Post-SSRI Sexual Dysfunction (PSSD): Biological Plausibility, Symptoms, Diagnosis, and Presumed Risk Factors

Orgasms, sexual pleasure, and opioid reward mechanisms

INTRODUCTION

Sexual activity produces pleasure related to sexual arousal, desire, and genitosensory and erogenous stimulation. Orgasms produce a whole brain and body rush of ecstatic pleasure followed by relaxation and refractoriness. This pleasure results from the activation of neurochemical reward pathways in the brain. This is differentiated by spinal pathways that control climax, the particular motor movements of the pelvic floor and the experience of tension release.

OBJECTIVES

To relate the activation of key neurochemical reward and bonding systems, notably dopamine, oxytocin, and opioids, to the pleasure of sexual activity in general and orgasms in particular.

METHODS

A narrative review of the neurochemical and neuroanatomical mechanisms activated during sexual stimulation and orgasm in rats and humans, and how they are related overall to the generation of sexual pleasure and reward.

RESULTS

Appetitive sexual pleasure involves the activation of dopamine and oxytocin release in hypothalamic and mesolimbic regions that regulate sexual arousal and desire, and are reinforced by localized opioid activity. Orgasms are thought to result in part from a massive release of opioids into these regions that inhibits dopamine and oxytocin transmission, but that initiates molecular changes to sensitize both systems and induce sexually conditioned place and partner preferences. Serotonin is also activated at orgasm and contributes to feelings of satiety and refractoriness. Orgasm disorders are distressing, cause resentment and conflict in a relationship, and diminish overall sexual health and well-being.

CONCLUSIONS

Orgasms are an important component of sexual pleasure for humans and perhaps all vertebrates. Endogenous opioids like β-endorphin that bind to mu opioid receptors are likely responsible for sexual pleasure and reward.

Mechanism of Traditional Chinese Medicine extract in the treatment of diabetic erectile dysfunction

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetic erectile dysfunction (DED) is a prevalent but often overlooked microvascular complication of type 2 diabetes mellitus (T2DM), with strong associations to cardiovascular disease. The pathophysiology of erectile dysfunction (ED) in T2DM patients is more intricate than in non-diabetic individuals, likely involving multiple pathogenic mechanisms such as endothelial dysfunction, vascular alterations, neuropathy, and oxidative stress. Traditional Chinese Medicine (TCM) has long been utilized in the management of DED, drawing on an extensive body of clinical experience. In TCM, DED is typically attributed to imbalances such as renal yang deficiency or insufficiencies in qi and blood. Herbal therapies within the TCM framework offer a multifaceted approach to treatment, targeting not only the replenishment of kidney yang and the regulation of qi and blood but also incorporating strategies for glycemic control and renal protection. This holistic approach has demonstrated effectiveness in alleviating erectile dysfunction in diabetic patients, thereby improving quality of life. However, the complexity of Chinese herbal formulations, with their diverse bioactive constituents, complicates the identification of specific active compounds and the mechanistic understanding of their therapeutic actions. This complexity has contributed to ongoing skepticism regarding the clinical utility of TCM and herbal remedies in the treatment of DED.

AIM OF THE STUDY

This study aimed to investigate the pathological mechanisms underlying the therapeutic effects of TCM in the treatment of DED, with a specific focus on the associated signaling pathways. By elucidating these mechanisms, the study seeks to provide a scientific basis for novel therapeutic strategies and enhance the viability of TCM-based approaches for DED management. Future research should prioritize the development of efficacious Chinese patent medicines tailored for the treatment of DED.

METHODS

This study utilizes keywords such as "diabetic erectile dysfunction", "signaling pathways", "traditional Chinese Medicine", "bioactive compounds", "herbal", "herbal monomers", and "herbal extracts" to conduct a comprehensive literature search in databases including Embase, PubMed, Web of Science, CNKI, Wanfang, and VIP, spanning all relevant publications up to February 2024.

RESULTS

It has been demonstrated that TCM extract can treat the DED by influencing the signaling pathways involved.

CONCLUSION

A comprehensive literature review was conducted across multiple databases, followed by rigorous screening, exclusion, summarization, synthesis, and analysis of relevant studies. The results indicate that TCM for DED primarily targets key pathological features, including endothelial dysfunction, vascular and neural abnormalities, and oxidative stress. The underlying mechanisms involve the NO/cGMP, eNOS, and PI3K/Akt/mTOR signaling pathways, contributing to significant improvements in erectile function. These findings provide a scientific basis for the use of TCM in DED, offering viable therapeutic options and innovative strategies to advance TCM-based treatment approaches. Furthermore, TCM exhibits notable potential in mitigating the pathological progression of DED. The pharmacological mechanisms and molecular signaling pathways of TCM extracts have been extensively investigated, underscoring their high value for clinical research and therapeutic development.

The antidepressants and sexual dysfunction: a pharmacovigilance-pharmacodynamic study of the FDA adverse event reporting system

BACKGROUND

Sexual dysfunction (SD) is a commonly occurring yet often underestimated adverse event associated with the use of antidepressants. This study aimed to analyze the reporting of SD associated with the use of antidepressants in comparison with one another, and to explore potential receptor mechanisms based on the real-world data from the Food and Drug Administration Adverse Event Reporting System (FAERS).

METHODS

Disproportionality analysis was conducted based on FAERS reports (2004 Q1 to 2024 Q2) using reporting odds ratios (ROR) and information components (IC) methods. Spearman correlation analysis was performed to explore the relationship between ROR and the related receptor-binding properties.

RESULTS

In total, 233 significant signals involving 9767 cases were included. The analysis confirmed that the selective serotonin reuptake inhibitors and serotonin-norepinephrine reuptake inhibitors exhibited significant signals, consistent with previous research. Additionally, unexpected signals were detected for vortioxetine (ROR = 13.60), suggesting a potential risk despite its low reported incidence rates of SD. Spearman correlation analysis revealed potential effects for the binding affinities of serotonin transporter, 5-HT1B, and 5-HT2A receptors on reduced sexual desire.

CONCLUSIONS

The present investigation has detected new and unexpected signals of antidepressant-related SDs. Further research is needed to validate and clarify the observed associations.

Prebiotic inulin alleviates anxiety and depression-like behavior in alcohol withdrawal mice by modulating the gut microbiota and 5-HT metabolism

BACKGROUND

Alcohol dependence (AD) is a common psychiatric disorder, often accompanied by anxiety and depression. These comorbidities are linked to disturbances in serotonin (5-HT) metabolism and gut microbiota dysbiosis. Clinical studies suggest that inulin, a prebiotic, can alleviate anxiety and depression in AD patients by affecting the gut microbiota, although the mechanisms remain unclear.

PURPOSE

The purpose of this study is to investigate the potential mechanisms by which inulin, a prebiotic, improves anxiety and depression-like behaviors in AD withdrawal mice. This research is based on the drug and food homology and intestinal treatment of encephalopathy, with the goal of developing new clinical strategies for AD treatment.

STUDY DESIGN

For this purpose, fecal samples from AD patients were analyzed to identify microorganisms associated with AD. An AD withdrawal mouse model was created, with inulin as the intervention and fluvoxamine maleate as the control. Techniques such as 16S microbiome sequencing and UPLC-TQMS-targeted metabolomics were used to assess gut microbiota, short-chain fatty acids (SCFAs) levels, and 5-HT metabolism.

METHODS

The AD withdrawal model was built using the "Drinking-in-the-dark" protocol over 6 weeks. Inulin (2 g/kg/day) and fluvoxamine maleate (30 mg/kg/day) were administered for 4 weeks. The open field test, forced swim test, and tail suspension test were used to evaluate anxiety and depression-like behaviors in mice. ELISA and qRT-PCR assessed 5-HT metabolism in the colon, blood, and prefrontal cortex, while 16S microbiome sequencing analyzed changes in gut microbiota and UPLC-TQMS examined SCFAs levels. Immunohistochemistry was used to study intestinal barrier integrity.

RESULTS

AD patients showed reduced SCFA-producing bacteria such as Faecalibacterium and Roseburia. In mice, AD withdrawal led to anxiety and depression-like behaviors, disrupted 5-HT metabolism, and gut microbiota dysbiosis. Inulin supplementation alleviated these behaviors, increased 5-HT and 5-hydroxytryptophan (5-HTP) levels, upregulated colonic tryptophan hydroxylase 1 (TPH1) expression, and promoted the growth of beneficial bacteria such as Faecalibacterium and Roseburia, while also increasing SCFAs levels.

CONCLUSION

Inulin increases the abundance of Faecalibacterium and Roseburia, enhances SCFAs production, and regulates 5-HT metabolism, improving anxiety and depression-like behaviors in AD withdrawal mice. These findings suggest that inulin may serve as a nutritional intervention for mental health in AD patients by targeting the microbiome-gut-brain axis.

Frequency of self-reported persistent post-treatment genital hypoesthesia among past antidepressant users: a cross-sectional survey of sexual and gender minority youth in Canada and the US

PURPOSE

Persistent post-treatment genital hypoesthesia (PPTGH) is a primary symptom of post-SSRI sexual dysfunction (PSSD), an iatrogenic syndrome characterized by enduring sexual dysfunction following the discontinuation of some antidepressants. We aimed to estimate the frequency of PPTGH among past users of psychiatric treatments, particularly antidepressants.

METHODS

We used a subsample of UnACoRN, a US/Canada survey of sexual and gender minority youth aged 15 to 29. We included participants with a history of psychiatric drug use. We excluded individuals with genital surgeries or without sexual experience. The analysis involved chi-square tests for initial group comparisons, post hoc tests for multiple comparisons, and logistic regression among those who had stopped taking medication. We exponentiated the regression to estimate the odds of PPTGH by drug type, adjusting for age, sex-assigned-at-birth, hormone treatment, and depression severity in three nested models.

RESULTS

574 of 2179 survey participants reported genital hypoesthesia. They were older and more likely to report male sex assignment at birth, hormonal therapy history, and psychiatric drug history. The frequency of PPTGH among antidepressant users was 13.2% (93/707) compared to 0.9% (1/102) among users of other medications; adjusted odds ratio: 14.2 (95% CI: 2.92 to 257).

CONCLUSION

Antidepressant discontinuation is strongly associated with PPTGH in the US and Canada where SSRI/SNRI medications account for 80% of antidepressant prescriptions. We call for standardized international warnings and transparent, informed consent. Future research should expand upon our efforts to estimate the risk of PSSD by including all the proposed diagnostic criteria, including documentation of temporal changes in PSSD-related symptoms before and after treatment (≥3 months).

Sexual dysfunction and commonly used drugs in neurology

Sexual dysfunction is common in men and women with neurological diseases. Medications used in neurology can cause sexual dysfunction independently of the disease process and this may adversely affect patients' quality of life. This review focuses on medications commonly prescribed to neurological patients that may contribute to altered sexual function, and discusses how they may differ in men and women.

Exploring adverse events of Vilazodone: evidence from the FAERS database

OBJECTIVE

This study aims to conduct an exhaustive evaluation of Vilazodone's safety in clinical application and to unearth the potential adverse event (AE) risks associated with its utilization based on FDA Adverse Event Reporting System (FAERS) database.

METHODS

This research employed data spanning from the first quarter of 2011 to the third quarter of 2023 from the FAERS database. Various signal detection methodologies, including the Reporting Odds Ratio (ROR), Proportional Reporting Ratio (PRR), Bayesian Confidence Propagation Neural Network (BCPNN), and Empirical Bayesian Geometric Mean (EBGM), were utilized to ascertain the correlation between Vilazodone and specific AEs.

RESULTS

The study compiled a total of 17,439,268 reports of drug AEs, out of which 5,375 were related to Vilazodone. Through signal mining, 125 Preferred Terms (PTs) encompassing 27 System Organ Classes (SOCs) were identified. The findings indicated a higher prevalence among females and patients within the 45 to 65 age bracket. The principal categories of AEs included Psychiatric disorders, Nervous system disorders, and Gastrointestinal disorders, with prevalent incidents of Diarrhoea, Nausea, and Insomnia. Moreover, the study identified robust signals of novel potential AEs, notably in areas such as sleep disturbances (Sleep paralysis, Hypnagogic hallucination, Rapid eye movements sleep abnormal, Sleep terror, Terminal insomnia, Tachyphrenia), sexual dysfunctions (Female orgasmic disorder, Orgasm abnormal, Disturbance in sexual arousal, Spontaneous penile erection, Anorgasmia, Sexual dysfunction, Ejaculation delayed), and other symptoms and injuries (Electric shock sensation, Violence-related symptom, Gun shot wound).

CONCLUSION

Although Vilazodone presents a positive prospect in the management of MDD, the discovery of AEs linked to its use, particularly the newly identified potential risks such as sleep and sexual dysfunctions, necessitates heightened vigilance among clinicians.

Post-Finasteride Syndrome And Post-Ssri Sexual Dysfunction: Two Clinical Conditions Apparently Distant, But Very Close

Post-finasteride syndrome and post-SSRI sexual dysfunction, are two poorly explored clinical conditions in which men treated for androgenetic alopecia with finasteride or for depression with SSRI antidepressants show persistent side effects despite drug suspension (e.g., sexual dysfunction, psychological complaints, sleep disorders). Because of some similarities in the symptoms, common pathological mechanisms are proposed here. Indeed, as discussed, clinical studies and preclinical data obtained so far suggest an important role for brain modulators (i.e., neuroactive steroids), neurotransmitters (i.e., serotonin, and cathecolamines), and gut microbiota in the context of the gut-brain axis. In particular, the observed interconnections of these signals in these two clinical conditions may suggest similar etiopathogenetic mechanisms, such as the involvement of the enzyme converting norepinephrine into epinephrine (i.e., phenylethanolamine N-methyltransferase). However, despite the current efforts, more work is still needed to advance the understanding of these clinical conditions in terms of diagnostic markers and therapeutic strategies.

Selective serotonin reuptake inhibitors, post-treatment sexual dysfunction and persistent genital arousal disorder: A systematic review

PURPOSE

Adverse effects of selective serotonin reuptake inhibitors (SSRIs) on sexual function have been an important area of research for many years. However, the duration of SSRI-associated sexual adverse effects, and their possible persistence after treatment discontinuation, is still uncertain. The aims of the current systematic review were first to identify existing evidence of sexual dysfunction following SSRI discontinuation, and to provide an account of reported symptoms and proposed treatment options; and second, to establish whether current literature allows accurate estimates of the prevalence of such sexual dysfunction.

METHODS

A systematic review was conducted on PubMed, Embase, and Google Scholar; papers with clinical data regarding patients with persistent sexual dysfunction after SSRI treatment suspension were included.

RESULTS

Overall, two retrospective interventional studies, six observational studies and 11 case reports were judged eligible for inclusion. It was not possible to determine reliable estimates of prevalence. Similarly, a cause-effect relationship between SSRI exposure and persistent sexual impairment could not be ascertained. Nonetheless, the potential for continued sexual disturbances despite discontinuation could not be entirely ruled out.

CONCLUSIONS

There is a need to investigate a possible dose-response relationship between SSRI exposure and persistent sexual adverse effects. Treatment options for persistent dysfunctions remain limited, but novel therapeutic approaches may be required in order to address an otherwise neglected need for sexual well-being.

Neuropeptidergic control circuits in the spinal cord for male sexual behaviour: Oxytocin-gastrin-releasing peptide systems

The neuropeptidergic mechanisms controlling socio-sexual behaviours consist of complex neuronal circuitry systems in widely distributed areas of the brain and spinal cord. At the organismal level, it is now becoming clear that "hormonal regulations" play an important role, in addition to the activation of neuronal circuits. The gastrin-releasing peptide (GRP) system in the lumbosacral spinal cord is an important component of the neural circuits that control penile reflexes in rats, circuits that are commonly referred to as the "spinal ejaculation generator (SEG)." Oxytocin, long known as a neurohypophyseal hormone, is now known to be involved in the regulation of socio-sexual behaviors in mammals, ranging from social bonding to empathy. However, the functional interaction between the SEG neurons and the hypothalamo-spinal oxytocin system remains unclear. Oxytocin is known to be synthesised mainly in hypothalamic neurons and released from the posterior pituitary into the circulation. Oxytocin is also released from the dendrites of the neurons into the hypothalamus where they have important roles in social behaviours via non-synaptic volume transmission. Because the most familiar functions of oxytocin are to regulate female reproductive functions including parturition, milk ejection, and maternal behaviour, oxytocin is often thought of as a "feminine" hormone. However, there is evidence that a group of parvocellular oxytocin neurons project to the lower spinal cord and control male sexual function in rats. In this report, we review the functional interaction between the SEG neurons and the hypothalamo-spinal oxytocin system and effects of these neuropeptides on male sexual behaviour. Furthermore, we discuss the finding of a recently identified, localised "volume transmission" role of oxytocin in the spinal cord. Findings from our studies suggest that the newly discovered "oxytocin-mediated spinal control of male sexual function" may be useful in the treatment of erectile and ejaculatory dysfunction.

Estimating the risk of irreversible post-SSRI sexual dysfunction (PSSD) due to serotonergic antidepressants

BACKGROUND

Sexual dysfunction is a common side effect of Serotonergic antidepressants (SA) treatment, and persists in some patients despite drug discontinuation, a condition termed post-SSRI sexual dysfunction (PSSD). The risk for PSSD is unknown but is thought to be rare and difficult to assess. This study aims to estimate the risk of erectile dysfunction (ED) and PSSD in males treated with SAs.

METHODS

A 19-year retrospective cohort analysis was conducted using a computerized database of the largest HMO in Israel. ED was defined by phosphodiesterase-5 inhibitors prescriptions. 12,302 males aged 21-49 met the following criteria: non-smokers, no medical or psychiatric comorbidities or medications associated with ED, no alcohol or substance use. Logistic regression was used for estimation of ED risk in SA-treated subjects compared to non-SA-treated controls, assessed with and without the effects of age, body mass index (BMI), socioeconomic status (SES), depression and anxiety, yielding crude and adjusted odds ratios (cOR and aOR, respectively).

RESULTS

SAs were associated with an increased risk for ED (cOR = 3.6, p < 0.000001, 95% CI  2.8-4.8), which remained significant after adjusting for age, SES, BMI, depression and anxiety (aOR = 3.2, p < 0.000001, 95% CI  2.3-4.4). The risk for PSSD was 1 in 216 patients (0.46%) treated with SAs. The prevalence of PSSD was 4.3 per 100,000.

CONCLUSIONS

This work offers a first assessment of the small but significant risk of irreversible ED associated with the most commonly prescribed class of antidepressants which should enhance the process of receiving adequate informed consent for therapy.

[Antidepressant drugs-State of the art]

BACKGROUND

Due to their frequency, complications, and sequelae, depressive disorders are of great significance to patients, their environment, and society. They are considered the most frequent form of mental disturbances in old age. The use of antidepressant drugs (AD) represents a cornerstone of the treatment, which is always multidimensional.

OBJECTIVE

The classification, mechanism of action, efficacy and tolerability of AD are described. Furthermore, the practical treatment procedure as well as special aspects, such as treatment resistance and special features in old age are presented.

MATERIAL AND METHODS

Narrative review incorporating the most recent literature and the new edition of the national healthcare guidelines on unipolar depression.

RESULTS

In the past 20 years, a large number of so-called 2nd generation ADs have been approved worldwide with comparable efficacy but more favorable side effect profiles than conventional (tricyclic) substances. Almost all ADs act by enhancing monoaminergic, mostly serotonergic, neurotransmission. Other common features include a latency in the onset of action, moderate response rates, and potential efficacy on all core symptoms of depression. Side effects can include cardiovascular, metabolic, or sexual dysfunction, but these may significantly differ between drug classes. This enables individualized treatment taking age, individual risk factors, comorbidities and comedications into account.

CONCLUSION

With the correct interpretation of indications, knowledge of the risks, and consideration of the defined precautionary measures outlined here, treatment with AD is a safe and effective tool in the treatment of moderate and severe depression.

[Sexual dysfunction on the background of antidepressant therapy]

The review is devoted to the problem of sexual dysfunction caused by taking antidepressants. Sexual dysfunction is widespread, but it is not reported, and its impact on the quality of life and compliance of patients is underestimated. Partly because of its bidirectional association with depression, sexual dysfunction is difficult to diagnose. Possible mechanisms and risk factors associated with sexual dysfunction in patients with depression are considered. The data on the frequency of sexual dysfunction with the use of various antidepressants are given. Therapeutic strategies for sexual dysfunction associated with taking antidepressants are described. The advantages of agomelatin as an antidepressant associated with a low risk of sexual side effects are emphasized.

Paroxetine effects in adult male rat colon: Focus on gut steroidogenesis and microbiota

Paroxetine, a selective serotonin reuptake inhibitor (SSRI), is prescribed to treat psychiatric disorders, although an off-label SSRI use is also for functional gastrointestinal disorders. The mutual correlation between serotonin and peripheral sex steroids has been reported, however little attention to sex steroids synthesized by gut, has been given so far. Indeed, whether SSRIs, may also influence the gut steroid production, immediately after treatment and/or after suspension, is still unclear. The finding that gut possesses steroidogenic capability is of particular relevance, also for the existence of the gut-microbiota-brain axis, where gut microbiota represents a key orchestrator. On this basis, adult male rats were treated daily for two weeks with paroxetine or vehicle and, 24 h after treatment and at 1 month of withdrawal, steroid environment and gut microbiota were evaluated. Results obtained reveal that paroxetine significantly affects steroid levels, only in the colon but not in plasma. In particular, steroid modifications observed immediately after treatment are not overlap with those detected at withdrawal. Additionally, paroxetine treatment and its withdrawal impact gut microbiota populations differently. Altogether, these results suggest a biphasic effect of the drug treatment in the gut both on steroidogenesis and microbiota.

Cutting the First Turf to Heal Post-SSRI Sexual Dysfunction: A Male Retrospective Cohort Study

Post-SSRI sexual dysfunction (PSSD) is a set of heterogeneous sexual problems, which may arise during the administration of selective serotonin reuptake inhibitors (SSRIs) and persist after their discontinuation. PSSD is a rare clinical entity, and it is commonly associated with non-sexual concerns, including emotional and cognitive problems and poor quality of life. To date, however, no effective treatment is available. The aim of this study was to retrospectively evaluate the potential efficacy of the different treatments used in clinical practice in improving male PSSD. Of the 30 patients referred to our neurobehavioral outpatient clinic from January 2020 to December 2021, 13 Caucasian male patients (mean age 29.53 ± 4.57 years), previously treated with SSRIs, were included in the study. Patients with major depressive disorder and/or psychotic symptoms were excluded a priori to avoid overlapping symptomatology, and potentially reduce the misdiagnosis rate. To treat PSSD, we decided to use drugs positively affecting the brain dopamine/serotonin ratio, such as bupropion and vortioxetine, as well as other compounds. This latter drug is known not to cause or reverse iatrogenic SD. Most patients, after treatment with vortioxetine and/or nutraceuticals, reported a significant improvement in all International Index of Erectile Function-(IIEF-5) domains (p < 0.05) from baseline (T0) to 12-month follow-up (T1). Moreover, the only patient treated with pelvic muscle vibration reached very positive results. Although our data come from a retrospective open-label study with a small sample size, drugs positively modulating the central nervous system serotonin/dopamine ratio, such as vortioxetine, could be used to potentially improve PSSD. Large-sample prospective cohort studies and randomized clinical trials are needed to investigate the real prevalence of this clinical entity and confirm such a promising approach to a potentially debilitating illness.