Silodosin: An Update on Efficacy, Safety and Clinical Indications in Urology
Silodosin determines smooth muscle relaxation in bladder and prostate tissues, increases bladder blood flow in conditions of chronic bladder ischemia and regulates the activity of transcriptional factors responsible for stromal growth and prostate hyperplasia. Phase III trials have already demonstrated the efficacy and safety of silodosin in the treatment of patients bothered by lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH).
We aimed to describe the rationality for the use of silodosin and to summarize the current literature on the use of Silodosin for the treatment of LUTS.
PubMed and Web of Science were queried with the terms: ‘silodosin’ in combination (AND) with the terms ‘lower urinary tract symptoms’, ‘LUTS’, ‘pathophysiology’, ‘symptoms’ OR ‘therapy’. Studies published in the last 10 years (2007–2017) in adults and core clinical journals in English were included.
Silodosin 8 mg once-daily was superior to placebo in improving IPSS total score, voiding subscore, storage subscore and QoL score, and at least as effective as tamsulosin 0.4 mg once-daily in all the efficacy analyses. In addition, studies assessing the effect on urodynamic parameters showed that silodosin determined a higher improvement in the bladder outlet obstruction index compared to other alpha1 adrenergic receptor antagonists. Concerning the safety profile, long-term data (after 9 months of treatment) confirmed the limited effect of silodosin on the cardiovascular and gastrointestinal systems. Although ejaculatory disorders represented the main complaint of patients taking silodosin, the discontinuation rate due to this condition remained low even in a long-term follow-up study (7.5%). Encouraging findings showed that silodosin may be administered as a medical expulsive therapy for promoting spontaneous stone passage of distal ureteral stones < 10 mm, to relieve LUTS in patients who underwent prostate cancer brachytherapy and to increase the likelihood of successful trials without a catheter in patients experiencing acute urinary retention.
Silodosin is one of the drugs approved for the treatment of BPH, being highly effective in improving not only LUTS but also urodynamic parameter impairments secondary to BPH. Moreover, it has shown efficacy as medical expulsive therapy for distal ureteral stones in previous prospective randomized trials.
Sponsorship for this study and article processing charges were funded by Recordati.
KeywordsAcute urinary retention Benign prostatic hyperplasia BPH Brachytherapy Lower urinary tract symptoms LUTS Silodosin Ureteral stone
Sponsorship for this study and article processing charges were funded by Recordati. All authors had full access to all of the data in this study and take complete responsibility for the integrity of the data and accuracy of the data analysis.
All named authors meet the International Committee of Medical Journal Editors (ICMJE) criteria for authorship for this article, take responsibility for the integrity of the work as a whole, and have given their approval for this version to be published.
Luca Villa has received research support, consultancy and lecturer honoraria in the field of α1-adrenoceptors from Recordati. Umberto Capitanio has received research support, consultancy and lecturer honoraria in the field of α1-adrenoceptors from Recordati. Andrea Salonia has received research support, consultancy and lecturer honoraria in the field of α1-adrenoceptors from Recordati. Francesco Montorsi has received research support, consultancy and lecturer honoraria in the field of α1-adrenoceptors from Recordati. Paolo Capogrosso, Alberto Martini and Alberto Briganti have nothing to disclose.
Compliance with Ethics Guidelines
This article is based on previously conducted studies and does not contain any studies with human participants or animals performed by any of the authors.
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