Background. Functional dyspepsia is characterized by symptoms that apparently originate in the stomach without detectable cause by conventional diagnosis test. The pathophysiology of functional dyspepsia is not known, but a number of data indicate that dyspeptic patients have increased sensitivity of the digestive system, so that physiological stimuli may induce their symptoms. Some patients with functional dyspepsia have also functional constipation and the investigators hypothesize that in them constipation triggers or facilitates dyspeptic symptoms, and consequently, correction of constipation relieves dyspeptic symptoms.