Toward Personalized Sexual Medicine (Part 3): Testosterone Combined with a Serotonin1A Receptor Agonist Increases Sexual Satisfaction in Women with HSDD and FSAD, and Dysfunctional Activation of Sexual Inhibitory Mechanisms

Interplay between sexual excitation and inhibition: impact on sexual function and neural correlates of erotic stimulus processing in women

Background

As outlined by the dual control model (DCM), individual differences in the regulation of sexual arousal following sexual stimulation depend on two distinct neurophysiological processes: sexual excitation (SE) and sexual inhibition (SI). Although associations with sexual function, behavior, and cue processing have been demonstrated in previous research, underlying neural correlates remain insufficiently explored. Moreover, interactive effects of SE/SI as proposed by the DCM, as well as factors impacting SE/SI properties, such as the use of oral contraceptives (OCs), have not received adequate attention in existing research.

Methods

90 healthy, sexually active women (n = 51 using OCs, n = 39 naturally cycling) completed an Emotional-Picture-Stroop-Paradigm (EPSP) while a 64-channel EEG was recorded. LPP amplitudes toward erotic and neutral stimuli were consecutively computed as a marker of motivational salience and approach motivation. Additionally, women provided self-reports of SE/SI and sexual function. Moderation analyses were performed to assess interactive effects of SE/SI in predicting LPP amplitudes and sexual function.

Results

Sexual function was negatively associated with SI levels but unrelated to SE. Higher SI was associated with reduced LPP amplitudes in response to erotic stimuli. This negative association was, however, attenuated for women high in SE, suggesting interactive effects of SE/SI. Furthermore, women using OCs reported lower SE compared to naturally cycling women.

Conclusion

The observed findings provide additional psychophysiological evidence supporting the DCM and underscore the relevance of interactive SE/SI effects in stimulus processing and approach motivation. They also highlight the possible impact of OCs on psychosexual variables that warrants further research.

The Dual Control Model of Sexual Response: A Scoping Review, 2009-2022

The Dual Control Model proposes that sexual arousal and related processes are dependent on the balance between sexual excitation and sexual inhibition, and that individuals vary in their propensity for these processes. This scoping review provides an overview and discussion of the questionnaires used to measure the propensities for sexual excitation and inhibition, their translation and validation in other languages, and their application in empirical research on topics ranging from sexual desire and arousal, sexual (dys)function, sexual risk taking, asexuality, hypersexuality, and sexual aggression. A total of 152 papers, published between 2009 and 2022 and identified using online databases, were included in this review. The findings, consistent with those reviewed by Bancroft et al. (2009), suggest that sexual excitation is particularly relevant to sexual desire and responsivity and predictive of asexuality and hypersexuality. Sexual inhibition plays a role in sexual dysfunction. sexual risk taking, and sexual aggression, although often in interaction with sexual excitation. Suggestions for the further development of the model and for future studies are discussed.

Menopause and female sexual dysfunctions (FSDs)

Biological and psycho-relational factors contribute equally to the development of sexual symptoms and associated distress, a key element to diagnose female sexual dysfunctions (FSDs) in menopausal women. Consultation at midlife represents an optimal time to discuss sexual life, and healthcare providers (HCPs) have to be proactive in rising the conversation, as patients may not report their sexual concerns spontaneously. An accurate sexual history is essential to characterize the primary symptom, determine the impact on patient's quality of life and identify risk and precipitating factors. Among FSDs, hypoactive sexual desire disorder (HSDD) is very frequent at midlife together with genitourinary syndrome of menopause (GSM), a chronic condition negatively affecting the full sexual response. A multidimensional approach targeted to the patient's characteristics, goals and expectations is mandatory and should start from educative counselling and correction of modifiable risk factors. When specific treatments are required, they should include non-pharmacological and pharmacological options, often prescribed in combination to address concomitantly the biological and psychosocial components of FSDs.

Hypoactive Sexual Desire Disorder in Women: Physiology, Assessment, Diagnosis, and Treatment

Nearly half of women in the United States report problems with sexual function. Many health care providers do not ask about sexual concerns during routine clinical encounters because of personal discomfort, lack of familiarity with treatment, or the belief that they lack adequate time to address this complex issue. This may be especially true for hypoactive sexual desire disorder (HSDD), the most commonly identified sexual problem among women. HSDD is characterized by a deficiency of sexual thoughts, feelings, or receptiveness to sexual stimulation that has been present for at least 6 months, causes personal distress, and is not due to another medical condition. This is an up-to-date overview of HSDD for clinicians, discussing its physiology, assessment, diagnosis, and treatment strategies. Although a definitive physiology of HSDD is still unknown, multiple hormones and neurotransmitters likely participate in a dual-control model to balance excitation and inhibition of sexual desire. For assessment and diagnosis, validated screening tools are discussed, and the importance of a biopsychosocial assessment is emphasized, with guidance on how this can be implemented in clinical encounters. The 2 recently approved medications for HSDD, flibanserin and bremelanotide, are reviewed as well as off-label treatments. Overall, HSDD represents a common yet likely underrecognized disorder that midwives and other health care providers who care for women across the life span are in a unique position to address.

A Systematic Literature Review of Health-related Quality of Life Measures for Women with Hypoactive Sexual Desire Disorder and Female Sexual Interest/Arousal Disorder

INTRODUCTION

Hypoactive Sexual Desire Disorder (HSDD) / Female Sexual Interest/Arousal Disorder (FSIAD) impacts health-related quality of life (HRQoL) of women and their partners, yet existing measures fail to adequately capture relevant concepts (ie, what is essential to measure including symptoms/impacts) important to women with HSDD/FSIAD.

OBJECTIVES

To identify HRQoL tools used to assess women with HSDD/FSIAD, and to evaluate their psychometric properties (ie, reliability, validity, and responsiveness).

METHODS

We conducted searches in PubMed, Embase and PsychINFO from June 5, 1989 to September 30, 2020 for studies in women with HSDD/FSIAD and psychometric analyses (English only). Principles of the Preferred Reporting Items for Systematic reviews and Meta-Analyses, the COnsensus-based Standards for the selection of health Measurement INstruments Risk of Bias Checklist and other psychometric criteria were applied. Based on this search, 56 papers were evaluated including 15 randomized-controlled trials, 11 observational/single arm/open label studies, and 30 psychometric studies.

RESULTS

Of the 18 measures identified, the Female Sexual Function Index (FSFI) and Female Sexual Distress Scale-Revised (FSDS-R) were included in most studies (> 50%). General HRQoL instruments were not used in any of the clinical trials; the SF-12, SF-36 and EQ-5D-5L were reported in two observational studies. No instruments achieved positive quality ratings across all psychometric criteria. The FSFI, FSDS-R, Sexual Event Diary (SED) and the Sexual Desire Relationship Distress Scale (SDRDS), were the only measures to receive a positive rating for content validity.

CONCLUSION

Reliable and valid HRQoL measures that include sexual desire and distress are needed to provide a more systematic and comprehensive assessment of HRQoL and treatment benefits in women with HSDD/FSIAD. While inferences about HRQoL are limited due to the lack of uniformity in concepts assessed and limited psychometric evaluation of these measures in women with HSDD/FSIAD, opportunities exist for the development of reliable and validated tools that comprehensively measure the most relevant and important concepts in women with HSDD/FSIAD. Lim-Watson MZ, Hays RD, Kingsberg S, et al. A systematic literature review of health-related quality of life measures for women with Hypoactive Sexual Desire Disorder and Female Sexual Interest/Arousal Disorder. Sex Med Rev 2021;XX:XXX-XXX.

Management of hypoactive sexual desire disorder in transgender women: a guide for clinicians

Hypoactive sexual desire disorder (HSDD) represents a common condition among transgender women. However, to date no specific guidelines for the management of HSDD in transgender persons are available. The aim of the present narrative Review is to evaluate evidence-based treatment for HSDD and to suggest treatment options for HSDD in transgender women. Clinically relevant publications on the management of HSDD (from 1985 to 2020) were searched in PubMed and Medline databases, using the following terms: "sexual desire", "sexual health", "HSDD", "transgender", "gender-affirming treatment", "sexual therapy", "testosterone treatment", "Central nervous system-active medications", and variants. Since sexual desire could be affected by several factors, a comprehensive assessment of HSDD- exploring biological, psychological, and social domains- is recommended, in order to identify possible predisposing, precipitating and maintaining factors. Among treatment options, transgender women may benefit of different sex therapy strategies and/or central nervous system-active medications-such as flibanserin, bremelanotide, bupropion and buspirone-and transdermal testosterone, bearing in mind that this option could be poorly accepted by patients due to the risk of virilizing effects. The lack of data regarding the efficacy of HSDD treatment options in transgender women emphasize the need for literature to focus more on this topic in the future.

Female Hypoactive Sexual Desire Disorder: A Practical Guide to Causes, Clinical Diagnosis, and Treatment

Hypoactive sexual desire disorder (HSDD) in women is defined as the persistent or recurrent absence of sexual thoughts or fantasies and/or lack of desire for sexual activity that is associated with marked personal distress and/or interpersonal difficulties, and cannot be better attributed to another primary disorder, medication, or general medical condition. Notably, HSDD shares some similarity with depression, as its etiology can be explained using a biopsychosocial model that includes biological, psychological, and sociocultural factors, as well as interpersonal influences. Due to its high prevalence and negative impact on the overall health and well-being of women, primary care health professionals and women's health practitioners need to be actively aware of HSDD, particularly because patients may be reluctant or unwilling to initiate a discussion about their sexual concerns during routine visits. HSDD is well established as a valid and treatable clinical entity. Even for those inexperienced in treating sexual problems, there are simple and validated screening tools such as the Decreased Sexual Desire Screener that can help identify HSDD and a need for further evaluation and treatment. There have been few established pharmacologic treatments for HSDD. Flibanserin was the first drug approved for the treatment of HSDD by the U.S. Food and Drug Administration (FDA). Bremelanotide, a novel melanocortin receptor agonist, was recently approved by the FDA for the treatment of acquired, generalized HSDD in premenopausal women. Increased awareness and recognition of HSDD as a medical condition should provide an incentive for further clinical development of effective treatments for HSDD.

Testosterone therapy and other treatment modalities for female sexual dysfunction

PURPOSE OF REVIEW

Recently in October 2019 a Global Consensus Position on the use of Testosterone Therapy for Women was published. The use of testosterone and other agents for female sexual dysfunction (FSD) is an important topic for the urologist focusing on sexual health. This review describes the known causes for FSD, and discusses the role of androgens in this disorder, the evidence for using testosterone treatment, and other current and emerging therapies.

RECENT FINDINGS

A recent meta-analysis, published in The Lancet Diabetes & Endocrinology evaluated a total of 36 randomized control trials spanning 1990-2018 and includes a total of 8480 patients. The primary findings were that testosterone therapy (TTh) increased sexual function including satisfactory sexual event frequency, sexual desire, pleasure, arousal, orgasm, responsiveness, and self-image when compared with either a placebo or drug-control (e.g., estrogen ± progestogen). In addition, TTh reduced sexual concerns and distress in postmenopausal women. Side effects included an increase in weight, acne, and hair growth, but there was no increase in serious adverse events. Importantly, TTh duration was greater than 12 weeks in all randomized control trials included in this meta-analysis.

SUMMARY

TTh is effective to treat FSD in postmenopausal women. More data is required to evaluate the long-term safety data on the effects of TTh on cardiovascular health, breast health, cognitive function, and the musculoskeletal system in women.

Understanding sexual arousal and subjective-genital arousal desynchrony in women

Sexual arousal in women comprises two components: genital arousal and subjective arousal. Genital arousal is characterized by genital vasocongestion and other physiological changes that occur in response to sexual stimuli, whereas subjective arousal refers to mental engagement during sexual activity. For some women, genital arousal enhances subjective arousal; for others, the two types of arousal are desynchronous. However, the relationship between genital and subjective arousal might not be relevant to the diagnosis and treatment of sexual arousal dysfunction. Studies have shown that not all women who report sexual arousal problems have decreased genital arousal, and only some women with decreased genital arousal have low subjective arousal. To develop efficacious treatments for female sexual arousal dysfunction, researchers need to differentiate the women for whom genital sensations have a critical role in their subjective arousal from those who are not mentally aroused by genital cues. The mechanisms by which women become aroused and the inputs into arousal have considerable implications for treatment outcomes.

Genotype scores predict drug efficacy in subtypes of female sexual interest/arousal disorder: A double-blind, randomized, placebo-controlled cross-over trial

Attempts to develop a drug treatment for female sexual interest/arousal disorder have so far been guided by the principle of ‘one size fits all’, and have failed to acknowledge the complexity of female sexuality. Guided by personalized medicine, we designed two on-demand drugs targeting two distinct hypothesized causal mechanisms for this sexual disorder. The objective of this study was to design and test a novel procedure, based on genotyping, that predicts which of the two on-demand drugs will yield a positive treatment response. In a double-blind, randomized, placebo-controlled cross-over experiment, 139 women with female sexual interest/arousal disorder received three different on-demand drug-combination treatments during three 2-week periods: testosterone 0.5 mg + sildenafil 50 mg, testosterone 0.5 mg + buspirone 10 mg, and matching placebo. The primary endpoint was change in satisfactory sexual events. Subjects’ genetic profile was assessed using a microarray chip that measures 300,000 single-nucleotide polymorphisms. A preselection of single-nucleotide polymorphisms associated with genes that are shown to be involved in sexual behaviour were combined into a Phenotype Prediction Score. The Phenotype Prediction Score demarcation formula was developed and subsequently validated on separate data sets. Prediction of drug-responders with the Phenotype Prediction Score demarcation formula gave large effect sizes (d = 0.66 through 1.06) in the true drug-responders, and medium effect sizes (d = 0.51 and d = 0.47) in all patients (including identified double, and non-responders). Accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of the Phenotype Prediction Score demarcation formula were all between 0.78 and 0.79, and thus sufficient. The resulting Phenotype Prediction Score was validated and shown to effectively and reliably predict which women would benefit from which on-demand drug, and could therefore also be useful in clinical practice, as a companion diagnostic establishing the way to a true personalized medicine approach.

Evaluation and Management of Hypoactive Sexual Desire Disorder

INTRODUCTION

Hypoactive sexual desire disorder (HSDD) often has a negative impact on the health and quality of life of women; however, many women do not mention-let alone discuss-this issue with their physicians. Providers of gynecologic services have the opportunity to address this subject with their patients.

AIM

To review the diagnosis and evidence-based treatment of low sexual desire in women with a focus on strategies that can be used efficiently and effectively in the clinic.

METHODS

The Medline database was searched for clinically relevant publications on the diagnosis and management of HSDD.

RESULTS

HSDD screening can be accomplished during an office visit with a few brief questions to determine whether further evaluation is warranted. Because women's sexual desire encompasses biological, psychological, social, and contextual components, a biopsychosocial approach to evaluating and treating patients with HSDD is recommended. Although individualized treatment plan development for patients requires independent medical judgment, a simple algorithm can assist in the screening, diagnosis, and management of HSDD. Once a diagnosis of HSDD has been made, interventions can begin with office-based counseling and progress to psychotherapy and/or pharmacotherapy. Flibanserin, a postsynaptic 5-hydroxytryptamine 1A agonist and 2A antagonist that decreases serotonin levels and increases dopamine and norepinephrine levels, is indicated for acquired, generalized HSDD in premenopausal women and is the only agent approved in the United States for the treatment of HSDD in women. Other strategies to treat HSDD include using medications indicated for other conditions (eg, transdermal testosterone, bupropion). Bremelanotide, a melanocortin receptor agonist, is in late-stage clinical development.

CONCLUSIONS

Providers of gynecologic care are uniquely positioned to screen, counsel, and refer patients with HSDD. Options for pharmacotherapy of HSDD are currently limited to flibanserin, approved by the US Food and Drug Administration, and off-label use of other agents. Clayton AH, Kingsberg SA, Goldstein I. Evaluation and Management of Hypoactive Sexual Desire Disorder. Sex Med 2018;6:59-74.

An International Urogynecological Association (IUGA)/International Continence Society (ICS) joint report on the terminology for the assessment of sexual health of women with pelvic floor dysfunction

AIMS

The terminology in current use for sexual function and dysfunction in women with pelvic floor disorders lacks uniformity, which leads to uncertainty, confusion, and unintended ambiguity. The terminology for the sexual health of women with pelvic floor dysfunction needs to be collated in a clinically-based consensus report.

METHODS

This report combines the input of members of the Standardization and Terminology Committees of two International Organizations, the International Urogynecological Association (IUGA), and the International Continence Society (ICS), assisted at intervals by many external referees. Internal and external review was developed to exhaustively examine each definition, with decision-making by collective opinion (consensus). Importantly, this report is not meant to replace, but rather complement current terminology used in other fields for female sexual health and to clarify terms specific to women with pelvic floor dysfunction.

RESULTS

A clinically based terminology report for sexual health in women with pelvic floor dysfunction encompassing over 100 separate definitions, has been developed. Key aims have been to make the terminology interpretable by practitioners, trainees, and researchers in female pelvic floor dysfunction. Interval review (5-10 years) is anticipated to keep the document updated and as widely acceptable as possible.

CONCLUSION

A consensus-based terminology report for female sexual health in women with pelvic floor dysfunction has been produced aimed at being a significant aid to clinical practice and a stimulus for research.

Recent Developments in Psychopharmaceutical Approaches to Treating Female Sexual Interest and Arousal Disorder

Purpose of Review

This review summarizes the recent literature and empirical studies on psychopharmacological approaches to treating female sexual interest/arousal disorder (FSIAD).

Recent Findings

Several new drugs for FSIAD that are intended to increase sexual responsiveness by influencing central excitatory and inhibitory neuromodulatory processes are under development. Studies on flibanserin resulted in the first approved medication for the treatment of low sexual desire in premenopausal women. New drugs under development are testosterone combined with sildenafil or buspiron, bremelanotide, BP101, and nasal testosterone (TBS-2).

Summary

Although pharmacological enhancement of sexual responsiveness may be potentially helpful in the treatment of FSIAD, the observed effects of flibanserin and other new drugs under development seem limited in terms of clinical significance. Given the multifactorial character of FSIAD, it may be important to integrate psychopharmacological treatment with sex therapy for optimal treatment efficacy.

Flibanserin for hypoactive sexual desire disorder: place in therapy

The pathophysiology, diagnosis and treatment of female sexual interest in pre- and post-menopausal women present a complex arena for patients and physicians to navigate. Flibanserin was the first pharmacologic treatment, approved by the United States Food and Drug Administration in August 2015, for hypoactive sexual desire disorder (HSDD) in premenopausal women. Side effects, contraindications and lack of approval in postmenopausal women are all limitations, as are issues surrounding patient and physician knowledge and access. Testosterone, buspirone, sildenafil, bupropion, bremelanotide, as well as herbal medications (Herbal vX or Tribulus terrestris) have demonstrated some clinical benefit in women with sexual dysfunction disorders however, trials have significant design, dosing or generalizability limitations. Nonpharmaceutical cognitive behavioral therapy, mindfulness meditation, pelvic floor therapy, and clitoral stimulators are also interventions women may pursue. This manuscript will explore the clinical data regarding these therapeutic modalities so as to bring attention to this issue of female HSDD, to offer an overview of current research, and to incite providers to initiate discussion among themselves and their patients.

Controversies of Women’s Sexual Arousal and Desire

Abstract. The past three decades have seen an unprecedented increase in empirical research on women’s sexual response. In this review, we critically examine current controversies and assumptions associated with the nature of women’s sexual arousal and desire. We focus specifically on four assumptions: (1) the assumption that women should be aroused by stimuli that align with their stated preferences, (2) the assumption that women’s physiological and self-reported arousal should perfectly align, (3) the assumption that sexual desire precedes sexual arousal, and (4) the assumption that a single pharmaceutical compound will adequately restore women’s sexual response to her level of satisfaction. Engaging a gendered psychological framework for conceptualizing women’s sexuality, we emphasize the need for models of women’s sexual response to be sensitive to the sexed biological processes and gendered psychosocial factors that contribute to a woman’s unique sexual experience.

Single dose sublingual testosterone and oral sildenafil vs. a dual route/dual release fixed dose combination tablet: a pharmacokinetic comparison

AIM

The aim was to compare the pharmacokinetic profiles of two formulations of a combination drug product containing 0.5 mg testosterone and 50 mg sildenafil for female sexual interest/arousal disorder. The prototype (formulation 1) consists of a testosterone solution for sublingual administration and a sildenafil tablet that is administered 2.5 h later. The dual route/dual release fixed dose combination tablet (formulation 2) employs a sublingual and an oral route for systemic uptake. This tablet has an inner core of sildenafil with a polymeric time delay coating and an outer polymeric coating containing testosterone. It was designed to increase dosing practicality and decrease potential temporal non-adherence through circumventing the relatively complex temporal dosing scheme.

METHODS

Twelve healthy premenopausal subjects received both formulations randomly on separate days. Blood was sampled frequently to determine the pharmacokinetics of free testosterone, total testosterone, dihydrotestosterone, sildenafil and N-desmethyl-sildenafil.

RESULTS

Formulation 2 had a higher maximum concentration (Cmax ) for testosterone, 8.06 ng ml(-1) (95% confidence interval [CI] 6.84, 9.28) and higher area under the plasma concentration-time curve (AUC), 7.69 ng ml(-1)  h (95% CI 6.22, 9.16) than formulation 1, 5.66 ng ml(-1) (95% CI 4.63, 6.69) and 5.12 ng ml(-1)  h (95% CI 4.51, 5.73), respectively. Formulation 2 had a lower Cmax for sildenafil, 173 ng ml(-1) (95% CI 126, 220) and a lower AUC, 476 ng ml(-1)  h (95% CI 401, 551) than formulation 1, 268 ng ml(-1) (95% CI 188, 348) and 577 ng ml(-1)  h (95% CI 462, 692), respectively. Formulation 2 released sildenafil after 2.75 h (95% CI 2.40, 3.10).

CONCLUSIONS

The dual route/dual release fixed dose combination tablet fulfilled its design criteria and is considered suitable for further clinical testing.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

Female sexual interest/arousal disorder (FSIAD) is a significant problem impacting psychological well-being, but the pharmacotherapeutic options for this problem are lacking. The combined, on-demand, sublingual administration of low dose sublingual testosterone and oral administration of sildenafil is a novel pharmacotherapeutic option under development for FSIAD. In proof-of-concept trials, these compounds were successfully administered via different dosage forms (sublingual and oral) at different time points (separated by 2.5 h) because of their markedly different pharmacokinetic-pharmacodynamic profiles. For future larger scale studies and the clinical practice, this raises obvious adherence issues.

WHAT THIS STUDY ADDS

A newly developed dual route/dual release fixed dose combination tablet containing testosterone and sildenafil mimics the pharmacokinetic profile of these components when they are administered as different dosage forms, 2.5 h apart. This combination tablet is a suitable final pharmaceutical drug product that will be used in future studies.

The Female Sexual Response: Current Models, Neurobiological Underpinnings and Agents Currently Approved or Under Investigation for the Treatment of Hypoactive Sexual Desire Disorder

How a woman responds to sexual cues is highly dependent on a number of distinct, yet related, factors. Researchers have attempted to explain the female sexual response for decades, but no single model reigns supreme. Proper female sexual function relies on the interplay of somatic, psychosocial and neurobiological factors; misregulation of any of these components could result in sexual dysfunction. The most common sexual dysfunction disorder is hypoactive sexual desire disorder (HSDD). HSDD is a disorder affecting women across the world; a recent in-person diagnostic interview study conducted in the USA found that an estimated 7.4% of US women suffer from HSDD. Despite the disorder's prevalence, it is often overlooked as a formal diagnosis. In a survey of primary care physicians and obstetrics/gynaecology specialists, the number one reason for not assigning an HSDD diagnosis was the lack of a safe and effective therapy approved by the US Food and Drug Administration (FDA). This changed with the recent FDA approval of flibanserin (Addyi™) for the treatment of premenopausal women with acquired, generalized HSDD; there are still, however, no treatments approved outside the USA. HSDD is characterized by a marked decrease in sexual desire, an absence of motivation (also known as avolition) to engage in sexual activity, and the condition's hallmark symptom, marked patient distress. Research suggests that HSDD may arise from an imbalance of the excitatory and inhibitory neurobiological pathways that regulate the mammalian sexual response; top-down inhibition from the prefrontal cortex may be hyperactive, and/or bottom-up excitation to the limbic system may be hypoactive. Key neuromodulators for the excitatory pathways include norepinephrine, oxytocin, dopamine and melanocortins. Serotonin, opioids and endocannabinoids serve as key neuromodulators for the inhibitory pathways. Evolving treatment strategies have relied heavily on these crucial research findings, as many of the agents currently being investigated as treatment options for HSDD target and influence key players within these excitatory and inhibitory pathways, including various hormone therapies and centrally acting drugs, such as buspirone, bupropion and bremelanotide.

Psychiatric disorders and sexual dysfunction

Sexual problems are highly prevalent among patients with psychiatric disorders. They may be caused by the psychopathology of the psychiatric disorder but also by its pharmacotherapy. Both positive symptoms (e.g., psychosis, hallucinations) as well as negative symptoms (e.g., anhedonia) of schizophrenia may negatively interfere with interpersonal and sexual relationships. Atypical antipsychotics have fewer sexual side-effects than the classic antipsychotics. Mood disorders may affect libido, sexual arousal, orgasm, and erectile function. With the exception of bupropion, agomelatine, mirtazapine, vortioxetine, amineptine, and moclobemide, all antidepressants cause sexual side-effects. Selective serotonin reuptake inhibitors (SSRIs) may particularly delay ejaculation and female orgasm, but also can cause decreased libido and erectile difficulties. SSRI-induced sexual side-effects are dose-dependent and reversible. Very rarely, their sexual side-effects persist after SSRI discontinuation. This is often preceded by genital anesthesia. Some personality characteristics are a risk factor for sexual dysfunction. Also patients with eating disorders may suffer from sexual difficulties. So far, research into psychotropic-induced sexual side-effects suffers from substantial methodologic limitations. Patients tend not to talk with their clinician about their sexual life. Psychiatrists and other doctors need to take the initiative to talk about the patient's sexual life in order to become informed about potential medication-induced sexual difficulties.

Pharmacokinetics of a prototype formulation of sublingual testosterone and a buspirone tablet, versus an advanced combination tablet of testosterone and buspirone in healthy premenopausal women

The study aimed to compare the kinetics of two novel combination drug products for Female Sexual Interest/Arousal Disorder (FSIAD). Thirteen women received testosterone via the sublingual route followed 2.5 hours later by a buspirone tablet, versus a single combination tablet swallowed at once. The first clinical prototype consisted of a sublingual solution containing testosterone (0.5 mg) complexed with cyclodextrin and a tablet containing 10 mg buspirone, in a gelatin capsule to ensure blinding during the clinical studies. The innovative fixed-combination tablet consists of an inner-core component of 10 mg buspirone coated with a polymeric time-delay coating and an outer polymeric coating containing testosterone with hydroxypropyl-beta cyclodextrin. We observed an immediate testosterone pulse absorption from both formulations. We also demonstrated that there was adequate absorption of buspirone (>80 % relative to the conventional tablet) and a time delay in release of buspirone of 3.3 hours, close to the 3.0 hours of the reference formulation that showed clinical efficacy in early proof-of-principle studies. The newly developed combination tablet fulfils its design criteria and is a convenient tablet for further clinical studies in FSIAD.

Efficacy of testosterone combined with a PDE5 inhibitor and testosterone combined with a serotonin (1A) receptor agonist in women with SSRI-induced sexual dysfunction. A preliminary study

Selective serotonin reuptake inhibitors (SSRIs) are known to cause sexual dysfunction, such as decreased sexual motivation, desire, arousal, and orgasm difficulties. These SSRI-induced sexual complaints have a high prevalence rate, while there is no approved pharmacological treatment for SSRI-induced sexual dysfunction. It is hypothesized that a polymorphisms in the androgen receptor gene, encoded by the nucleotides cysteine, adenine, and guanine (CAG), influence the effect of testosterone on sexual functioning. In an explorative, randomized, double-blind, placebo-controlled, crossover study we investigated the possible effects of sublingual testosterone combined with a serotonin (5-HT)1A receptor agonist, and of sublingual testosterone combined with a phosphodiesterase type 5 inhibitor (PDE5-i) on sexual functioning in women with SSRI-induced sexual dysfunction. Furthermore, we did an exploratory analysis to assess if the CAG polymorphism influences this effect. 21 pre- and postmenopausal women with SSRI-induced sexual dysfunction participated and underwent the following interventions: a combination of testosterone (0.5 mg) sublingually and the PDE5-i sildenafil (50 mg) and a combination of testosterone (0.5 mg) sublingually and the 5-HT1A receptor agonist buspirone (10 mg). The results show that women who use a low dose of SSRI and have relatively long CAG repeats report a marked improvement in sexual function in response to both treatments compared to placebo. This explorative study and preliminary results indicate that in women with SSRI-induced sexual dysfunction, a combination of testosterone sublingually and a PDE5-i or testosterone sublingually and a 5-HT1A receptor agonist might be promising treatments for certain subgroups of women with this condition.

Testosterone levels and sexual function disorders in depressive female patients: effects of antidepressant treatment

INTRODUCTION

Women suffer from depression more frequently than men, which indicates that sex hormones might be involved in the etiology of this disease.

AIMS

The purpose of this study was to assess the relationship between testosterone and depression pathophysiology in depressive women along with sexual function. We also investigated whether antidepressant treatment causes any change in levels of this hormone or in sexual function.

METHODS

Premenopausal female patients aged 25-46 years (n = 52) with diagnosed major depression were included in this study as the patient group, and 25- to 46-year-old premenopausal women without depression (n = 30) were included as the control group.

MAIN OUTCOME MEASURES

Serum testosterone and sex hormone-binding globulin (SHBG) levels were measured twice, before and after the antidepressant treatment. Bioavailable testosterone (cBT) levels were calculated using the assay results for total testosterone (TT), SHBG, and albumin according to the formulas of Vermeulen et al. Depression severity was measured using the 17-item Hamilton Depression Rating Scale, and sexual function was evaluated with the Arizona Sexual Experience Scale.

RESULTS

The mean TT and cBT levels significantly increased in the patient group after the antidepressant treatment (P < 0.001). Pre-treatment TT and cBT levels were significantly lower in the patient group than in the control group (P < 0.001). Similar results were obtained for post-treatment serum TT and cBT levels in the patient and control groups (P > 0.05). There were no significant differences among the groups in terms of SHBG level.

CONCLUSION

The low testosterone levels in depressed women compared with women in the control group and the elevated levels post-pharmacotherapy suggest that testosterone may be involved in depression.