Four successive stages in the action of the alpha1-adrenergic blocker (α1-AB) are discussed in the article. When describing the pharmaceutical and pharmacokinetic stages, the features of absorption, bioavailability and distribution of three α1-AB are discussed: alfuzosin, tamsulosin and silodosin. From a practical point of view, it is important that the bioavailability of alfuzosin and tamsulosin will increase during transit through the gastrointestinal tract, which means that extended-release dosage form (Alfuprost MR) has advantages compared to conventional immediate-release tablets. Alfuzosin has the highest volume of distribution among α1-AB (2.5 l/ kg), which indicates its maximum prostatotropic index compared to other α1-AB. The clinical uroselectivity of α1-AB directly depends on their pharmacological profile, in accordance with the chemical structure and pharmacological properties. The clinical uroselectivity of alfuzosin is provided mainly by unique pharmacokinetic/functional properties (volume of distribution, prostatotropism), while tamsulosin and silodosin are dominated by the receptor/pharmacodynamic component. Controlled studies have shown that α1-AB reduce I-PSS by about 30-40% and increase Qmax by about 20-25%. Evaluation of the safety of α1-AB includes monitoring for side effects, including asthenia, dizziness, and (orthostatic) hypotension. According to a meta-analysis, the vasodilatory effect is most pronounced with doxazosin and terazosin, but is much less common and with comparable alfuzosin and tamsulosin. For personalized approach in choosing an α1-AB for the drug therapy of LUTS in BPH one should takes into
account, on the one hand, the individual characteristics of the patient (the presence of concomitant pathologies: arterial hypertension, coronary heart disease, diabetes mellitus), and on the other hand, the individual pharmacological profile of α1-AB, the risk of developing drug interactions. Based on the results of extensive clinical experience, including data from recent clinical trials, Alfuprost® MR (alfuzosin
10 mg in the form of extended-release tablets) demonstrated a pronounced clinical uroselectivity, high efficiency in the relief of LUTS and cardiovascular safety in comorbid patients, including those with cardiovascular diseases.

Keywords: drug dosage form, receptor selectivity, prostatotropic properties, LUTS, BPH, Silodosin, alfuzosin, tamsulosin, pharmacokinetics