Evaluation of GIMate Handheld Hydrogen Breath Monitor for Diagnosis of Lactose Malabsorption

Inclusion Criteria: 1. Healthy male or non-pregnant female between 18 and 55 years of age (inclusive) 2. Able and willing to provide written consent and follow instructions to complete required study procedures (including dietary restriction) and questionnaires. 3. Self-reported or suspected history of lactose malabsorption or lactose intolerance Exclusion Criteria: Exclusion criteria: 1. History of prior gastrointestinal surgery 2. Self-reported history of any chronic gastrointestinal disease (examples include gastroesophageal reflux disease, celiac disease, Crohn's disease, ulcerative colitis, pancreatitis) 3. Self-reported history of endocrine or metabolic disease that may impact gastrointestinal or colonic function (examples include hyper/hypothyroidism, diabetes, etc) 4. Clinically significant cardiovascular, respiratory, renal, hepatic, hematologic, neurologic or psychiatric disease for which chronic therapy (prescription or non- prescription is required) 5. Self-reported history of allergic reaction to any drug or drug component 6. Antibiotic use within 28 days of lactose malabsorption test 7. Use of non-antibiotic prescription or OTC products (dietary or digestive supplements and laxatives) within 14 days of testing. 8. Self-reported use of nicotine-containing products or chronic secondhand smoke exposure within 14 days of testing. 9. Any other condition which in the Investigator's opinion may adversely affect the participant's ability to complete the study or its measures or which may pose significant risk to the participant. 10. Consumption of food after midnight on day of testing (within 12 hours) of testing or consumption of non-water beverage after midnight (or less than 8 hours) prior to testing.