ingested and begins to be detectable at 2 days after ingesta16.