PurposeTo evaluate and investigate the effects of α1‐adrenoceptor antagonist tamsulosin hydrochloride on anterior and posterior segment findings using Sirius Scheimpflug/Placido photography‐based topography system and enhanced depth imaging spectral‐domain optical coherence tomography (EDI‐OCT).MethodsThis prospective study was performed with newly diagnosed benign prostatic hyperplasia, 25 eyes of 25 patients, initiated tamsulosin hydrochloride, were evaluated in this study. Anterior segment and posterior segment findings were noted at baseline, 1st and 3rd month. Results were compared statistically.ResultsThe mean subfoveal choroidal thickness 269.65 μm, and the mean 3 mm nasal and temporal thicknesses were 262.85 and 264.70 μm respectively at baseline and they were 270.15 μm, 263.15 μm and 264.95 μm at 1st month and they were 270.75 μm, 264.05 μm and 265.90 μm at 3rd month (p > 0.05, at all study visits). The mean schirmer test values were 13.10–12.35 and 10.95 mm, respectively (p < 0.001). The mean scotopic, mesopic and photopic pupil diameter values were 6.60 mm, 5.11 mm and 3.48 mm at baseline, and they were 6.58 mm, 5.10 mm and 3.44 mm at 1st month and 6.51 mm, 5.06 mm and 3.45 mm at 3rd month (p > 0.05).ConclusionsSignificant increase of subfoveal choroidal thickness was not detected. But tamsulosin effected the mean nasal and temporal choroidal thicknesses during study period. There were no significant decreases of scothopic, mesopic and photopic pupil diameter sizes in pupillography, it can be considered that tamsulosin doesn't effect pupil size.