A Non-inferiority, Multicenter and Randomized, Single-Dose Study About a Treatment to Hypolactasia (LAILAI)

Inclusion Criteria: 1. The patient should be a male or female, aged between 18 and 60 years old; 2. Have a medical history consistent with lactose intolerance, confirmed by the test of hydrogen in the expired air; 3. The female patients should agree to use birth control methods during the study participation; 4. To be able to meet the study instructions and all the visits required; 5. To give a free consent to participate in the study and sign the informed consent form (ICF). Exclusion Criteria: 1. Smoking; 2. Secondary hypolactasia; 3. Gastrointestinal inflammatories diseases - present diverticular disease, diabetic gastropathy or neoplasias; 4. Colonoscopy or colon cleaning procedure 4 weeks before the start of study 5. Latrogenic: unnoticed intake of laxatives in over-the-counter drugs or alternative medicine, intake of cereal bran or probiotics; 6. Diagnosis of HIV, immunodepression of any origin, or cancer under treatment. 7. Diagnosis of other comorbidity that, at the investigator's discretion, may compromise the study participation (e.g., systemic infection during the study or use of antibiotics in the last 4 weeks, diabetes mellitus, uncontrolled hypertension or renal failure), 8. Hypersensitivity or previous laboratory or clinical adverse event related to the use of lactase or any of the components of the formulations used in the study; 9. Incapacity to understand and complete the study questionnaires, including the questions that require the use of the Visual Analogue Scale and ICF; 10. Pregnancy or lactation; 11. Use of alcohol, exceeding 3 doses daily; 12. Participation in another clinical study on the last 12 months; 13. Patient having some chronic pulmonary disease that, in the investigator's opinion, may harm or interfere with the expired hydrogen test (e.g., cystic fibrosis).