A method for treating a disease selected from gastrointestinal motility disorder, irritable bowel syndrome, chronic constipation, chronic idiopathic constipation, chronic constipation occurring in cystic fibrosis, opioid-induced constipation, chronic intestinal pseudo-obstruction, colonic pseudo-obstruction, ulcerative colitis, inflammatory bowel disease, gastrointestinal tract disorder is associated with chronic kidney disease (stage 4 or 5), constipation induced by calcium supplement, constipation associated with the use of a therapeutic agent, constipation associated with a neuropathic disorder, post-surgical constipation, idiopathic constipation, constipation associated with neuropathic, metabolic or an endocrine disorder, constipation due the use of drugs selected from analgesics, antihypertensive, anticonvulsants, antidepressants, antispasmodics and antipsychotics, gastric ulcers, infectious diarrhea, leaky gut syndrome, cystic fibrosis gastrointestinal disease, microscopic colitis, necrotizing enterocolitis, atopy, food allergy, acute inflammation, chronic inflammation, obesity-induced metabolic diseases, kidney disease, chronic kidney disease, diabetic kidney disease, heart disease, heart failure, congestive heart failure, hypertension, essential hypertension, primary hypertension, salt-sensitive hypertension, liver disease, cirrhosis, nonalcoholic steatohepatitis, nonalcoholic fatty liver disease, steatosis, primary sclerosing cholangitis, primary biliary cholangitis, portal hypertension, Type 1 diabetes, celiac disease, multiple sclerosis, ankylosing spondylitis, rheumatoid arthritis, lupus, alopecia areata, polymyalgia rheumatica, multiple sclerosis, fibromyalgia, chronic fatigue syndrome, Sjogren's syndrome, vitiligo, thyroiditis, vasculitis, Crohn's disease, ulcerative colitis, urticaria, Raynaud's syndrome, schizophrenia, autism spectrum disorders, multiple sclerosis, hepatic encephalopathy, small intestinal bacterial overgrowth, secondary hyperparathyroidism, celiac disease, hyperphosphatemia, vascular calcification, elevated FGF-23 levels, cardiac hypertrophy and chronic alcoholism treating in a human, comprising administering to the human a compound that inhibits antiport of sodium ions and hydrogen ions mediated by NHE-3.