The primary objective is to determine the compared clinical efficacy of Lactase Eurofarma (test drug), showing non-inferiority to Lactaid® (comparative drug) in the supportive treatment of lactose intolerance and to assess the safety and tolerance of Lactase Eurofarma (test drug) in the supportive treatment of lactose intolerance.

Inclusion Criteria:

• To have participated in the single-dose clinical study (EF099) previously performed, with the clinical response being considered as satisfactory by the investigator
• The patient should be a male or female, aged between 18 and 60 years old
• Have a medical history consistent with lactose intolerance, confirmed by the test of hydrogen in the expired air
• The female patients should agree to use birth control methods during the study participation
• To be able to meet the study instructions and all the visits required
• To give a free consent to participate in the study and sign the informed consent form (ICF).

Exclusion Criteria:

• Smoking
• Secondary hypolactasia
• Gastrointestinal inflammatories diseases - present diverticular disease, diabetic gastropathy or neoplasias
• Colonoscopy or colon cleaning procedure 4 weeks before the start of study
• Latrogenic: unnoticed intake of laxatives in over-the-counter drugs or alternative medicine, intake of cereal bran or probiotics
• Diagnosis of HIV, immunodepression of any origin, or cancer under treatment.
• 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),
• 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
• Incapacity to understand and complete the study questionnaires, including the questions that require the use of the Visual Analogue Scale and ICF
• Pregnancy or lactation
• Use of alcohol, exceeding 3 doses daily
• Participation in another clinical study on the last 12 months
• 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).