The purpose of this study is to evaluate the efficacy of the combination of Methenamine + Methylthioninium chloride compared to phenazopyridine (comparator product) in the symptomatic relief of dysuria.

• Single blind, randomized, prospective study.
• Length of experience: 03 days to 07 days.
• 03 visits (days 1, 4 and 7).
• Evaluation of the efficacy and safety of the medication.
• Shall be assessed for adverse events.

Inclusion Criteria:

• Patients who agree to participate by agreeing to the terms proposed in the Clinical trial;
• Patients aged over 18 years of any ethnicity;
• Presence of dysuria with marking greater than or equal to 5 measured points on the categorical scale pre-treatment for pain symptom;

Exclusion Criteria:

• Patients who are febrile (axillary T º: ≥ 38 ° C), with back pain or lumbar;
• Patients with complicated clinical presentation of urinary tract infection;
• Patients with a history of allergy or intolerance to any known or suspected one of the ingredients of the product under investigation;
• Patients who are pregnant or during lactation, or childbearing potential and are not making use of effective contraception;
• Patients presenting with renal disease or severe liver disease, according to medical history and / or laboratory;
• Patients presenting with severe systemic disease according to the known medical history;
• Patients who received antibiotic treatment, anthelmintic within 7 days prior to study entry;
• Patients unable to understand the guidelines specified in this protocol or can not attend all study visits or unable to complete the log;
• Pregnancy or risk of pregnancy and lactating patients;
• Any finding of clinical observation (history and physical examination) that is interpreted by the physician investigator as a risk to the patient's participation in the study.