The primary purpose of this exploratory study is to measure orocecal transit time using the SmartPill ambulant capsule technology and to compare this with the lactulose hydrogen breath test. Additionally, the ability of the SmartPill GI Monitoring System to discriminate between healthy human subjects and patients with small bowel bacterial overgrowth will be explored using analyses of both pH and pressure patterns within the stomach and small intestine. The study will be performed in both normal subjects and patients with and without small bowel bacterial overgrowth.