Interestingly the leaflet with the diffundox xl (Tamsulosin hydrochloride ) lists as
Not known (cannot be estimated from the available data)
'little or no semen ejaculated at sexual climax,cloudy urine following sexual climax'
Which seems to conflict with this:
'in controlled clinical trials, the percentage of patients treated with the α1A-selective α-blocker tamsulosin who reported abnormal ejaculation varied between 4% and 26%, depending on dose and study duration. In a long-term, open-label extension study, 30% of patients treated with tamsulosin reported abnormal ejaculation. In contrast, incidences of abnormal ejaculation related to the use of nonselective α-blockers, such as doxazosin, terazosin, or alfuzosin, generally were lower than 1.5%.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2812888/
For info