Treatment options for erectile dysfunction

Prostaglandins as a Topical Therapy for Erectile Dysfunction: A Comprehensive Review

INTRODUCTION

Erectile dysfunction (ED) is a substantial cause of dissatisfaction among many men. This discontentment has led to the emergence of various drug treatment options for this problem.

OBJECTIVES

Unfortunately, due to various interactions, contraindications, and side effects, systemic therapies such as phosphodiesterase-5 inhibitors (including sildenafil, tadalafil, vardenafil, avanafil, etc.) are not welcomed in many patients. These problems have led researchers to look for other ways to reduce these complications.

METHODS

This article holistically reviews the efficacy of topical prostaglandins and their role in treating ED. We sought to provide a comprehensive overview of recent findings on the current topic by using the extensive literature search to identify the latest scientific reports on the topic.

RESULTS

In this regard, topical and transdermal treatments can be suitable alternatives. In diverse studies, prostaglandins, remarkably PGE1 (also known as alprostadil), have been suggested to be an acceptable candidate for topical treatment.

CONCLUSION

Numerous formulations of PGE1 have been used to treat patients so far. Still, in general, with the evolution of classical formulation methods toward modern techniques (such as using nanocarriers and skin permeability enhancers), the probability of treatment success also increases.

Current Techniques for the Objective Measures of Erectile Hardness

INTRODUCTION

One of the most discussed topics in the urology provider's office is that of the male penile erection. Moreover, this is also a frequent basis for consultation by primary care practitioners. As such, it is essential that urologists are familiar with the various means by which the male erection may be evaluated.

OBJECTIVES

This article describes several techniques presently available that may serve to objectively quantify the rigidity and hardness of the male erection. These techniques are meant to bolster information gathered from the patient interview and physical examination to better guide patient management.

METHODS

An extensive literature review was performed examining publications in PubMed on this subject, including corresponding contextual literature.

RESULTS

While validated patient questionnaires have been routinely employed, the urologist has many additional means available to uncover the extent of the patient's pathology. Many of these tools are noninvasive techniques that involve virtually no risk to the patient and take advantage of pre-existing physiologic properties of the phallus and its blood supply to estimate corresponding tissue stiffness. Specifically, Virtual Touch Tissue Quantification which precisely quantifies axial and radial rigidity, can provide continuous data on how these forces change over time, thus providing a promising comprehensive assessment.

CONCLUSION

Quantification of the erection allows for the patient and provider to assess response to therapy, aids the surgeon in choice of appropriate procedure, and guides effective patient counseling regarding expectation management. Rohrer GE, Premo H, Lentz AC. Current Techniques for the Objective Measures of Erectile Hardness. Sex Med Rev 2022;XX:XXX-XXX.

Sexual Dysfunction Among Patients With Chronic Kidney Disease

Sexual dysfunction (SD) in patients with chronic kidney disease is common and negatively impacts quality of life. SD is often under-appreciated because of overall low awareness. Diagnosis of SD is subjective, and manifestations can be different among men and women. Causes of SD are multifactorial, including psychological disorders, hormonal imbalances, vascular disorders, neurological disorders, and medication side effects. Non-specific approaches to improving sexual function include addressing underlying psychological disorders, promoting lifestyle modifications, optimizing dialysis care, and facilitating successful kidney transplantation, whereas treatment with phosphodiesterase type 5 inhibitor, hormone replacement, and mechanical devices can be offered to patients with specific indications.

Effect of Intracavernosal Injection of Prostaglandin E1 on Duration and Rigidity of Erection in Patients With Vasculogenic Erectile Dysfunction: Is It Dose Dependent?

OBJECTIVE

To assess if the effect of intracavernosal injection of prostaglandin E1 (PGE1) on duration and rigidity of erection is dose dependent in patients with different types of vasculogenic erectile dysfunction (ED)?

METHODS

A hundred patients with ED were assigned into 4 groups (n = 25/each); group (A) patients with arteriogenic ED, group (B) patients with veno-occlusive ED, group (C) patients with mixed (arteriogenic and veno-occlusive) ED, and group (D) patients who have only psychogenic ED (control). After intracavernosal injection of PGE1, patients were assessed using penile Doppler ultrasonography and erection hardness score together with calculation of erection duration. The starting dose of PGE1 was 5 μg which was increased to 10 µg and 20 µg as a maximal dose when needed.

RESULTS

The mean PSV of patients in groups A, B, C, and D were 24.38 ± 3.3, 37.74 ± 8.28, 22.24 ± 3.85, and 47.76 ± 6.27, respectively. In group D, 88% have achieved the best response at dose of 5 µg while 5.3%, 21.7%, and 0% have achieved the best response at dose of 5 µg in groups A, B, and C, respectively (P < .05 for each). The rest of patients have required either 10 or 20µg to achieve the best response. Patients in group C have required the highest dose of PGE1 to achieve the best response (P < .05).

CONCLUSION

Intracavernosal injection of PGE1 in escalating doses have improved the rigidity and duration of erection in patients with different types of vasculogenic ED. Patients with mixed arteriogenic and veno-occlusive ED have required the highest dose of PGE1 to achieve the best response.

Ionic Channels as Potential Therapeutic Targets for Erectile Dysfunction: A Review

Erectile dysfunction (ED) is a prevalent condition, especially in men over 40 years old, characterized by the inability to obtain and/or maintain penile erection sufficient for satisfactory sexual intercourse. Several psychological and/or organic factors are involved in the etiopathogenesis of ED. In this context, we gathered evidence of the involvement of Large-conductance, Ca2+-activated K+ channels (BKCa), Small-conductance, Ca2+-activated K+ channels (SKCa), KCNQ-encoded voltage-dependent K+ channels (KV7), Transient Receptor Potential channels (TRP), and Calcium-activated Chloride channels (CaCC) dysfunctions on ED. In addition, the use of modulating agents of these channels are involved in relaxation of the cavernous smooth muscle cell and, consequent penile erection, suggesting that these channels are promising therapeutic targets for the treatment of erectile dysfunction.

Role of application of tadalafil 5 mg once-daily (≥6 months) in men with erectile dysfunction from six randomized controlled trials

This meta-analysis was performed to assess the efficacy and safety of taking tadalafil 5 mg once-daily for at least 6 months in the treatment of erectile dysfunction (ED). Based on databases: MEDLINE, EMBASE and Cochrane Controlled Trials Register, this analysis was performed to collect randomized controlled trials (RCTs) of tadalafil 5mg once-daily in treating ED over 6 months. Reviewers also investigated the references of each literature. The meta-analysis covered a total of 1,596 patients in six RCTs. The tadalafil group performed a better effect in terms of the international index of erectile function-erectile function (IIEF) domain (P=0.005) for the treatment of ED compared with the placebo group. Safety assessments including discontinuations due to adverse events (AEs) (P=0.31) and treatment-emergent AEs (P=0.06) indicated that the tadalafil group had a better tolerate. The analysis elucidates that the dose of 5 mg per day of tadalafil showed a good effect after the treatment of at least 6 months relative to the control group with fewer side effects.

Combination of mesenchymal stem cell injection with icariin for the treatment of diabetes-associated erectile dysfunction

The present study was aimed to examine whether icariin, a traditional Chinese medicine, could improve therapeutic effects of adipose derived mesenchymal stem cells (ADSCs) for diabetes-associated erectile dysfunction (DMED). DMED were induced in rats by intraperitoneal injection of streptozotocin and confirmed by erectile function measurement. Then, rats of diabetic ED were randomly divided to receive the treatment of saline, ADSCs, icariin or ADSCs combined with icariin respectively. Compared with the treatment by ADSCs or icariin alone, intracavernosum injection of ADSCs combined with the following daily gastric gavage of icariin significantly augmented the value of ICP and ICP/MAP (p<0.01). Meanwhile, the survival of transplanted ADSCs was much improved due to the application of icariin. Similarly, immunofluorescent staining analysis demonstrated that the improved erectile tissue structure by combination of ADSCs and icariin was significantly associated with the increased expression of endothelial markers (vWF) (p<0.01) and smooth muscle markers (α-SMA) (p<0.01). Furthermore, the structure changes in corpus cavernosum were further confirmed by the Masson’s trichrome staining. To explore the possible mechanism underlying icariin-enhanced therapeutic efficacy of MSCs, we employed an in vitro testing system by introducing H₂O₂ to imitate oxidative stress condition considering the oxidative environment faced by engrafted ADSCs and anti-oxidative capacity of icariin_.In vitro, we found that the addition of icariin considerably reduced the apoptosis of ADSCs, and attenuated the intracellular reactive oxygen species (ROS), the superoxidase dismutase (SOD) activity and the lactate dehydrogenase (LDH). Subsequently, we examined the expression of apoptosis-related proteins and explored the potential signaling pathway through which icariin promoted the survival of ADSCs against oxidative stress. It was demonstrated that icariin significantly inhibited the upregulation of apoptosis-related proteins under oxidative condition, including Bax and cleaved caspase-3, while promoted the expression of anti-apoptotic factor BCL2. These effects were accompanied with the activation of signal molecules, PI3K/Akt and STAT3. The further signal protein inhibition assays exhibited that the suppression of STAT3 abrogated the icariin-mediated anti-apoptotic effects observed above, while did not influence the expression of PI3K/Akt. However, PI3K inhibition could abrogate icariin–mediated STAT3 activation and achieved a similar effect as STAT3 inhibition. Our results suggested that icariin was an effective adjuvant for enhancing ADSC-based therapy of DMEM, which may be ascribed to their protection of ADSCs against oxidative stress via the regulation of PI3K/Akt-STAT3 signal pathway.

Psychosexual disorders and dermatologists

Sexual problems that are psychological in origin, rather than physiological, are called psychosexual disorders. Multiple factors, such as general health of the patient, chronic illnesses, psychiatric/psychological disorders, and socio-cultural factors, alone or in combination can be attributed to the development of psychosexual dysfunctions. The symptoms of these disorders vary for each individual and differ with gender. These disorders may be categorized as sexual dysfunction, paraphilias, and gender identity disorders. Dermatologists are sometimes consulted for sexual dysfunctions in their routine practice by the patients visiting sexually transmitted infections (STI) clinics because a majority of the patients believe that these problems are caused by dysfunctions in the sex organs, and because people are hesitant to go to sexuality clinics and psychiatrists for such problems. Sometimes these patients are referred from other specialties such as urology or gynecology; most often, we attempt to search for STIs or other dermatoses on the genitalia and refer them back. We often underestimate the prevalence of sexual concerns of the patients or feel uncomfortable discussing matters of sexuality with them. Dermatologists should understand basic sexual medicine and ask patients for sexual problems. They should be trained to manage such patients accordingly. In this review, we will be focusing on sexual dysfunctions, their etiopathogenesis, and management from a dermatologist's perspective.

Pharmacogenetics of erectile dysfunction: navigating into uncharted waters

Sildenafil and other PDE-5 inhibitors have revolutionized erectile dysfunction (ED) treatment. However, a significant number of patients do not respond or present adverse reactions to these drugs. While genetic polymorphisms may underlie this phenomenon, very little research has been undertaken in this research field. Most of the current knowledge is based on sildenafil, thus almost completely ignoring other important pharmacological therapies. Currently, the most promising genes with pharmacogenetic implications in ED are related to the nitric oxide and cGMP pathway, although other genes are likely to affect the responsiveness to treatment of ED. Nevertheless, the small number of studies available opens the possibility of further exploring other genes and phenotypes related to ED. This article provides a comprehensive overview of the genes being tested for their pharmacogenetic relevance in the therapy of ED.

Hypoxia precondition promotes adipose-derived mesenchymal stem cells based repair of diabetic erectile dysfunction via augmenting angiogenesis and neuroprotection

The aim of the present study was to examine whether hypoxia preconditioning could improve therapeutic effects of adipose derived mesenchymal stem cells (AMSCs) for diabetes induced erectile dysfunction (DED). AMSCs were pretreated with normoxia (20% O₂, N-AMSCs) or sub-lethal hypoxia (1% O₂, H-AMSCs). The hypoxia exposure up-regulated the expression of several angiogenesis and neuroprotection related cytokines in AMSCs, including vascular endothelial growth factor (VEGF) and its receptor FIK-1, angiotensin (Ang-1), basic fibroblast growth factor (bFGF), brain-derived neurotrophic factor (BDNF), glial cell-derived neurotrophic factor (GDNF), stromal derived factor-1 (SDF-1) and its CXC chemokine receptor 4 (CXCR4). DED rats were induced via intraperitoneal injection of streptozotocin (60 mg/kg) and were randomly divided into three groups—Saline group: intracavernous injection with phosphate buffer saline; N-AMSCs group: N-AMSCs injection; H-AMSCs group: H-AMSCs injection. Ten rats without any treatment were used as normal control. Four weeks after injection, the mean arterial pressure (MAP) and intracavernosal pressure (ICP) were measured. The contents of endothelial, smooth muscle, dorsal nerve in cavernoursal tissue were assessed. Compared with N-AMSCs and saline, intracavernosum injection of H-AMSCs significantly raised ICP and ICP/MAP (p<0.05). Immunofluorescent staining analysis demonstrated that improved erectile function by MSCs was significantly associated with increased expression of endothelial markers (CD31 and vWF) (p<0.01) and smooth muscle markers (α-SMA) (p<0.01). Meanwhile, the expression of nNOS was also significantly higher in rats receiving H-AMSCs injection than those receiving N-AMSCs or saline injection. The results suggested that hypoxic preconditioning of MSCs was an effective approach to enhance their therapeutic effect for DED, which may be due to their augmented angiogenesis and neuroprotection.

Clinical Efficacy and Safety of Vitaros©/Virirec© (Alprostadil Cream) for the Treatment of Erectile Dysfunction

Erectile dysfunction (ED) is a very common disorder with a deep impact on patients and their partners. Several options are now available for treating ED; oral pharmacotherapy with phosphodiesterase-5 (PDE5) inhibitors currently represents the first-line option for many ED patients. Vitaros©/Virirec© is new topical, non-invasive treatment for ED that offers the combination of an active drug (alprostadil, a synthetic PGE1) with a skin enhancer that improves its local absorption directly at the site of action. Vitaros©/Virirec© has a favorable pharmacodynamic profile and is poorly absorbed in systemic circulation. This makes it suitable in any circumstances and results in a reduced risk of adverse events (AEs), being systemic AEs reported in only 3% of the treated population. Its clinical efficacy has been demonstrated in both phase II and III trials, showing a global efficacy up to 83% with the 300 μg dose in patients with severe ED significantly better than placebo. Its fast onset of action together with its favorable toxicity profile and lack of interactions with other drugs makes Vitaros©/Virirec© a first-line therapeutic option for patients with ED, particularly for individuals who are reluctant to take systemic treatments or with AEs. It may also have an important role in patients not responding to PDE5 inhibitors, particularly those with ED after radical prostatectomy.

Efficacy and safety of long-term tadalafil 5 mg once daily combined with sildenafil 50 mg as needed at the early stage of treatment for patients with erectile dysfunction

This study aimed to evaluate the efficacy and safety of long-term and low-dose tadalafil combined with sildenafil as needed at the early stage of treatment for erectile dysfunction (ED). We enrolled 180 patients with ED 1 : 1 to tadalafil 5 mg once daily or once-a-day tadalafil 5 mg combined with sildenafil 50 mg as needed. The efficacy measures included the 5-item version of the International Index of Erectile Function (IIEF-5) and the Sexual Encounter Profile (SEP). The safety was assessed by observing drug tolerability and adverse events. Total IIEF-5 scores of patients with severe ED in combined medication group were significantly higher than in tadalafil alone group. Question 2 scores of IIEF-5 of patients with moderate and severe ED in combined medication group were significantly higher than in tadalafil alone group. The significant improvement in question 3 scores of IIEF-5 existed only in patients with severe ED receiving combined medication. The percentage of 'yes' responses to SEP4, SEP5 and partner's SEP3 were improved significantly in combined medication group. There was no difference between two groups in the incidence of adverse events. Our results suggest that combined medication can better improve erectile function, especially for patients with severe ED.

Diabetes and sexual dysfunction: current perspectives

Diabetes mellitus is one of the most common chronic diseases in nearly all countries. It has been associated with sexual dysfunction, both in males and in females. Diabetes is an established risk factor for sexual dysfunction in men, as a threefold increased risk of erectile dysfunction was documented in diabetic men, as compared with nondiabetic men. Among women, evidence regarding the association between diabetes and sexual dysfunction are less conclusive, although most studies have reported a higher prevalence of female sexual dysfunction in diabetic women as compared with nondiabetic women. Female sexual function appears to be more related to social and psychological components than to the physiological consequence of diabetes. Hyperglycemia, which is a main determinant of vascular and microvascular diabetic complications, may participate in the pathogenetic mechanisms of sexual dysfunction in diabetes. Moreover, diabetic people may present several clinical conditions, including hypertension, overweight and obesity, metabolic syndrome, cigarette smoking, and atherogenic dyslipidemia, which are themselves risk factors for sexual dysfunction, both in men and in women. The adoption of healthy lifestyles may reduce insulin resistance, endothelial dysfunction, and oxidative stress - all of which are desirable achievements in diabetic patients. Improved well-being may further contribute to reduce and prevent sexual dysfunction in both sexes.

A Quality Analysis of Randomized Controlled Trials about Erectile Dysfunction

Purpose

A low quality clinical trial could produce errors, and these errors could, in turn, distort the results of the clinical trial. To avoid applying distorted results of trials clinically, a quality analysis of clinical trials is needed.

Materials and Methods

We selected randomized controlled trials (RCTs) about erectile dysfunction (ED) conducted in Korea using Medline and KoreaMed. Quality assessment of selected RCTs was performed using three assessment tools (Jadad scales, van Tulder scale, Cochrane Collaboration Risk of Bias Tool [CCRBT]).

Results

The first RCT about ED conducted in Korea was published in 2002. Since 2002, a total of 20 RCTs have been published in medical journals. Among the 20 articles, only 1 article was found to have a low risk of bias according to the CCRBT. On the Jadad scale, there were 17 high quality articles, while 19 articles were assessed as high quality by the VTS. Only 2 RCTs described the randomization method adequately. Only 1 RCT presented allocation concealment.

Conclusions

A low quality clinical trial could produce errors, and these errors could, in turn, distort the results of the clinical trial. To avoid applying distorted results of trials clinically, a quality analysis of clinical trials is needed. The quality of RCTs was found to be high because almost all of the selected RCTs were double blinded studies. However, the quality of RCTs was inadequate with regard to the lack of randomization and absence of allocation concealment. Therefore, performing adequate randomization and adding a description of the appropriate concealment of allocation may improve the quality of RCTs.

Erectile dysfunction

Erectile dysfunction is a common clinical entity that affects mainly men older than 40 years. In addition to the classical causes of erectile dysfunction, such as diabetes mellitus and hypertension, several common lifestyle factors, such as obesity, limited or an absence of physical exercise, and lower urinary tract symptoms, have been linked to the development of erectile dysfunction. Substantial steps have been taken in the study of the association between erectile dysfunction and cardiovascular disease. Erectile dysfunction is a strong predictor for coronary artery disease, and cardiovascular assessment of a non-cardiac patient presenting with erectile dysfunction is now recommended. Substantial advances have occurred in the understanding of the pathophysiology of erectile dysfunction that ultimately led to the development of successful oral therapies, namely the phosphodiesterase type 5 inhibitors. However, oral phosphodiesterase type 5 inhibitors have limitations, and present research is thus investigating cutting-edge therapeutic strategies including gene and cell-based technologies with the aim of discovering a cure for erectile dysfunction.

Diabetes-induced erectile dysfunction: epidemiology, pathophysiology and management

Erectile dysfunction (ED) is defined as the inability of the male to attain and maintain erection of penis sufficient to permit satisfactory sexual intercourse. Prevalence of impotence in diabetic men is ≥50%. The pathophysiology of diabetes-induced erectile dysfunction (DIED) is multifactorial and no single etiology is at the forefront. The proposed mechanisms of erectile dysfunction in diabetic patients includes elevated advanced glycation end-products, increased levels of oxygen free radicals, impaired nitric oxide synthesis, increased endothelin B receptor binding sites and up-regulated RhoA/Rho-kinase pathway, neuropathic damage and impaired cyclic guanosine monophosphate (cGMP)-dependent protein kinase-1. The treatment of DIED is multimodal. Treatment of the underlying hyperglycemia and comorbidities is of utmost importance to prevent or halt the progression of disease. Oral medications are considered as the first line therapy for management of DIED. If oral agents cannot be used or have insufficient efficacy despite appropriate dosing and education, second-line treatments should be addressed. When there is lack of efficacy or when there is dissatisfaction with other modalities, penile prostheses are often the best alternative for ED and are considered as the third line therapy for DIED. Future strategies in the evolution of the treatment of DIED are aimed at correcting or treating the underlying mechanisms of DIED.

In vitro and in vivo studies on the importance of the soluble guanylyl cyclase α1 subunit in penile erection

PURPOSE

Soluble guanylyl cyclase (sGC), which plays a pivotal role in penile erection, is a heterodimer build up by an α and a β subunit. For both subunits two isoforms have been characterized, but only the sGCα(1)β(1) and sGCα(2)β(1) isoforms seem to be functionally active. To elucidate the functional role of the sGCα(1)β(1) heterodimer in the mechanism of erection, experiments were performed in vivo and on isolated corpora cavernosa (CC) using sGCα(1)(-/-) mice.

MATERIALS AND METHODS

For the in vivo study sGC-dependent and -independent vasorelaxing agents were injected intracavernosally in sGCα(1)(-/-) and sGCα(1)(+/+) mice and the rise in intracavernosal pressure was recorded. For the in vitro study, isolated CC tissues from sGCα(1)(-/-) and sGCα(1)(+/+) mice were mounted in organ baths for isometric tension recording and concentration-dependent curves were obtained for sGC-dependent and -independent vasorelaxing agents. These experiments were performed on 2 different mice strains (129SvEvS7 and C57BL6/J) to determine potential strain differences.

RESULTS

The responses in sGCα(1)(-/-) after administration of the NO-donors, sodium nitroprusside (SNP) and spermine-NO, and to electrical stimulation are significantly reduced although not completely abolished. Responses to sGC-independent vasorelaxing agents are similar in sGCα(1)(-/-) and sGCα(1)(+/+) mice from both strains suggesting that the decreased potential of smooth muscle relaxation is not related to structural changes or changes in the pathway downstream sGC.

CONCLUSION

This study illustrates the strain-independent importance of the sGCα(1)β(1) heterodimer, although remaining vasorelaxing responses in the sGCα(1)(-/-) mice suggest a complementary role for the sGCα(2)β(1) isoform or (an) sGC-independent mechanism(s).

Chuanxiongzine relaxes isolated corpus cavernosum strips and raises intracavernous pressure in rabbits

It has been shown that there are many Chinese traditional herbals that can enhance sexual activity. Chuanxiongzine is a vasoactive ingredient that has been isolated and purified from Ligusticum chuanxiong Hort. In previous studies, it has been found that chuanxiongzine was effective in relaxing rabbit corpus cavernosum smooth muscle. We determined the effects of chuanxiongzine on relaxation of isolated corpus cavernosum strips in vitro and on increase of intracavernous pressure (ICP) in vivo in rabbits. Chuanxiongzine caused a concentration-dependent relaxation of phenylephrine precontracted isolated corpus cavernosum strips (EC₅₀ 1.58 × 10⁻⁴ mol l⁻¹), which were endothelium independent and NO independent. However, the guanylyl cyclase inhibitor 1-H-[1,2,4] oxadiazolo [4,3-a] quinoxalin-1-one significantly shifted the chuanxiongzine concentration–response relationship to the right. Although there was no significant difference in the level of cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP) in isolated corpus cavernosum strips treated with chuanxiongzine or vehicle, chuanxiongzine caused a significant rise in the level of cGMP and cAMP in isolated corpus cavernosum strips pretreated with the activator of adenylyl cyclase forskolin and the source of NO sodium nitroprusside. In an in vivo study, chuanxiongzine dose-dependently raised ICP after the intracavernous injection of its cumulative doses (0.5, 1, 2 and 5 mg kg⁻¹). The ICP increased from baseline to 19.1±3.7, 24.8±2.1, 30.2±4.8 and 39.7±6.1 mm Hg, respectively, and the duration of tumescence ranged from 8.5±2.8 to 22.9±7.3 min. Our results show that chuanxiongzine can relax isolated corpus cavernosum strips of rabbits in vitro and increase ICP of rabbits in vivo, which is neither endothelium dependent nor NO dependent, but may be partly mediated by the inhibition of cAMP phosphodiesterase or cGMP phosphodiesterase.

Sexual dysfunction in multiple sclerosis

Multiple sclerosis is a chronic disease that commonly affects young adults who may be sexually active. Sexual dysfunction is a significant, but often underestimated, symptom of multiple sclerosis, affecting 50-90% of men and 40-80% of women. The types of sexual dysfunction can be categorized in terms of the normal sexual response cycle: sexual interest/desire dysfunction (reduced libido), sexual arousal dysfunction (including erectile dysfunction) and ejaculatory and orgasmic dysfunction. Sexual dysfunction may not only be due to lesions affecting the neural pathways involved in physiological function (primary dysfunction), but also result from general physical disabilities (secondary dysfunction) or psychological and emotional issues (tertiary dysfunction). Comprehensive management should address all these possible contributing problems. Specific pharmacotherapy is only currently available for erectile dysfunction. This review summarizes the available information about sexual dysfunction in men and women with multiple sclerosis.