Comparison of tamsulosin with alfuzosin in the treatment of patients with lower urinary tract symptoms suggestive of bladder outlet obstruction (symptomatic benign prostatic hyperplasia). The European Tamsulosin Study Group.

Objective: To compare the efficacy and tolerability of the alpha 1 A-subtype selective drug tamsulosin with the nonsubtype-selective agent alfuzosin in the treatment of patients with lower urinary tract symptoms (LUTS) suggestive of bladder outlet obstruction (BOO), often termed symptomatic benign prostatic hyperplasia (BPH).

Patients And Methods: The study comprised 256 patients with benign prostatic enlargement and LUTS suggestive of BOO (symptomatic BPH) who received tamsulosin 0.4 mg once daily or alfuzosin 2.5 mg three times daily during 12 weeks of treatment. The response was assessed by measurements of maximum urinary flow rate (Qmax), a symptom score (Boyarsky) and blood pressure at regular intervals.

Results: Tamsulosin and alfuzosin produced comparable improvements in Qmax and total Boyarsky symptom score. Both treatments were well tolerated with respect to adverse events. Tamsulosin had no statistically significant effect on blood pressure compared with baseline but alfuzosin induced a significant reduction in both standing and supine blood pressure, compared with baseline (P < 0.05).

Conclusion: Tamsulosin is the first adrenoceptor antagonist that is selective for the alpha 1 A-subtype; this specificity may explain its lack of effect on blood pressure compared with alfuzosin, an agent that is not receptor subtype specific. Moreover, this finding may partly explain why tamsulosin, in contrast to other currently available alpha 1-adrenoceptor antagonists, can be administered without dose titration. Another advantage compared with alfuzosin (and prazosin) is the once-daily dosing regimen of tamsulosin.