It will be an open-label, randomized, laboratory-blind, crossover study with 02 treatments, 02 sequences, and 02 periods, in which the volunteers receive, in each period, the test formulation or the reference formulation, under fed conditions.

It will be an open-label, randomized, laboratory-blind, crossover study with 02 treatments, 02 sequences, and 02 periods, in which the volunteers receive, in each period, the test formulation or the reference formulation, under fed conditions.

The treatment's sequence attributed to each volunteer on the study period is determined by a randomization list, which is generated by PROC PLAN from SAS version 9.1.3 system.

The formulations will be administered as a single oral dose followed by blood collections between, at least, 3 to 5 half-lives. The treatment's periods may obey a minimum interval of 7 half lives between them (period for drug's whole elimination by the organism).

EXCLUSION CRITERIA:

• The volunteer has a known hypersensitivity to the study drug (tamsulosin hydrochloride) or to compounds chemically related;
• History or presence of hepatic or gastrointestinal illnesses, or other condition that interferes over the drug's absorption, distribution, excretion or metabolism;
• History of hepatic, renal, pulmonary, gastrointestinal, epileptic, hematologic or psychiatric illness; hypo or hypertension of any etiologic that needs pharmacologic treatment; has history or had myocardial infarction, angina and/or heart insufficiency;
• Non-recommended electrocardiographic findings, according investigator criteria;
• The results of the laboratory exams are out of the values considered as normal according this protocol's rules, unless that they are considered as clinically irrelevant by the investigator;
• Volunteer is a smoker;
• The volunteer ingests more than 5 cups of coffee or tea a day;
• Has history of alcohol or drugs abuse;
• History of serious adverse reactions or hypersensitivity to any drug;
• Use of any regular drug within the 02 weeks that preceded study's initiation or treatment within the 03 previous months, that preceded study's initiation, with any drug that presents toxic, or volunteer consumed inductive drugs and/or enzymatic inhibitor (CYP450 - hepatic), within the 04 weeks that preceded the study's initiation;
• Volunteer was hospitalized for any reason within the 08 weeks of the beginning of the study's first period of treatment and the post study assessment date;
• Participation in any experimental study or ingestion of any experimental drug within the 06 previous months;
• Volunteer consumed alcohol in 48 hours prior to the admission to the study or consumed foods or beverages that contain grapefruit until 07 days previous to each study period.

INCLUSION CRITERIA:

• Male;
• Age between 18 and 50 years;
• Body mass index ≥ 19 and ≤28,5;
• Good health conditions or without significant illness, by judgment of a legally qualified professional, according the rules defined in Protocol, and according the following evaluations: clinical history, pressure and pulse measures, physical and psychological exam, ECG, and additional laboratory exams;
• Capable to understand the study's nature and aim, including the risks and adverse effects and with intention to cooperate with the researcher and to act in compliance with the requirements of the whole assay; this will be confirmed by the Informed Consent's signature.