Tamsulosin use in benign prostatic hyperplasia and risks of Parkinson's disease, Alzheimer's disease and mortality: An observational cohort study of elderly Medicare enrollees.

PURPOSE: To study the effects of benign prostatic hyperplasia treatments, namely: alpha-adrenergic receptor blockers, 5-alpha-reductase inhibitors and phosphodiesterase-5 inhibitors on the risk of Parkinson's disease, Alzheimer's disease and mortality. MATERIALS AND METHODS: All male Medicare enrollees aged 65 or above who were diagnosed with benign prostatic hyperplasia and received one of the study drugs between 2007-2020 were followed-up for the three outcomes. We used Cox regression analysis to assess the relative risk of each of the outcomes for each study drug compared to the most prescribed drug, tamsulosin, while controlling for demographic, socioeconomic and comorbidity factors. RESULTS AND CONCLUSIONS: The study analyzed 1.1 million patients for a mean follow-up period of 3.1 years from being prescribed one of the study drugs. For all outcomes, patients on tamsulosin were used as the reference for comparison. For mortality, alfuzosin was associated with 27% risk reduction (HR 0.73, 95%CI 0.68-0.78), and doxazosin with 6% risk reduction (HR 0.94, 95%CI 0.91-0.97). For Parkinson's disease, terazosin was associated with 26% risk reduction (HR 0.74, 95%CI 0.66-0.83), and doxazosin with 21% risk reduction (HR 0.79, 95%CI 0.72-0.88). For Alzheimer's disease, terazosin was associated with 27% risk reduction (HR 0.73, 95%CI 0.65-0.82), and doxazosin with 16% risk reduction (HR 0.84, 95%CI 0.76-0.92). Tadalafil was associated with risk reduction (27-40%) in all 3 outcomes. More research is needed to elucidate the underlying mechanisms of these observations. Given the availability of safer alternatives for treating benign prostatic hyperplasia, caution should be exercised when using tamsulosin in elderly patients, especially those with an increased risk of developing neurodegenerative diseases.

Effect of perioperative tamsulosin on successful ureteral access sheath placement and stent-related symptom relief: A double-blinded, randomized, placebo-controlled study.

PURPOSE: This study investigated the effect of administering tamsulosin before surgery on the successful insertion of a 12/14 French (F) ureteral access sheath (UAS) during the procedure, as well as the impact of preoperative and postoperative tamsulosin use on symptoms related to the ureteral stent. MATERIALS AND METHODS: This study was a randomized, single-center, double-blinded, placebo-controlled trial involving 200 patients who underwent unilateral retrograde intrarenal surgery. Patients received either tamsulosin (0.4 mg) or placebo 1 week before surgery until stent removal. Patients were randomly assigned to one of four groups. Group 1 received tamsulosin throughout the study period. Group 2 received tamsulosin before surgery and placebo after surgery. Group 3 received placebo before surgery and tamsulosin after surgery. Group 4 received placebo before and after surgery. The USSQ (Ureteral Stent Symptom Questionnaire) was completed between postoperative days 7 and 14 immediately before stent removal. RESULTS: A total of 160 patients were included in this analysis. Their mean age was 55.0±11.0 years, and 48 patients (30.0%) were female. In the group that received preoperative tamsulosin, the success rate of 12/14F UAS deployment was significantly higher than that of the preoperative placebo group (88.0 vs. 75.3%, p=0.038). Preoperative and postoperative tamsulosin did not significantly alleviate symptoms related to the ureteral stent. CONCLUSIONS: Our results revealed that preoperative administration of tamsulosin improved the success of larger-sized UAS, whereas preoperative and postoperative tamsulosin use did not significantly alleviate symptoms related to ureteral stents.

Risk of age-related macular degeneration in men receiving 5α-reductase inhibitors: a population-based cohort study.

BACKGROUND: Recent studies suggest that 5α-reductase inhibitors (5ARIs) for benign prostate hyperplasia (BPH) result in abnormal retinal anatomical alteration. OBJECTIVE: To compare age-related macular degeneration (AMD) incidence in BPH patients receiving 5ARIs or tamsulosin. DESIGN: Retrospective, population-based cohort study using new-user and active-comparator design. SETTING: General population. SUBJECTS: Males with BPH, newly receiving 5ARIs or tamsulosin from 2010 to 2018. METHODS: Data were extracted from Taiwan's National Health Insurance Research Database. We used Cox proportional hazards model with 1:4 propensity score (PS) matching, based on intention-to-treat analysis to determine the risk of incident AMD. Sensitivity analyses included an as-treated approach and weighting-based PS methods. We also separately reported the risks of incident AMD in patients receiving finasteride and dutasteride to determine risk differences among different 5ARIs. RESULTS: We included 13 586 5ARIs users (mean age: 69 years) and 54 344 tamsulosin users (mean age: 68.37 years). After a mean follow-up of 3.7 years, no differences were observed in the risk of incident AMD between 5ARIs and tamsulosin users [hazard ratio (HR): 1.06; 95% confidence intervals (95% CI): 0.98-1.15], with similar results from sensitivity analyses. However, increased risk of incident age-related macular degeneration was observed in patients receiving dutasteride [HR: 1.13; 95% CI: 1.02-1.25], but not in those receiving finasteride [HR: 0.99; 95% CI: 0.87-1.12], in the subgroup analyses. CONCLUSIONS: We found no difference between 5ARIs and tamsulosin regarding the incidence of AMD in BPH patients. However, the risk profiles for AMD differed slightly between dutasteride and finasteride, suggesting that the potency of androgen inhibition is a factor related to AMD incidence.

Population pharmacokinetics of tamsulosine in patients with benign prostatic hyperplasia.

PURPOSE: The study aimed to determine the typical clearance and volume of distribution values of tamsulosin in patients with benign prostatic hyperplasia (BPH), and to identify factors with a measurable impact on the drug's elimination. METHODS: This open-label, single-arm population pharmacokinetic study involved 65 adult men with BPH who had been on tamsulosin therapy for at least seven days. The steady-state serum concentrations of tamsulosin were measured using liquid chromatography-tandem quadrupole mass spectrometry. Population pharmacokinetic parameters, their variability, and influencing factors were estimated based on a two-compartment pharmacokinetic model using NONMEM software. RESULTS: The estimated tamsulosin clearance in BPH patients was 0.719 L/h, and the steady-state volume of distribution was 32 L. Neither renal nor liver function parameters had a statistically significant effect on tamsulosin clearance. However, a positive correlation was observed between hemoglobin levels and tamsulosin clearance in the BPH patient cohort. CONCLUSION: Our investigation reveals significant associations between tamsulosin pharmacokinetics and specific characteristics of patients with lower urinary tract symptoms (LUTS) due to BPH. The study highlights that tamsulosin clearance is associated with hemoglobin levels in patients with LUTS/BPH. This study underscores the importance of considering patient-specific factors when managing BPH treatment with tamsulosin, emphasizing associations rather than causative relationships.

Effect of α-blockers on Handgrip Test Response of Diastolic Blood Pressure in Hypertensive, Benign Hypertrophy of Prostate Patients in a Therapeutics Clinic, Kolkata: A Cross-sectional Study.

BACKGROUND: The isometric handgrip (IHG) test is commonly used to detect sympathetic autonomic dysfunction. Tamsulosin, approved for the management of symptomatic benign prostatic hyperplasia (BPH), acts as an antagonist for α1-adrenergic receptors (α1-AR), whereas prazosin, an α1 receptor blocker, being less selective than tamsulosin, is used as an antihypertensive agent clinically. Our objective was to investigate if there is a distinction in blood pressure (BP) increase during IHG exercise between individuals with essential hypertension taking tamsulosin compared to those taking prazosin. MATERIALS AND METHODS: A cross-sectional observational study was performed on 50 subjects receiving tablet prazosin and 47 subjects receiving tamsulosin, who were asked to undergo an IHG test. Pre- and posttest BP was recorded for both the groups, and the difference in diastolic BP (DBP) (delta DBP) was compared between the groups and to their respective baseline values. RESULTS: Post-IHG test, mean DBP was found to be 93.98 ± 9.13 mm Hg in the prazosin group and 101.00 ± 12.05 mm Hg in the tamsulosin group, respectively. The change of delta DBP in the tamsulosin group was significant, but the prazosin group showed an insignificant rise in DBP. CONCLUSION: Prazosin, being less selective than tamsulosin in terms of α1 receptor antagonism, showed suppression of BP during IHG. Tamsulosin demonstrates high selectivity for prostatic receptors while showing minimal affinity for vascular receptors. As a result, its impact on BP is expected to be minimal.

Association of Terazosin, Doxazosin, or Alfuzosin Use and Risk of Dementia With Lewy Bodies in Men.

BACKGROUND AND OBJECTIVES: Terazosin, doxazosin, and alfuzosin (Tz/Dz/Az) are α-1 adrenergic receptor antagonists that also bind to and activate a key adenosine triphosphate (ATP)-producing enzyme in glycolysis. It is hypothesized that the increase in energy availability in the brain may slow or prevent neurodegeneration, potentially by reducing the accumulation of alpha-synuclein. Recent work has suggested a potentially neuroprotective effect of the use of Tz/Dz/Az in Parkinson disease in both animal and human studies. We investigated the neuroprotective effects of Tz/Dz/Az in a closely related disease, dementia with Lewy bodies (DLB). METHODS: We used a new-user active comparator design in the Merative Marketscan database to identify men with no history of DLB who were newly started on Tz/Dz/Az or 2 comparator medications. Our comparator medications were other drugs commonly used to treat benign prostatic hyperplasia that do not increase ATP: the α-1 adrenergic receptor antagonist tamsulosin or 5α-reductase inhibitor (5ARI). We matched the cohorts on propensity scores and duration of follow-up. We followed up the matched cohorts forward to estimate the hazard of developing DLB using Cox proportional hazards regression. RESULTS: Men who were newly started on Tz/Dz/Az had a lower hazard of developing DLB than matched men taking tamsulosin (n = 242,716, 728,256 person-years, hazard ratio [HR] 0.60, 95% CI 0.50-0.71) or 5ARI (n = 130,872, 399,316 person-years, HR 0.73, 95% CI 0.57-0.93). while the hazard in men taking tamsulosin was similar to that of men taking 5ARI (n = 159,596, 482,280 person-years, HR 1.17, 95% CI 0.96-1.42). These results were robust to several sensitivity analyses. DISCUSSION: We find an association in men who are taking Tz/Dz/Az and a lower hazard of DLB compared with similar men taking other medications. When combined with the literature of Tz/Dz/Az on Parkinson disease, our findings suggest that glycolysis-enhancing drugs may be broadly protective in neurodegenerative synucleinopathies. A future randomized trial is required to assess these associations for causality. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that Tz/Dz/Az use reduces the rate of developing DLB in adult men.

Tamsulosin 0.8 mg daily dose in management of BPH patients with failed tamsulosin 0.4 mg monotherapy and unfit for surgical intervention.

AIM: This study aims to evaluate the effectiveness and safety of administering double-dose tamsulosin (0.8 mg) for treating patients with benign prostatic hyperplasia (BPH) who have not responded to the standard single dose of tamsulosin (0.4 mg) and are deemed unsuitable for transurethral resection (TUR) intervention. MATERIALS AND METHODS: Between November 2022 and July 2023, we prospectively analyzed 111 patients who were experiencing severe BPH symptoms. These patients received a double dose of tamsulosin for one month. We collected baseline characteristics such as age, body mass index, and underlying medical conditions. Various parameters including the International Prostate Symptom Score (IPSS), prostate-specific antigen (PSA) levels, prostate volume, peak urinary flow rate (Qmax), voided volume, and post-void residual volume were evaluated before and after treatment. RESULTS: All 111 patients completed the study. The mean age, PSA level, and prostate volume were 63.12 ± 4.83 years, 3.42 ± 0.93 ng/ml, and 50.37 ± 19.23 ml, respectively. Of these patients, 93 showed improvement in Qmax, post-void residual volume, and IPSS score (p-value = 0.001). The total IPSS score and total Qmax improved from 24.03 ± 2.49 and 7.72 ± 1.64 ml/sec to 16.41 ± 3.84 and 12.08 ± 2.37 ml/sec, respectively. CONCLUSION: Double-dose 0.8mg tamsulosin as an alpha-blocker therapy appears to be a viable temporary management option for BPH patients who have not responded to the standard single dose 0.4mg tamsulosin and are not suitable candidates for TUR intervention.

The alpha1A antagonist tamsulosin impairs memory acquisition, consolidation and retrieval in a novel object recognition task in mice.

Tamsulosin is an α1-adrenoceptor antagonist used to treat benign prostatic hyperplasia. This drug exhibits high affinity for α1A- and α1D-adrenoceptor subtypes, which are also expressed in the brain. While dementia symptoms have been reported after administration of tamsulosin in humans, studies on its effects on the rodent brain are still rare. The present study investigated the effects of tamsulosin (and biperiden, an amnesic drug) on cognitive performance in the object recognition task (ORT). Tamsulosin (0.001-0.01 mg/kg) was orally administrated in mice at three distinct time points: pre-training, post-training and pre-test session. Tamsulosin 0.01 mg/kg impaired object recognition regardless of when it was injected, whereas at lower doses did not affect mouse performance in the ORT. Biperiden also impaired acquisition and consolidation of object recognition in mice. Furthermore, the effects of tamsulosin on locomotion, motivation and anxiety were excluded as potential confounding factors. At all doses tested, tamsulosin did not alter distance moved, time spent exploring objects in the ORT, and anxiety-related behaviors in the elevated plus-maze test. By contrast, diazepam evoked a significant reduction of anxiety-like behaviours. In conclusion, tamsulosin impaired memory acquisition, consolidation and retrieval in an object recognition task in mice, thus affecting memory performance in a non-specific phase manner. These findings contribute to our understanding of the potential adverse effects of tamsulosin, and shed light on the role played by α1-adrenoceptors, particularly α1A- subtype, in cognitive processes.

Comparative efficacy and safety of alpha-blockers as monotherapy for benign prostatic hyperplasia: a systematic review and network meta-analysis.

Despite the availability of various drugs for benign prostatic hyperplasia (BPH), alpha(α)-blockers are the preferred first-line treatment. However, there remains a scarcity of direct comparisons among various α-blockers. Therefore, this network meta-analysis (NMA) of randomized controlled trials (RCTs) aimed to evaluate the efficacy and safety of α-blockers in the management of BPH. A comprehensive electronic search covered PubMed, Embase, Ovid MEDLINE, and Cochrane Library until August 2023. The primary endpoints comprised international prostate symptom score (IPSS), maximum flow rate (Qmax), quality of life (QoL), and post-void residual volume (PVR), while treatment-emergent adverse events (TEAEs) were considered as secondary endpoints. This NMA synthesized evidence from 22 studies covering 3371 patients with six kinds of α-blockers with 12 dose categories. IPSS has been considerably improved by tamsulosin 0.4 mg, naftopidil 50 mg and silodosin 8 mg as compared to the placebo. Based on the p-score, tamsulosin 0.4 mg had the highest probability of ranking for IPSS, PVR, and Qmax, whereas doxazosin 8 mg had the highest probability of improving QoL. A total of 297 adverse events were reported among all the α-blockers, silodosin has reported a notable number of TEAEs. Current evidence supports α-blockers are effective in IPSS reduction and are considered safer. Larger sample size with long-term studies are needed to refine estimates of IPSS, QoL, PVR, and Qmax outcomes in α-blocker users.

Incidence of Urinary Retention Following Posterior Spinal Fusion for Adolescent and Pediatric Scoliosis at a Single Academic Center: Is There a Role for Prophylactic Tamsulosin?

The purpose of this study is to better characterize patient- and surgery-specific parameters associated with postoperative urinary retention (POUR) and assess the impact of prophylactic Tamsulosin following posterior spinal fusion (PSF) for the management of scoliosis in pediatric and adolescent patients. All patients who underwent PSF for surgical correction of adolescent idiopathic scoliosis (AIS) and neuromuscular scoliosis (NMS) between 2015 and 2019 were retrospectively reviewed. Patients were stratified based on whether they received prophylactic Tamsulosin. Overall, POUR was reported in 3.7% (n = 10) of all patients in the study, although Tamsulosin was associated with a lower rate of POUR, and this did not reach statistical significance. Longer fusion constructs were identified as a risk factor for POUR and could help surgeons counsel families prior to surgery. This is the first study to assess the rate of POUR on AIS and NMS patients following PSF without epidural analgesia. (Journal of Surgical Orthopaedic Advances 33(1):010-013, 2024).

Optimal duration of medical expulsive therapy for lower ureteral stones: a critical evaluation.

To evaluate the optimal duration of Medical Expulsive Therapy (MET) application for distal ureteric stones on a time period based manner. 89 patients with 5-10 mm distal ureter stones received tamsulosin (0.4 mg) for MET and diclofenac sodium (75 mg) for analgesia. Patients were evaluated once a week for 4 weeks. Radiologic stone passage was evaluated by kidney ureter bladder (KUB) and ultasonography where non-contrast computed tomography (NCCT) was also performed if needed. While 23 cases (28.4%) were SF after first week, 23 were SF (28.4%) after 2 weeks, 9 cases (11.1%) after 3 and lastly 7 cases (8.6%) became SF after four weeks. Nineteen (23.5%) cases were not SF after 4 weeks. A positive relationship was found between the time period elapsed for stone passage and ureteral wall thickness (UWT) along with the degree of hydronephrosis. In addition, mean number of renal colics and emergency department (ED) visits were found to be higher in patients passing stones in the 4th week along with the ones who could not despite MET. SFR for distal ureteric stones sizing 5-10 mm was higher within the first 3 weeks under MET application. Thus, waiting for a longer period of time may result in increased analgesic and unnecessary MET treatment with increased risk of emergency department visits and additional costs as well. We believe that other options could be considered in such cases who are not SF at the end of the first 3 weeks.

Effect of different alpha-receptor antagonists on metabolic parameters: a head-to-head comparison.

PURPOSE: Although it is known that alpha-adrenergic receptor antagonists have positive effects on metabolic parameters such as glucose metabolism, lipid profile, and insulin sensitivity, it is unclear whether this is a class effect. Tamsulosin is reported to have adverse effects on glucose metabolism and insulin resistance, and this may be because of its lack of glycolysis-enhancing effect compared with other alpha-adrenergic receptor antagonists with glycolysis-enhancing effects such as doxazosin, terazosin, and alfuzosin. The aim of this study was to compare the effect of tamsulosin on metabolic parameters with another alpha-1 adrenergic receptor antagonist, doxazosin. METHODS: In this prospective, observational, controlled, 12-week clinical study, a total of 60 male patients aged ≥ 40 years who were first started on tamsulosin (n = 30; 0.4 mg/day, oral; mean age, 59.20 ± 8.97 years) or doxazosin (n = 30; 4 or 8 mg/day, oral; mean age, 58.50 ± 8.93 years) for benign prostatic hyperplasia (BPH) or lower urinary tract symptoms (LUTS) were enrolled. The groups were compared according to the changes in anthropometric and biochemical parameters (glycemia, lipid profile, and insulin sensitivity) at the end of treatment. RESULTS: In intragroup analyses, systolic blood pressure, diastolic blood pressure, total cholesterol, and HbA1c levels decreased significantly in the doxazosin group compared with baseline (p < 0.05 for all), while no significant change was observed in the tamsulosin group. In comparisons between groups, systolic blood pressure, total cholesterol, and low-density lipoprotein cholesterol levels showed a significant decrease in the doxazosin group compared with the tamsulosin group (percent change: - 6.68 ± 13.08 vs. 0.53 ± 11.02, p = 0.025; - 3.63 ± 9.56 vs. 4.02 ± 10.86, p = 0.005; and - 5.62 ± 18.18 vs. 5.24 ± 15.42, p = 0.015, respectively). CONCLUSION: Although these results do not support previous findings that tamsulosin has adverse effects on metabolic parameters, they suggest that doxazosin treatment may be a reason for preference in patients with BPH or LUTS accompanied by metabolic disorder.

Micro/nanofluidic device for tamsulosin therapeutic drug monitoring in patients with benign prostatic hyperplasia at point of care.

Discovering the balance between toxicity and efficacy for many drugs requires therapeutic drug monitoring (TDM) of their concentrations in the blood. Here, a hot-embossed microfluidic device with a new design integrated to a nanofracture is presented for purification of blood samples from numerous proteins and cells, allowing to the separation of small molecules from blood matrix. The device was used to separate and quantitatively detect tamsulosin drug after derivatization with fluorescamine reagent, allowing converting it from a neutral molecule into a charged fluorescent complex under the experimental conditions, and thus its separation by electrophoresis. The device is portable and easy operated, and the presented method showed good linearity (R2 = 0.9948) over a concentration range of 0.1-1 µg/mL. The relative standard deviation (RSD%) was below 10% (n = 3), indicating good precisions, and the limit of detection (LOD) and limit of quantitation (LOQ) values were estimated to be 0.1 and 0.55 µg/mL, respectively. Whole blood samples from 10 patients with benign prostatic hyperplasia (BPH) were analyzed, showing good percentage recoveries of tamsulosin in whole blood. This point-of-care (POC), low-cost method could increase the convenience of patients and doctors, make therapies safer, and make TDM available in different regions and places.

Semirigid ureteroscopy and tamsulosin therapy as dilatation methods before flexible ureteroscopy: evaluation and benefits.

OBJECTIVE: To evaluate the effect of semirigid ureteroscopy and tamsulosin therapy as dilatation methods before flexible ureteroscopy advancement to the renal collecting system. PATIENTS AND METHODS: This prospective study included patients with renal stones less than 2 cm who underwent retrograde flexible ureteroscopy and laser lithotripsy. The patients were randomized into two groups: group A patients were given a placebo for 1 week before flexible ureteroscopy, and group B patients were administered 0.4 mg of tamsulosin once daily for 1 week before surgery and underwent active dilatation using semirigid ureteroscopy before flexible ureteroscopy. The ability of the flexible ureteroscope to reach the collecting system in both groups during the same operative session was assessed. Operative outcomes and complications were collected and analyzed in both groups. RESULTS: A total of 170 patients were included in our study, with each group comprising 85 patients. In group B, the flexible ureteroscope successfully accessed the kidney in 61 patients, while in group A, the flexible ureteroscope was successful only in 28 cases (71.4% versus 32.9%). In group A, 33 (38.8%) patients had lower urinary tract symptoms compared to 17 (20.2%) patients in group B (P = 0.013). CONCLUSION: Using tamsulosin therapy and semirigid ureteroscopy as dilatation methods before flexible ureteroscopy increased the success of primary flexible ureteroscopy advancement to renal collecting system.

Medications Mostly Associated With Ejaculatory Disorders: Assessment of the Eudra-Vigilance and Food and Drug Administration Pharmacovigilance Databases Entries.

OBJECTIVE: To identify which medications are mostly associated with ejaculatory disorders through a disproportionality analysis. METHODS: The Food and Drug Administration Adverse Event Reporting System (FDA-FAERS) and the Eudra-Vigilance (EV) database were queried to identify medications more commonly associated to ejaculatory disorders from September 10, 2012 to June 1, 2023. Proportional Reported Ratios (PRRs) were computed for all the selected drugs. RESULTS: Overall, 7404 reports of ejaculatory disorders reports were identified, and of these, 6854 cases (92.6%) were attributed to ten specific medications. On FDA-FAERS and EV databases, Paroxetine and Tamsulosin were the main responsible of delayed ejaculation (103/448 events, 23.0%) and retrograde ejaculation (366/1033 events, 35.4%), respectively. Finasteride was mostly related to painful ejaculation and ejaculation failure, with 150 events (7.8%) and 735 events (38.4%) respectively. Within the group of high-risk medications, Sildenafil presented higher risk of ejaculatory disorders than Tadalafil (PRR=5.85 (95%CI 5.09-6.78), P < .01). CONCLUSION: Ten drugs were recognized to display significant reporting levels of ejaculatory disorders. Among them, Finasteride and Sildenafil were responsible for the most reports in FDA-FAERS and in EV databases, respectively. Physicians should thoroughly counsel patients treated with these drugs about the risk of ejaculatory disorders. Further integration into clinical trials is needed to enhance the applicability and significance of these results.

Tadalafil versus tamsulosin as combination therapy with 5-alpha reductase inhibitors in benign prostatic hyperplasia, urinary and sexual outcomes.

PURPOSE: To compare the urological and sexual outcomes of using either tamsulosin/finateride or tadalafil/finasteride as combination therapies in patients with large prostate. PATIENTS AND METHODS: Selection criteria included prostate volume > 40 ml and IPSS > 7. Patients with severe erectile dysfunction (IIEF-erectile functions ≤ 10) were excluded. Patients were randomized into group I (tamsulosin/finasteride) and group II (tadalafil/finasteride). The primary endpoint was to define urinary and sexual function changes (IPSS, IPSS-quality of life, urinary flow rates and IIEF domains) within each group. The secondary endpoint was to compare the treatment induced changes between both groups. RESULTS: At 4th and 12th weeks, 131 and 127 patients were available in both groups, respectively. Both groups showed significant LUTS improvement (IPSS changes: - 4.9 ± 2.7 and - 4.3 ± 2.9 at 4th week and - 6.1 ± 3 and - 5.4 ± 2.8 points by the 12th week in both groups, respectively). Group I had better average flow rates at both follow-up visits. Meanwhile, maximum flow rates were comparable in both groups at 12th week (13.5 ± 3.9vs. 12.6 ± 3.7, p > 0.05). In group I, all IIEF domains were significantly lowered at both visits (p < 0.05). Group II showed significant increase in IIEF-erectile function scores (1.3 ± 1.1 and 1.8 ± 1.2 at the 4th and 12th weeks) with a transient significant reduction of IIEF-orgasm and sexual desire noted only by the 4th week (- 0.8 ± 0.4 and - 0.6 ± 0.4, respectively). CONCLUSION: Within three months, both combinations are comparably effective in improving BPH related LUTS. Tamsulosin/finasteride provided significantly better Qmax only at 4th week. Tadalafil/finasteride had the advantage of improving sexual performance over the other combination.

Characteristics of α1-adrenoceptor antagonists-induced ejaculatory dysfunction on spontaneous seminal emission in rats.

Although α1-adrenoceptor (α1-AR) antagonists used to treat benign prostatic hyperplasia can cause ejaculation disorders, the aetiology of this adverse event is still controversial. Therefore, we investigated the effects of antagonists with different affinities for α1-AR subtypes on ejaculatory function and their mechanisms of action in normal rats. In the spontaneous seminal emission (SSE) test, systemically administered prazosin, terazosin, tamsulosin and naftopidil decreased the weight of ejaculated seminal material in a dose-dependent manner; the potency order was as follows: tamsulosin > terazosin > prazosin > naftopidil. The selective α1D-AR antagonist BMY7378 had no effect on SSE. Intrathecal tamsulosin and naftopidil did not inhibit SSE. Tamsulosin, the most potent, was ineffective as a single dose and significantly increased seminal vesicle fluid in rats treated for 2 weeks but did not significantly change retrograde ejaculation. These results indicated that the difference in inhibitory potency of the five α1-AR antagonists against SSE was due to the involvement of α1A-AR subtypes. Our results further suggested that α1-AR antagonist-induced ejaculatory dysfunction at the peripheral level was mainly due to the loss of seminal emission, although some retrograde ejaculation may also be involved.

Effect of tamsulosin on urethral tone in healthy male cats.

OBJECTIVES: Alpha-adrenergic antagonists are commonly used to prevent recurrent urethral obstruction in cats with mixed reports of efficacy. No published data on tamsulosin use in cats are available. The objective of this study was to measure changes in urodynamic parameters and blood pressure in five healthy male cats before and after administration of tamsulosin orally for 4 and 10 days. METHODS: Five young healthy adult male cats from a research colony were administered tamsulosin at 0.1 mg/cat PO q24h for 10 days. Urethral pressure profile and blood pressure measurements were performed before treatment and approximately 6 h after treatment on days 4 and 10. Maximum urethral closure pressure (MUCP) for the prostatic and penile urethra, functional urethral length (FPL), functional area (FA) and systolic blood pressures were recorded and compared between the time points. RESULTS: Significant changes in blood pressure on day 4 (121.1 mmHg ± 20.2 mmHg) and on day 10 (112.6 mmHg ± 14.9 mmHg) compared with day 0 (141.1 mmHg± 33.4 mmHg) were not detected (P = 0.18) in anesthetized cats. No significant difference in MUCP, FA or FPL measurements were detected among baseline, day 4 and day 10 of treatment. Hematuria and transient pollakiuria were induced in two cats with 3.5 Fr urethral catheters. CONCLUSIONS AND RELEVANCE: Tamsulosin at 0.1 mg/cat PO q24h did not induce hypotension in healthy cats. Urodynamic testing performed 6 h after the tamsulosin pill was administered did not detect consistent decreases in urodynamic functions induced by tamsulosin. Repeated catheterization of tom cats with 3.5 Fr catheters may induce significant urethral trauma.