This early phase I trial studies the guanylyl cyclase C (GCC) agonist effect on cGMP signal
in duodenal tissue. Plecanatide and linaclotide are drugs approved by the Food and Drug
Administration for the treatment of conditions related to constipation. This trial aims to
see the effects of taking either one of two drugs, plecanatide or linaclotide, or no drug, on
a certain chemical found in the tissue collected from small intestine and how they compare.