Silodosin versus naftopidil in the treatment of premature ejaculation: A prospective multicenter trial

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.

Current and emerging treatment options for premature ejaculation

Premature ejaculation (PE) is a prevalent male sexual dysfunction. Current standard treatment regimens include behavioural therapies, topical anaesthetics, dapoxetine and other selective serotonin reuptake inhibitors (SSRIs). Most of the pharmacotherapeutic options target neurotransmitters (such as serotonin and oxytocin) that have a role in the ejaculation mechanism. However, these treatments are mildly effective and only provide a temporary delay in the ejaculation latency time, and PE recurs when the treatment is stopped. Thus, a treatment for PE is urgently needed and research is ongoing to find the ideal PE therapy. The efficacy and safety of topical anaesthetics and SSRIs in delaying ejaculation have been confirmed in many well-designed controlled trials. Both preclinical and clinical studies on new-generation SSRIs are ongoing. Moreover, promising results came from clinical trials in which the efficacy of on-demand PE therapies targeting neurotransmitters other than serotonin, such as α1-adrenoceptor antagonists and oxytocin antagonists, was assessed. Surgical intervention and neuromodulation have been proposed as potential treatment options for PE; however, current PE guidelines do not recommend these treatments owing to safety concerns.

Evolving Role of Silodosin for the Treatment of Urological Disorders – A Narrative Review

Use of α-androgenic receptor blockers remains a mainstay therapeutic approach for the treatment of urological diseases. Silodosin is recommended over other α-blockers for the treatment of lower urinary tract symptoms (LUTS) and benign prostate hyperplasia (BPH), due to its high α_1A uroselectivity. Current research data suggest that silodosin is efficacious in the management of various urological diseases. Thus, we herein review the current evidence of silodosin related to its efficacy and tolerability and appraise the available literature that might ultimately aid in management of various urological conditions at routine clinical practice. Literature reveals that silodosin is beneficial in improving nocturia events related to LUTS/BPH. Silodosin exerts effect on relaxing muscles involved in detrusor obstruction, therefore prolonging the need for patients undergoing invasive surgery. Silodosin treatment, either as a monotherapy or combination, significantly improves International Prostate Symptom Score (IPSS) including both storage and voiding symptoms in patients with BPH/LUTS. Patients on other treatment therapies such as phosphodiesterase 5 inhibitors or other α-blockers are well managed with this drug. Steadily, silodosin has proved beneficial in the treatment of other urological disorders such as chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), overactive bladder/acute urinary retention (AUR), premature ejaculation (PE), and prostate cancer post brachytherapy-induced progression. In patients with distal ureteral stones, silodosin treatment is beneficial in decreasing stone expulsion time without affecting stone expulsion rate or analgesic need. Moreover, there were significant improvements in intravaginal ejaculation latency time, quality of life scores, and decrease in PE profile among patients with PE. Silodosin has also demonstrated promising results in increasing the likelihood of successful trial without catheter in patients with AUR and those taking antihypertensive drugs. Reports from Phase II studies have shown promising role of silodosin in the treatment of CP/CPPS as well as facilitating ureteral stone passage. From the robust data in this review, further silodosin treatment strategies in the management of different urological conditions need to be focused on.

An update on the treatment of premature ejaculation: A systematic review

To analyse the current therapeutic options for patients with premature ejaculation (PE) and highlight their mechanism(s) of action, effectiveness, advantages and limitations. A literature search was conducted using the PubMed database searching for articles exploring different PE treatment modalities. A Preferred Reporting Items for Systemic Reviews and Meta-Analyses (PRISMA) approach was used to report the results of the literature search. A total of 149 articles were included in this review. The currently available treatment methods for PE include behavioural therapy, local anaesthetics, tricyclic antidepressants, selective serotonin reuptake inhibitors, and selective phosphodiesterase inhibitors. Most PE treatments are either experimental or used off-label. New treatments are certainly warranted to overcome this exasperating sexual dysfunction.

Abbreviations: AIPE: Arabic Index of Premature Ejaculation; CNS: central nervous system; CYP: cytochrome P450; ED: erectile dysfunction; FDA: United States Food and Drug Administration; H1: histamine receptors; 5-HT: 5-hydroxytryptamine; IELT: The intravaginal ejaculation latency time; IPE: Index of Premature Ejaculation; M1: muscarinic receptors; OCD: obsessive–compulsive disorder; PDE5: phosphodiesterase type 5; PE: premature ejaculation; PEP: Premature Ejaculation Profile; PRO: patient-reported outcome; RCT: randomised controlled trial; SS: Severance Secret (cream); SSRIs: selective serotonin reuptake inhibitors; TCAs: tricyclic antidepressants

Sexual Incentive Motivation and Copulatory Behavior in Male Rats Treated With the Adrenergic α2-Adrenoceptor Agonists Tasipimidine and Fadolmidine: Implications for Treatment of Premature Ejaculation

BACKGROUND

Premature ejaculation is the most common sexual dysfunction in young men, and it often leads to reduced relationship satisfaction and quality of life.

AIM

To determine the role of central and peripheral α₂-adrenoceptors in the control of ejaculation and sexual incentive motivation in rats.

METHODS

Sexual incentive motivation was studied in a large arena in which a male subject could choose between approaching and remaining close to a sexually receptive female or another male. Sexual behavior was studied in standard observation cages in which a male was allowed to freely interact with a receptive female for 30 minutes. Two highly selective agonists at the α₂-adrenoceptors, tasipimidine and fadolmidine, were administered before the tests. Low peripheral doses of fadolmidine have been reported to have effects mainly outside of the central nervous system, whereas at large doses also the central effects are evident.

OUTCOMES

The time spent close to the receptive female in relation to the time spent with the male and measures of ambulatory activity were obtained from the test for sexual incentive motivation, while the habitual parameters of sexual behavior were recorded with the copulation test.

RESULTS

Tasipimidine prolonged ejaculation latency and the interintromission interval at the dose of 200 µg/kg when data from fast-ejaculating rats were used. No other sexual parameter was modified. A dose of 100 µg/kg was ineffective. There was no consistent effect on sexual incentive motivation, although modest sedation was observed. Fadolmidine, a drug that does not easily penetrate the blood-brain barrier, had no effect on sexual incentive motivation at any of the doses used (3, 30, and 100 µg/kg). The largest dose had clear sedative effects. The lower doses had no systematic effect on sexual behavior, not even when only fast or very fast ejaculating males were analyzed.

CLINICAL TRANSLATION

The findings are relevant to the search for treatments for premature ejaculation that are specific enough to selectively delay ejaculation.

STRENGTHS & LIMITATIONS

The procedures used here are standard in the field and yield the most reliable data. Whether the effects observed in male rats are directly transferrable to men can only be determined through clinical studies.

CONCLUSION

The observation that drugs acting at central but not peripheral α₂-adrenoceptors prolong ejaculation latency without affecting any other parameter of sexual behavior or sexual incentive motivation suggests that this kind of drug may be suitable for treating premature ejaculation. Jyrki L., Elisa V.-A., Xi C., et al. Sexual Incentive Motivation and Copulatory Behavior in Male Rats Treated With the Adrenergic α₂-Adrenoceptor Agonists Tasipimidine and Fadolmidine: Implications for Treatment of Premature Ejaculation. J Sex Med 2021;18:1677-1689.

Premature ejaculation in patients with lower urinary tract symptoms: a systematic review

Lower urinary tract symptoms (LUTS) refer to a group of symptoms related to bladder, prostate, and urethra. LUTS are common in men and the severity increases with age. LUTS are frequently associated with sexual dysfunction, such as premature ejaculation (PE), standing as the most common sexual dysfunction in men. Both LUTS and PE cause distress and dissatisfaction for the patient and his partner. This systematic review aims to determine the relationship between LUTS and PE in men. Two reviewers independently conduct a literature search in five online databases (PubMed, Scopus, Proquest, ClinicalKey, and ScienceDirect). In addition, reviewers also reviewed the reference list of chosen articles to identify additional relevant studies. Twelve articles were included in this systematic review that consists of one cohort study and 11 cross-sectional studies. The total scores of each identified study ranged from "poor" to "good." The prevalence of PE in LUTS ranged from 12 to 77%. Most of the studies showed a significant relationship between LUTS and PE. PE is more common in older age with the peak prevalence in age of 60-69 years old. There is a possible association between PE and LUTS. Further research using cohort or case-control study design on this topic is needed.

Changing Aspects of Male Sexual Functions Accompanying Treatment of Benign Prostatic Hyperplasia With Silodosin 8 mg Per Day

BACKGROUND

Alpha-adrenergic antagonist treatment for benign prostatic hyperplasia (BPH) and drug-related sexual side effects are frequent in aging men.

AIM

To investigate functional changes in erectile and ejaculatory aspects of male sexuality under Silodosin 8 mg per day treatment for BPH.

METHODS

Sexually active patients diagnosed with BPH and who initiated Silodosin treatment were the subjects of the study. The International Prostate Symptom Score, premature ejaculation patient profile (PEP-male) questionnaire, Sexual Health Inventory for Men (SHIM) questionnaire, and estimated intravaginal ejaculation latency time (IELT) values of the participants were used to evaluate sexual functions. Data evaluation was performed in 8 urology clinics retrospectively.

OUTCOMES

Participant ratings for SHIM, PEP, and estimated IELT were the primary outcome measures in the study.

RESULTS

Among 187 recruited patients, data of 98 patients, who completed the trial period in the study, were eligible. The median age of the eligible participants who completed the trial period for 3 months was 59.5 years (range 45-82). 16 patients of 187 (8%) reported a desire for drug withdrawal for anejaculation during the recruitment period. 46 (46.9%) and 49 (50%) patients reported anejaculation in the first and third month of the treatment, respectively. De novo erectile dysfunction was noticed in 15 patients (15.3%). There was a significant increase in the estimated IELT of subjects in both the first (P = .01) and third (P = .002) month. SHIM-1 (P = .008), SHIM-total (P = .009), and PEP scores (P = .008) were also improved in the third month of the treatment. Neither baseline patient characteristics nor changes in the International Prostate Symptom Score after treatment predicted final outcomes with multivariable analysis. The subgroup analysis of participants who reported "anejaculation" also revealed better outcomes compared with participants ejaculating naturally in the third month as per SHIM ratings.

CLINICAL IMPLICATIONS

Despite several male patients having dry orgasms due to Silodosin-induced anejaculation, the majority experienced improved erectile function.

STRENGTHS & LIMITATIONS

The present study demonstrated pioneering results while investigating both erectile and ejaculatory dimensions of the male sexual function during Silodosin treatment for BPH. However, lack of partner evaluation, low follow-up rates, and lack of knowledge about reasons why subjects are lost to follow-up after drug initiation have limited our interpretation.

CONCLUSION

Most patients using Silodosin 8 mg per day for BPH treatment experienced improvement in their erectile function, estimated IELT, and premature ejaculation profile in the third month of the treatment. Underlying mechanisms and reasons for individual differences necessitate further investigation. Cihan A, Kazaz İO, Yıldırım Ö, et al. Changing Aspects of Male Sexual Functions Accompanying Treatment of Benign Prostatic Hyperplasia With Silodosin 8 mg Per Day. J Sex Med 2020;17:1094-1100.

Progresses in pharmaceutical and surgical management of premature ejaculation

OBJECTIVE

Premature ejaculation (PE) is regarded as one of the most common male sexual dysfunctions. This review introduced several pharmaceutical and surgical methods for the management of PE. The definition, etiology, behavioral, and psychological therapy of PE were also discussed.

DATA SOURCES

"Premature," "ejaculation," or "sexual dysfuction" were used as the medical subject headings (MeSH) to obtain relevant articles before June 2019 on Pubmed, Google Scholar and CNKI. Most articles used were written in English and several Chinese articles were also cited.

STUDY SELECTION

Full-text articles of retrospective/prospective/randomized controlled trials were analyzed. Animal experiments and letters were excluded.

RESULTS

There are four PE sub-types: lifelong PE, acquired PE, natural variable PE, and subjective PE. Behavioral therapy, psychotherapy, medication, topical anesthetics, and surgery are currently used for the treatment of PE. However, all the above treatments have limitations. Therefore, novel ways should be investigated to more efficiently control PE.

CONCLUSIONS

The pharmaceutical therapy that is currently being used in clinical practice for the management of PE is still the main choice globally due to its good efficacy. Surgery may be a choice for patients who are resistant to medication. However, it should be performed cautiously.

Clinical review of ejaculatory dysfunction

BACKGROUND

Ejaculatory dysfunction (EjD) is a complex pathological condition compared to erectile dysfunction (ED). A definitive classification of EjD is not established, and treatment is often delayed. Owing to its association with infertility, EjD is a serious concern, particularly in men of reproductive age.

METHODS

The authors performed a literature search to identify the latest articles and overseas guidelines for review.

RESULTS

Our new classification categorizes men into two groups as follows: (1) men with inability to ejaculate (retrograde ejaculation, anejaculation, intravaginal ejaculatory dysfunction) and (2) men requiring an abnormal time for ejaculation (premature ejaculation, delayed ejaculation). In Japan, the number of men presenting with an inability to ejaculate is greater than those presenting with premature ejaculation. Pharmacotherapy is the first-line treatment for the management of these EjD patients. Behavioral therapy is added to pharmacotherapy depending on the case. Penile vibratory stimulation or electroejaculation is indicated in some men with retrograde ejaculation and anejaculation. In cases who hope for a baby, assisted reproductive technology should be simultaneously considered not to waste time.

CONCLUSION

It is important to distinguish between EjD and ED and accurately diagnose the type of EjD for optimal treatment of this condition.