ORAL PHENTOLAMINE AS TREATMENT FOR ERECTILE DYSFUNCTION

Effect of alpha-adrenoceptor antagonists on sexual function. A systematic review and meta-analysis

BACKGROUND

Alpha-adrenoreceptor antagonists or alpha-blockers are used in the treatment of hypertension, in the therapy of benign prostatic hyperplasia and in medical expulsive treatment of ureteral stones. These agents may affect the sexual function, with differences between drugs within the same class, depending on their selectivity for receptor subtypes. The aim of this review was to analyze the effects of alpha-blockers on sexual function.

MATERIALS AND METHODS

We conducted a systematic review and meta-analysis by searching PubMed, EMBASE and other databases for randomized controlled trials (RCTs) reporting sexual adverse effects in patients treated with alpha-blockers. Odds ratios for sexual dysfunction were calculated using random effects Mantel-Haenszel statistics.

RESULTS

Out of 608 records retrieved, 75 eligible RCTs were included in the meta-analysis. Compared with placebo, alphablockers were associated with increased odds of ejaculatory disorders both in patients with lower urinary tract symptoms (LUTS) associated to benign prostatic hyperplasia (BPH) (OR: 7.53, 95% CI: 3.77-15.02, Z = 5.73, p < 0.00001, I2 = 55%) and in patients with ureteral stones (OR: 2.88, 95% CI: 1.50-5.44, Z = 3.19, p < 0.001, I2 = 31%). Uroselective alpha-blockers showed higher odds of ejaculatory disorders. Conversely, nonselective alpha-blockers were not associated with higher odds of ejaculatory dysfunction. Silodosin was associated with increased odds of ejaculatory dysfunction compared with tamsulosin (OR: 3.52, 95% CI: 2.18-5.68, 15 series, 1512 participants, Z = 5.15, p < 0.00001, I2 = 0%). Naftopidil and alfuzosin showed lower odds of ejaculatory dysfunction compared to uroselective alpha-blockers.No statistically significant differences in the odds of erectile dysfunction were observed when alpha-blockers were compared to placebo.

Efficacy of Long-Term Daily Dosage of Alfuzosin 10 mg upon Sexual Function of Benign Prostatic Hypertrophy Patients: Two-Year Prospective Observational Study

Purpose

To identify sexual function improvement associated with alfuzosin (10 mg daily for 2 years).

Materials and Methods

We enrolled 30 men with lower urinary tract symptom (LUTS) who visited Gyeongsang National University Hospital between 2010 and 2012. At first visit, urinalysis, prostate specific antigen, transrectal ultrasound, and uroflowmetry were performed. The nternational Prostate Symptom Score (IPSS), quality of life (QoL), International Index of Erectile Function (IIEF), and Male Sexual Health Questionnaire Ejaculation Function Domain (MSHQ-EjFD) questionnaires were administered, and the subjects answered the same questionnaires at 1 month, 6 months, 1 year, and 2 years of follow-up.

Results

Twelve men completed of the entire study. After administration of alfuzosin, the median IPSS at first visit, 1 month, 6 months, 1 year, and 2 years was 18.00 (interquatile range [IQR]: 14.00~29.75), 20.00 (IQR: 11.50~30.00), 15.50 (IQR: 8.50~25.25), 14.50 (IQR: 9.25~19.50), and 11.50 (IQR: 5.00~17.75), respectively, which showed an improvement. The median QoL at the same times was 4.50 (IQR: 4.00~5.00), 4.50 (IQR: 4.00~5.00), 3.00 (IQR: 2.00~4.00), 3.50 (IQR: 2.25~4.00), and 3.00 (IQR: 1.00~3.00), respectively, and also showed improvement. Likewise, the median IIEF was 36.50 (IQR: 24.50~46.75), 37.50 (IQR: 26.75~47.25), 45.50 (IQR: 35.00~59.75), 48.50 (IQR: 34.75~62.75), and 47.50 (IQR: 43.25~61.00), while the median MSHQ-EjFD was 19.00 (IQR: 12.0~24.75), 19.50 (IQR: 13.50~27.75), 23.00 (IQR: 19.25~32.25), 26.50 (IQR: 18.25~34.50), 27.00 (IQR: 21.50~32.50), respectively, with both showing improvement.

Conclusions

After administration of alfuzosin (10 mg daily for 2 years), the IPSS, QoL, IIEF, and MSHQ-EjFD all improved significantly. This means long-term administration of 10 mg of alfuzosin daily would be effective not only for LUTS but also erectile function and ejaculation.

Mechanisms of penile erection and basis for pharmacological treatment of erectile dysfunction

Erection is basically a spinal reflex that can be initiated by recruitment of penile afferents, both autonomic and somatic, and supraspinal influences from visual, olfactory, and imaginary stimuli. Several central transmitters are involved in the erectile control. Dopamine, acetylcholine, nitric oxide (NO), and peptides, such as oxytocin and adrenocorticotropin/α-melanocyte-stimulating hormone, have a facilitatory role, whereas serotonin may be either facilitatory or inhibitory, and enkephalins are inhibitory. The balance between contractant and relaxant factors controls the degree of contraction of the smooth muscle of the corpora cavernosa (CC) and determines the functional state of the penis. Noradrenaline contracts both CC and penile vessels via stimulation of α₁-adrenoceptors. Neurogenic NO is considered the most important factor for relaxation of penile vessels and CC. The role of other mediators, released from nerves or endothelium, has not been definitely established. Erectile dysfunction (ED), defined as the "inability to achieve or maintain an erection adequate for sexual satisfaction," may have multiple causes and can be classified as psychogenic, vasculogenic or organic, neurologic, and endocrinologic. Many patients with ED respond well to the pharmacological treatments that are currently available, but there are still groups of patients in whom the response is unsatisfactory. The drugs used are able to substitute, partially or completely, the malfunctioning endogenous mechanisms that control penile erection. Most drugs have a direct action on penile tissue facilitating penile smooth muscle relaxation, including oral phosphodiesterase inhibitors and intracavernosal injections of prostaglandin E₁. Irrespective of the underlying cause, these drugs are effective in the majority of cases. Drugs with a central site of action have so far not been very successful. There is a need for therapeutic alternatives. This requires identification of new therapeutic targets and design of new approaches. Research in the field is expanding, and several promising new targets for future drugs have been identified.

[From lab to clinical activity: adrenergic receptors and human uro-genital tissues]

BACKGROUND

Nowadays translational medicine is acquiring a more and more important role in connecting laboratory experimental results on human tissues to clinical findings and drug employment. We want to underline the importance of in vitro studies, which have been extensively performed on animal organs, but few studies have been performed on human tissues. Nevertheless, a more accurate result when compared to the in vivo use of drugs can be given only by testing the very same human tissues in a lab. We related clinical treatments of different pathologies with the results obtained in laboratory studying in vitro fragments of human organs extracted during surgery exposed to different mediators and drugs.

METHODS

Fragments of urethers, bladder (detrusorial muscle and bladder neck muscle fibers), corpora cavernosa, and vas deferens were extracted during demolitive surgery trying not to traumatize the tissue, in order to keep it alive and not to ruin its contractile fibers. The fragments were then put into polisaline solution and, once in the laboratory, fixed on suitable isolated organ support, fixed at one side of the thermostatic pool and on the other side connected to a digital monitoring system. The contractility was then studied after adding different mediators.

RESULTS

The urethers have shown a stronger response to NE and PGF2a, with a different contractility in their distal part due to a major concentration of alpha-receptors; the bladder neck has also shown a strong contractile response to NE and PGF2a, and is inhibited by alpha-blockers; the bladder detrusor, instead, responds to ACH (acetylcholine) and PGF2a; the vas deferens shows a different type of contractility in the prostatic part compared to the epididimary part when stimulated with noradrenaline and PGF2a; the corpora cavernosa respond to NE and PGF2a.

CONCLUSIONS

The results obtained after stimulating the fragments can explain and prove the receptorial activity of inner mediators and of commonly used drugs which have, for years, been used empirically; the simplicity and repetitivity of the method can be considered and used not only to research the physiological functioning of different organs, but also the functioning of new drugs before testing them on patients, being more reliable and accurate than tests on animal tissues. This experimental work has shown that using human tissues in testing specific mediators is the most reliable laboratory method.

Outcomes and quality of life issues in the pharmacological management of benign prostatic hyperplasia (BPH)

BACKGROUND

Benign prostatic hyperplasia (BPH) is a common disease of the aging male population. BPH treatment includes a variety of pharmacological and surgical interventions. The goal of this paper is to review the natural history of BPH, outcomes of pharmacological management, effects on quality of life (QoL), future pharmacotherapies, and associated patient-focused perspectives.

MATERIALS AND METHODS

Medline searches for the keywords benign prostatic hyperplasia, BPH, alpha blockers, 5 alpha-reductase, and quality of life were performed. Relevant literature was reviewed and analyzed.

RESULTS

Alpha blockers, 5 alpha-reductase inhibitors, and phytotherapy are the three categories of pharmaceutical interventions currently available for BPH. Various clinical trials have shown that alpha blockers and 5 alpha-reductase inhibitors are safe, efficacious, and improve QoL in patients with BPH. The evidence for phytotherapeutics is not as convincing. The current armamentarium of pharmaceutical interventions are encompassed in these three classes of medications. New pharmacotherapies based on novel mechanisms are on the horizon.

CONCLUSION

There are a variety of safe and efficacious medical therapies available for the management of BPH and it is important for the practicing physician to have an understanding of these pharmacotherapies and their potential impact on the patient. There is not enough evidence to make a recommendation regarding phytotherapy use. New classes of drugs for BPH will likely find their way into routine use.

The cardiovascular response to sexual activity: do we know enough?

Interest in comprehensive cardiac rehabilitation over the past 25 years spawned a series of small investigations concerning the heart rate, blood pressure, and ischemic response to sexual intercourse. This information was adequate for advising patients about return to sexual activity after a myocardial infarction or cardiac surgery. However, the introduction of medications for erectile dysfunction enabled impotent cardiac patients to engage in sexual activity and has highlighted the need for more detailed information concerning cardiovascular physiology during coitus. Review of the medical literature indicates a remarkable paucity of such data despite dramatic advances in most other aspects of cardiovascular physiology and pathophysiology. This brief paper gives an overview of the current knowledge of the cardiovascular response to sexual activity and, within the framework of advances in cardiology, highlights areas where it appears important to fill in the knowledge gap.

Combination of alfuzosin and tadalafil exerts in vitro an additive relaxant effect on human corpus cavernosum

INTRODUCTION

Phosphodiesterase type 5 (PDE5) inhibitors, such as tadalafil, are a first-line treatment for erectile dysfunction (ED). Nevertheless, some patients do not respond to this treatment. Clinical data suggest that the addition of alpha1-adrenoceptor blocker, such as alfuzosin, commonly prescribed for lower urinary tract symptoms suggestive of benign prostatic hyperplasia, may be of benefit. Aim. Evaluation of the effect of alfuzosin, tadalafil or the combination of both on human corpus cavernosum.

METHODS

Human cavernosal tissues were obtained from 10 patients undergoing penile surgery. Strips contractility was studied in organ baths. Concentration-response curves to tadalafil were generated on norepinephrine (NE, 1-10 microM)-precontracted strips in the presence of alfuzosin or vehicle. Frequency-response curves (FRC) to electrical field stimulation (EFS, 0-64 Hz, 3 ms, 10 seconds, 300 mA) were generated in the presence of vehicle, alfuzosin, tadalafil, or both drugs combined. EFS (20 Hz, 1 ms, 10 seconds, 300 mM)-induced nitrergic relaxation on NE-precontracted strips was studied in the presence of vehicle, alfuzosin, tadalafil, or both drugs combined.

MAIN OUTCOME MEASURES

Functional measurement of cavernosal smooth muscle relaxation in the presence of tadalafil and alfuzosin.

RESULTS

The relaxation induced by tadalafil (10(-10) to 10(-5) M) on precontracted strips was enhanced by alfuzosin at both 10(-8) and 10(-7) M. The combination of alfuzosin (3.10(-8) M) and tadalafil (10(-7) M) was more efficient to inhibit FRC-induced contractions than each compound alone. The combination of tadalafil (10(-6) M) and alfuzosin (10(-8) M) increased the relaxation induced by EFS and its effect was greater than tadalafil alone. In addition, the combination of tadalafil (10(-6) M) and alfuzosin (10(-7) M) prolonged EFS-induced relaxation to a greater extent than each compound alone.

CONCLUSIONS

In vitro, the combination of alfuzosin and tadalafil is more efficient than each compound alone to relax adrenergic tone or to enhance nitrergic relaxation of the human corpus cavernosum. Such a combination deserves further investigation in placebo-controlled studies to evaluate its benefit in ED patients who are not sufficiently improved by PDE5 inhibitors.

The future of the oral pharmacotherapy of male erectile dysfunction: things to come

The convincing clinical data on the use of the orally active phosphodiesterase inhibitors sildenafil, vardenafil and tadalafil for the treatment of male erectile dysfunction have boosted research activities on the physiology of the male erectile mechanism. This included both peripheral intracellular signal transduction in the corpus cavernosum as well as central brain and spinal cord pathways controlling penile erection. This work provided the basis for the development and introduction of several new therapeutic modalities into the management of erectile dysfunction, some of which are already offered to the patients. As the concept of 'taking a pill' as a cure for an illness or the relief of symptoms of a disease has become widely accepted by the consumers, the pharmacologic treatment of erectile dysfunction has primarily focussed on selective, orally available drugs acting by influencing intracellular or central regulatory mechanisms, combining a high response rate and the advantage of an on-demand intake. These agents are regarded as more efficacious, and have a faster onset of drug action in the target tissue and an improved effect to side-effect ratio. The purpose of this review is to describe the major novel and evolving pharmacologic advances in the field of oral pharmacotherapy for the treatment of male erectile dysfunction.

Pharmacology of α1-adrenoceptor antagonists in the lower urinary tract and central nervous system

The main use of alpha(1)-adrenoceptor (AR) antagonists in urology has been to treat lower urinary tract symptoms (LUTS) in men with benign prostatic obstruction (BPO). The beneficial effects of these agents are primarily assumed to be because of relaxation of prostatic and urethral smooth muscle. The weak correlation between LUTS and prostatic enlargement, outflow obstruction, or both, however, has refocused interest on the role of extraprostatic alpha-ARs in the pathogenesis of LUTS and their treatment. The alpha(1)-ARs present in the bladder, urethra, vas deferens, peripheral ganglia, nerve terminals, and in the central nervous system could all potentially influence LUTS and, when the receptors are blocked, contribute to both the therapeutic and adverse effects of alpha(1)-AR antagonists. The relevance of alpha(1)-AR-subtype selectivity on the clinical usefulness of existing drug therapies has not been firmly established but it seems that blockade of both alpha(1A/L)- and alpha(1D)-ARs is necessary for the optimum balance between clinical efficacy and adverse effects.

Effects of ??1-Adrenoceptor Antagonists on Male Sexual Function

alpha(1)-Adrenoceptor antagonists such as alfuzosin, doxazosin, tamsulosin and terazosin are first-line agents for the treatment of lower urinary tract symptoms suggestive of benign prostatic hyperplasia (BPH), but are only second-line agents (doxazosin and terazosin only) for the treatment of arterial hypertension. Sexual function is complex and includes multiple domains such as sexual desire (libido), erectile function and ejaculatory function. Erectile and ejaculatory functions are frequently reduced in patients with BPH and can impact on their quality of life. Therefore, the treatment of BPH should aim to maintain or even restore sexual function.alpha(1)-Adrenoceptor antagonists lack major effects on sexual desire in placebo-controlled studies. Reports on erectile function are inconsistent, with both beneficial and adverse effects being reported, but impotence can occur in some patients without clear differences between drugs. Ejaculatory dysfunction during treatment may represent (relative) an ejaculation. It occurs more frequently with tamsulosin than with other drugs of this class, but the differences are not big enough to be consistently detectable in directly comparative studies. We propose that such differences between drugs should be weighed against differences in cardiovascular tolerability when choosing the optimal treatment for each patient.

Flow-injection chemiluminescence determination of phentolamine based on its enhancing effect on the luminol–potassium ferricyanide system

It was found that the light emission produced by the oxidation of luminol by potassium ferricyanide in the basic medium was enhanced by phentolamine, a drug recently used to treatment of male and female sexual dysfunction. The optimum conditions for this chemiluminescent reaction were studied in detail by a flow-injection system. A new, simple and rapid method has been developed under the optimum conditions for determination of phentolamine. This method has the advantages of high sensitivity, good reproducibility and low detection limit. On the basis of investigation of chemiluminescent, fluorescent and UV spectra of phentolamine in basic solution containing potassium ferricyanide and luminol, a possible mechanism of this reaction was proposed. In the optimum conditions, CL intensities are proportional to concentrations of the phentolamine in the 0.01-1 microg/mL range. The limit of detection is 3.0 ng/mL for phentolamine. The method has been applied to the determination of phentolamine in the commercial preparations, synthetic samples and biological fluids with satisfactory results.

Enlarging the scope of managing benign prostatic hyperplasia: addressing sexual function and quality of life

Benign prostatic hyperplasia is a common genitourinary disorder that increases in incidence with age. Symptoms of this condition include a weak urinary stream, hesitancy, intermittency and sensations of incomplete emptying, as well as frequency, urgency, urge incontinence and nocturia. These symptoms can be ameliorated successfully by a variety of medical treatments - such as alpha(1)-adrenergic blockade and 5-alpha-reductase inhibition - and surgical therapies - including transurethral resection of the prostate and less-invasive procedures. However, many of the treatments are known to result in sexual dysfunction, which can have a negative impact on the patient's quality of life. This must be considered when the physician seeks to determine the appropriate treatment for an individual patient. Current reports suggest that alpha(1)-adrenergic blockade is most likely to improve lower urinary tract symptoms while resulting in the fewest sexual side-effects; 5-alpha-reductase inhibitors appear to be particularly appropriate in men with large prostates. Among surgical therapies, transurethral resection of the prostate remains the gold standard, but is associated with a high incidence of sexual side-effects, especially retrograde ejaculation. Transurethral incision of the prostate, which is an endoscopic procedure, may be as effective as transurethral resection, but results in fewer side-effects. Minimally invasive procedures, including laser ablation or resection of the prostate, transurethral microwave thermotherapy and transurethral needle ablation, are rapidly evolving technologies that have demonstrated promising results, at least in the short term.

4-Aryl-3-(mercapto)quinolin-2-ones: novel maxi-K channel opening relaxants of corporal smooth muscle

A novel series of 4-aryl-3-(mercapto)quinolin-2-one derivatives was prepared and evaluated as openers of the cloned maxi-K channel hSlo expressed in Xenopus laevis oocytes by utilizing electrophysiological methods. The effect of these maxi-K openers on corporal smooth muscle was studied in vitro using isolated rabbit corpus cavernosum. In vivo efficacy has been demonstrated with a selective maxi-K opening relaxant in a rat model of erectile function.

Advances in the Treatment of Erectile Dysfunction: A Focus on Tadalafil

Erectile dysfunction (ED) affects more than 150 million men and their partners throughout the world. Sildenafil, the first oral phosphodiesterase-type 5 (PDE-5) inhibitor approved for the treatment of ED, has led to the discovery of 2 more products in this class, with tadalafil being the latest. Tadalafil has proven to be well tolerated in various clinical studies and has demonstrated effectiveness in men with mild to severe ED, regardless of severity, etiology, or age. One major characteristic that may distinguish tadalafil from other oral PDE-5 inhibitors is its extensive duration of effect. Tadalafil has a therapeutic duration of up to 36 hours that may allow patients to engage in sexual activity at their own convenience rather than in a limited time period. This, along with other clinical and practical advantages, should make tadalafil an attractive alternative to currently available treatments options. This article summarizes the pharmacology, pharmacokinetics, adverse effects, and clinical efficacy of tadalafil.

Update on oral treatments for male erectile dysfunction

Impairment of erectile function compromises quality of life in millions of men and their partners, many of whom prefer to suffer in silence. It is important to maintain an elevated index of clinical suspicion in patients with erectile dysfunction (ED) risk factors (e.g. hypertension, diabetes, coronary heart disease). There remains a high rate of voluntary discontinuation of therapy associated with most treatment modalities. Since the introduction of sildenafil, a greater awareness and openness regarding the epidemiology and treatment of male erectile dysfunction has emerged. The development of newer and potentially more efficacious phosphodiesterase type 5 (PDE5) inhibitors will serve to treat an even greater number of patients, allowing once daily and more convenient dosing. An increased understanding of the physiological principles of penile erection has allowed the development of novel oral pharmacological therapies. The new agents offer a potential benefit in a broader range of patients and clinical situations. They may provide a more acceptable alternative than other more invasive options (intracavernosal/urethral injection, implant surgery). The dopamine agonist apomorphine acts on the central control of penile erection to allow a sublingual preparation to produce a prompt response. It is not contraindicated in patients on nitrate medication for coronary artery disease, or in patients with depression or on antidepressants. As with any other treatment, the clinician's responsibility in the care of ED patients does not end with the writing of a prescription. Adequate education and follow-up are needed to optimize the efficacy and safety of oral ED therapy. Furthermore, patients and their partners need to be advised that the agents are not effective in the absence of sexual stimulation. Communicating with both the patient and his partner in a discreet, non-judgmental manner that fosters the physician-patient alliance can facilitate the recognition and treatment of ED.

Tratamiento con doxazosina en 3.347 pacientes con síntomas del tracto urinario inferior. efecto sobre su función sexual. estudio impros

OBJECTIVES

An open, non-comparative, multicenter study was performed to ascertain the prevalence in Spain of erectile dysfunction (ED) associated to benign prostatic hypertrophy (BPH), with moderate to severe urinary symptoms, and to confirm the improvement or disappearance of ED in response to treatment with 4 mg/day of Doxazosin.

METHODS

Out of the 3901 patients recruited 3545 took the medication and 3347 completed all the protocol visits. BPH patients were considered to have some degree of erectile dysfunction when they reported a difficulty for obtaining and/or maintaining an erection in the four weeks prior to their inclusion in the study (questions 3 and 4 of the International Index of Erectile Function). All the patients were treated with Doxazosin at increasing doses: from 1 mg/day up to 4 mg/day thereafter until 6 months of medication were completed.

RESULTS

The mean number of patients showing erectile dysfunction was 69.1%, ranging from 48.3% in the 40-49 years age group to 76.3% in the group aged from 60 to 69 years. In most Spanish regions, the prevalence of ED ranged from 76.9% in Cantabria to 67.2% in Aragon. The mean number of patients in whom erectile dysfunction disappeared after treatment, with a 95% confidence interval, was 4.5%, ranging from 17.5% in the 40-49 age group to 1.1% in the over 70s.

CONCLUSIONS

ED is a symptom very often associated to BPH, even in relatively young men. Doxazosin appears to have a beneficial effect in ED improvement, particularly in the younger patients.

Implications of diabetes mellitus in urology

The incidence of DM is rapidly growing among Americans. DM will rival cancer and heart disease in terms of cost and suffering. The National Institute of Health is tripling the research dollars that are spent on diabetic-related research in an attempt to combat this disease. Urologists are on the front line in the diagnosis and treatment of the complications of DM. The complications of DM that we reviewed in this article, diabetic cystopathy and diabetic ED, can occur in the early stage of DM and often progress in a silent fashion. More awareness and interest are needed to improve our understanding of diabetic complications in urology. Exciting new approaches in the treatment of diabetic cystopathy and ED are being investigated.

Simultaneous identification/determination system for phentolamine and sildenafil as adulterants in soft drinks advertising roborant nutrition

An easily available, simultaneous identification/determination procedure for phentolamine (PHE) and sildenafil (SIL) in adulterated dietary supplements was established by using a combination of three different analytical methods; thin-layer chromatography (TLC), liquid chromatography-mass spectrometry (LC/MS) and a high-performance liquid chromatography (HPLC)/photo-diode-array. The sample solution for TLC was applied to silica gel 60 F(254) plates with chloroform/ammonia solution (28)/methanol (70:5:3, lower layer) and chloroform/diethylamine/methanol (15:3:2) as the developing solvent. Spots were located under UV radiation at 254 nm. Mass spectra of PHE and SIL by LC/MS were investigated with electrospray ionization (ESI) interface, under both positive and negative ion mode. The HPLC analysis was performed on a column of Wakosil 5C18 (4.6 mm x 150 mm, 5 microm) with water/methanol/acetonitrile/triethylamine (580:250:170:1) adjusted with phosphoric acid to pH 3.0 as the mobile phase, and the effluent was monitored with a photo-diode-array detector. Quantitative HPLC analysis of PHE and SIL were detected at 280 nm. When this procedure was applied to commercial soft drinks, PHE and SIL were identified and determined at a concentration of 17 mg PHE and 44 mg SIL per bottle, respectively. The procedure described here is available for the screening of PHE and SIL in adulterated supplements.

Long-term safety and efficacy of oral phentolamine mesylate (Vasomax) in men with mild to moderate erectile dysfunction

The objectives of this study were to evaluate long-term safety and efficacy of phentolamine mesylate, an orally active, rapid-acting alpha-adrenergic receptor antagonist, for the treatment of men suffering from erectile dysfunction (ED). It was an open-label study involving more than 2000 patients. Men received phentolamine mesylate 40 mg or 80 mg (10 tablets/month) as needed for up to 13 months and self-assessed erectile performance using two validated questionnaires. Treatment with phentolamine mesylate was associated with increases in Erectile Function Domain score of the IIEF, successful vaginal penetrations, and in overall satisfaction. Most adverse events were mild or moderate in severity and consistent with the known pharmacodynamic properties of phentolamine. In conclusion, phentolamine mesylate is safe and effective in the long-term treatment of men with mild to moderate ED.

Enhancement of apomorphine-induced penile erection in the rat by a selective alpha(1D)-adrenoceptor antagonist

1. Effects of A-322312 (alpha(1B)-adrenoceptor (AR) antagonist), A-119637 (alpha(1D)-AR antagonist), prazosin (non-selective alpha(1)-AR antagonist), and yohimbine (alpha(2)-AR antagonist) were studied in rat corpus cavernosum (CC) and cavernous artery (Acc) preparations. Effects of intracavernous (i.c.) or intraperitoneal (i.p.) administration of alpha(1)-AR antagonists on apomorphine-induced erections were investigated. 2. A-119637 attenuated electrically induced contractions in isolated CC (-logIC(50); 8.12+/-0.15), and relaxed noradrenaline (NA)-contracted preparations by more than 90% at 10(-7) M. At the same concentration, the -logEC(50) value for NA in Acc was altered from 6.79+/-0.07 to 4.86+/-0.13. In the CC and Acc, prazosin similarly inhibited contractile responses. 3. Inhibitory effects of A-322312 (10(-7) M) in electrically activated CC were 32.3+/-5.1%, whereas no effect on concentration-response curves for NA was observed in the Acc. Yohimbine (10(-8) M and 10(-7) M), enhanced electrically-induced contractions in isolated CC by 20 to 50%. At 10(-6) M, inhibitory effects of yohimbine were obtained. 4. A-119637 (0.3 micromol kg(-1), i.p.) tripled the number of erections, and produced a 6 fold increase in the duration of apomorphine-induced erectile responses. A-322312, prazosin, or yohimbine did not enhance erections induced by apomorphine. None of the alpha(1)-AR antagonists significantly increased ICP upon i.c. administration. Decreases in blood pressure were seen with A-119637 and prazosin. 5. The present findings show that there is a functional predominance of the alpha(1D)-AR subtype in the rat erectile tissue, and that blockade of this receptor facilitates rat penile erection induced by a suboptimal dose of apomorphine.

Pharmacological aspects of erectile dysfunction

Erectile dysfunction (ED) is a common problem with a prevalence of approximately 50% in men aged 40 to 70. There are several etiologies for ED including vasculogenic, neurogenic, hormonal and/or psychogenic factors; one-fourth of ED cases can be drug-related. Penile erection involves a complex interaction between the CNS and local factors. It is a neurovascular event modulated by psychological and hormonal factors. Pharmacologically, neural modulation and endocrine status are very important to attaining penile erection. There have been several significant advances for the pharmacologic treatment of ED. Treatments include agents that are not only orally effective, but possess either local or central acting mechanisms of action. Apomorphine, a centrally-acting agent, is effective in the treatment of ED. Sildenafil, another orally effective agent, acts by inhibiting cyclic GMP-specific phosphodiesterase Type V. Testosterone can be effective transdermally. Non-orally active agents include alprostadil and papaverine. Phentolamine and trazodone are effective in selected cases. Some agents can interact with other medications. Several pharmacological agents, some with central-acting mechanisms and some with Iocally-acting vascular effects, are therapeutically useful in the treatment of ED.

Evaluation and treatment of erectile dysfunction in men with diabetes mellitus

Diabetic men have a more than 3-fold increased prevalence of erectile dysfunction (ED) compared with nondiabetic men. Erectile function is primarily a vascular phenomenon, triggered by neurologic controls and facilitated by appropriate hormonal and psychological components. Recent advances in the understanding of the physiology of penile vasculature and its role in male sexual performance have influenced the clinical approach to ED. The pathophysiological alterations leading to impotence in diabetic men include vasculogenic, neurogenic, and hormonal etiologies. A clinical work-up, including a thorough history and physical examination, is an important aspect of ED management. Biochemical evaluations to rule out secondary causes like hypogonadism and thyroid abnormalities are suggested. Oral medications acting through phosphodiesterase inhibition in penile vasculature have revolutionized treatment of impotence in diabetic men. Because of a high success rate in treating ED of various etiologies, these agents are the treatment of choice for most patients. Safety and efficacy of vacuum-constriction devices, intraurethral suppositories, intracavernosal injections, and other therapies are discussed. A clinical algorithm for the evaluation and management of ED is provided for use in the primary care setting.

Combined oral therapy with sildenafil and doxazosin for the treatment of non-organic erectile dysfunction refractory to sildenafil monotherapy

The purpose of this work was to investigate the efficacy and safety of sildenafil in combination with doxazosin for the treatment of non-organic erectile dysfunction in patients who did not respond to sildenafil. We enrolled 28 patients with non-organic erectile dysfunction, for whom 3 months of sildenafil monotherapy had failed. They were divided in two random and homogeneous groups: 14 were treated with doxazosin (4 mg daily) and sildenafil (100 mg 1 h before sexual intercourse); the other 14 patients received sildenafil and placebo. The results were assessed by means of the IIEF questionnaire before the beginning of the study, after 30 days of therapy and after 60 days. Of the 14 patients treated with doxazosin and sildenafil, 11 (78.6%) showed a statistically significant increase of IIEF; in the placebo group, only one patient (7.1%) recorded a significant IIEF increase. The differences observed in the two groups were statistically very significant (P=0.0016). Blood pressure did not show significant alterations. Side effects were minimal and even present during sildenafil monotherapy. The combination therapy with sildenafil and doxazosin resulted in the safe and effective treatment of men with non-organic erectile dysfunction for whom sildenafil alone had failed.

Cavernous and systemic plasma levels of norepinephrine and epinephrine during different penile conditions in healthy men and patients with erectile dysfunction

OBJECTIVES

To examine and compare the courses of norepinephrine (NE) and epinephrine (E) plasma levels in the systemic and cavernous blood taken during different penile conditions from healthy men and a group of patients with erectile dysfunction (ED). Knowledge concerning the neurophysiology of penile erection has improved tremendously during the past two decades. However, only few in vivo studies on human peripheral neurotransmission have been carried out to date.

METHODS

Fifty-three healthy adult male subjects and 47 patients with ED of different etiologies were exposed to erotic stimuli to elicit penile tumescence and, in the group of healthy subjects, rigidity. Whole blood was simultaneously aspirated from the corpus cavernosum and the cubital vein during different penile conditions. Plasma levels of NE and E were determined by means of a radioimmunoassay.

RESULTS

In the healthy subjects, a significant reduction of NE in cavernous plasma was detected from flaccidity (362 +/- 173 pg/mL) to rigidity (248 +/- 122 pg/mL), followed by an increase in the detumescence phase (336 +/- 199 pg/mL). Changes in NE levels in the peripheral plasma were less pronounced. Cavernous E levels significantly increased from flaccidity (47 +/- 41 pg/mL) to tumescence (130 +/- 106 pg/mL) and dropped from rigidity (113 +/- 67 pg/mL) to detumescence (76 +/- 57 pg/mL). The course of systemic E plasma levels was similar to that in the cavernous blood. In contrast, median NE levels in the systemic and cavernous blood of the ED group slightly increased from flaccidity to tumescence (from 199 +/- 88 pg/mL to 210 +/- 99 pg/mL and from 273 +/- 140 pg/mL to 278 +/- 118 pg/mL, respectively).

CONCLUSIONS

In healthy men, penile erection is accompanied by a reduction of NE in the cavernous blood and a rise in E levels in the peripheral and cavernous blood. That NE levels in the cavernous and systemic blood increase during sexual arousal in patients with ED might be an indication of a somatic dysregulation in sympathetic transmission or alterations of NE reuptake mechanisms as a cause of impaired erectile function.

A risk-benefit assessment of sildenafil in the treatment of erectile dysfunction

Sildenafil is an oral treatment for erectile dysfunction (ED). It acts as an inhibitor of 3',5'-cyclic guanosine monophosphate-phosphodiesterase type 5. An effective treatment for ED is required to produce an erectile response sufficient for satisfactory sexual performance. This has been documented for sildenafil in men with ED of differing aetiologies and baseline severity in various types of clinical trials. Sildenafil treatment is characterised by a good tolerability profile and low treatment digcontinuation rate caused by treatment-related adverse effects. Most of the adverse effects associated with sildenafil are extensions of the pharmacological action of the drug. There is no significant difference in the adverse effect profile (headache, flushing, dyspepsia, nasal congestion and abnormal vision) of this agent as assessed by clinical data obtained either in the pre- and postlaunch periods. Because of its acceptable risk-benefit ratio, sildenafil can be prescribed to a very large group of patients with ED. The reports of serious cardiovascular events associated with the use of sildenafil (including anecdotal reports of deaths) have been very thoroughly analysed. A number of studies have not shown any difference in the risk of serious cardiovascular events in sildenafil- and placebo-treated patients. However, when making a risk-benefit evaluation, certain subgroups of patients need to be considered separately. In particular, sildenafil is contraindicated in patients receiving nitrate therapy. In some other subgroups of patients, the risks and benefits of treatment need to be assessed on an individual basis and it is hoped that additional data will clarify any possible risks associated with sildenafil administration such patients. It is helpful to compare the risk-benefit profile of sildenafil with the characteristics of other oral drugs for ED. According to the preliminary data, apomorphine and phentolamine are possible future options for the treatment of ED; however, there needs to be further clinical evaluation of these agents. Initial data have shown that sildenafil can be successfully combined with intracavernosal injection in patients nonresponders to either therapy. In conclusion, favourable characteristics make sildenafil suitable for the first-line therapy for a substantial proportion of patients with ED.

ASSESS-3: a randomised, double-blind, flexible-dose clinical trial of the efficacy and safety of oral sildenafil in the treatment of men with erectile dysfunction in Taiwan

The efficacy and safety of sildenafil were evaluated in a randomised, double-blind, placebo-controlled, flexible-dose study in Taiwanese men aged 26 to 80 y with erectile dysfunction (ED) of broad-spectrum aetiology and more than 6 months' duration. A total of 236 patients were randomised at six medical centres in Taiwan to receive either sildenafil (50 mg initially increased if necessary to 100 mg or decreased to 25 mg depending on efficacy and toleration) (n=119) or matching placebo (n=117) taken on an 'as needed' basis 1 h prior to anticipated sexual activity for a period of 12 weeks. At the end of 12 weeks, the primary efficacy variables relating to the achievement and maintenance of erections sufficient for sexual intercourse, and the secondary efficacy variables, which included: (1) the five separate domains of sexual functioning of the IIEF (International Index of Erectile Function) scale, (2) the percentage of successful intercourse attempts; and (3) a global assessment of erections, were all statistically significantly improved by sildenafil in comparison with placebo (P<0.0001). Treatment-related adverse events occurred in 43.7% of patients receiving sildenafil and 18.8% receiving placebo. The most common adverse events with sildenafil were flushing, dizziness and headache (25.2, 6.7 and 5.9% of patients, respectively), and most were mild in nature. The efficacy and safety of sildenafil in the population of Taiwanese men appears similar to that reported in other studies in western populations.

A conscious-rabbit model to study vardenafil hydrochloride and other agents that influence penile erection

Experimental models to study the effect of agents on penile erection usually include electrical stimulation of peripheral nerves in anesthetized animals combined with systemic or intracavernous injection of drugs. The objective of this study was to demonstrate that conscious rabbits can be used as a simple and quantitative model for the assessment of compounds that show potential for the treatment of erectile dysfunction. Erection was assessed by measuring the length of uncovered penile mucosa before and after the intravenous (i.v.) administration of agents. Animals did not require anesthesia during the course of the study. The phosphodiesterase 5 (PDE5) inhibitors vardenafil x HCl (hereafter called vardenafil) and sildenafil were given intravenously, and measurements were taken for 0-5 h. The effects of phentolamine and milrinone were also evaluated. Vardenafil (0.1-3 mg/kg) induced dose-dependent penile erections in conscious rabbits following i.v. administration. The efficacy of vardenafil was potentiated, and the minimal effective dose was reduced significantly to 0.01 mg/kg by simultaneous administration of the nitric oxide (NO) donor sodium nitroprusside (SNP). Administration of the NO-synthase inhibitor L-NAME abolished the effect. Sildenafil was effective in this model after i.v. administration. The alpha-adrenergic receptor antagonist phentolamine (0.1, 0.3 and 1 mg/kg i.v.) induced erections with a slower t(max) compared with vardenafil and sildenafil. Intravenous administration of the PDE3 inhibitor milrinone (1 mg/kg i.v.) was less effective than the PDE5 inhibitor vardenafil. The conscious rabbit is a suitable and reliable model for the evaluation of compounds with potential for the treatment of erectile dysfunction. This was demonstrated using compounds that target different signaling pathways that induce smooth muscle relaxation in the penis.

Intracavernous injections: still the gold standard for treatment of erectile dysfunction in elderly men

The objective of this work was to determine the effectiveness of intracavernous injections (ICI) of vasoactive drugs in elderly men with erectile dysfunction and to compare the results obtained with the injection of two different drug combinations. It was a case control study. The sample consisted of 300 men, 63-85 y of age (mean 67.1) with erectile dysfunction of organic origin. Among the patients 180 underwent first trial with injection of prostaglandin E1 (PE). Further on these 180 patients and another 120 (in total 300 patients) were treated with a triple combination of papaverine hydrochlorate, phentolamine messylate and prostaglandin E1 (PPR). The number of responders to the injection of either PE alone or the drug combination was recorded. The quality of the erections was evaluated in the outpatient clinic by the medical staff and through patient's report after home trial. The average volume of either PE or PPR necessary to obtain a functional erection was measured. We observed a statistically significant association between the results obtained after the injection of PPR as compared to PE (chi2 with 2 d.f.: 34.666; P= < 0.001). A functional erection was obtained in 224/300 (74.7%) after the injection of PPR as compared to 87/180 men (48.3%) treated with PE. The average volume of PPR necessary to obtain a functional erection was 0.35+/-0.14 ml whereas that of PE was 1.3+/-0.3 ml. intracavernous injection of vasoactive drugs is still one of the most successful therapies for patients suffering from organic impotence. It is less effective in the older age group as compared to younger. However, if this form of therapy is chosen for aged men the triple combination therapy (PPR) yields a higher response rate than that obtained with prostaglandin alone.

Evaluation of oral ro70-0004/003, an alpha1A-adrenoceptor antagonist, in the treatment of male erectile dysfunction

Alpha-adrenoceptor antagonists have been used for the treatment of male erectile dysfunction (MED). Ro70-0004/003 (Ro70-0004) is a selective and orally active alpha1A-adrenoceptor antagonist. The objective of this study was to: (1) pharmacologically elucidate the alpha1-adrenoceptor subtype mediating norepinephrine-induced contraction of human isolated corpus cavernosal tissue and (2) conduct a clinical proof-of-concept study with Ro70-0004 to test the hypothesis that selective alpha1A-adrenoceptor blockade would improve erectile function in patients with MED. In vitro organ bath studies were conducted with strips of human isolated corpus cavernosal tissue obtained from patients undergoing penile prosthesis implantation. Prazosin, cyclazosin, RS-100329 and Ro70-0004/003 antagonized norepinephrine-induced contractile responses with affinity estimates (pK(B) or pA2) of 8.4, 7.3, 9.2 and 8.8, respectively, consistent with the singular involvement of alpha1A-adrenoceptor subtype. A clinical study (single center, observer-blind, randomized, placebo-controlled, extended period Latin-Square crossover design) was conducted in 24 male patients (mean age 44 y) with MED of no established organic cause to evaluate the efficacy of a 5-mg oral dose of Ro70-0004. The primary efficacy endpoint was the duration of rigidity > 60% at the base of the penis measured between 0.5 and 2.5 h post-dose. Rigidity was assessed by penile plethysmography using the RigiScan Plus device during visual sexual stimulation. The safety and efficacy of Ro70-0004 was also assessed. A 50-mg dose of sildenafil was included as a positive control. For the primary efficacy endpoint, the mean duration of erection was 9.69 min following administration of placebo, 8.28 min following Ro70-0004, and 22.64 min following sildenafil. Only the difference between sildenafil and placebo reached statistical significance (P < 0.05). A similar pattern was observed when measuring a duration of rigidity > 80% at the base of the penis (secondary endpoint). Ro70-0004 was safe and generally well tolerated (only two out of 20 patients reported at least one adverse event). The highly selective alpha1A-adrenoceptor antagonist, Ro70-0004, given at a single dose of 5 mg, did not improve erectile function when compared to placebo.

Combination of phentolamine and L-arginine or sildenafil synergistically improves neurogenic relaxation of rabbit corpus cavernosum smooth muscle

OBJECTIVES

To analyze the effects of combining an alpha-adrenergic receptor antagonist, phentolamine, with an enhancer of the nitric oxide/cyclic guanosine monophosphate pathway (L-arginine or sildenafil) on neurogenic relaxations of rabbit corpus cavernosum (RCC).

METHODS

Studies were performed on isolated RCC tissue in organ chambers. Transmural electrical stimulation (TES) was applied at increasing frequencies (0.5 to 6 Hz) on endothelin-contracted RCC strips, and the responses were evaluated.

RESULTS

The activation of alpha(2)-adrenergic receptors with UK 14304 (0.3 microM) significantly inhibited the relaxation induced by TES in RCC strips in which adrenergic neurotransmission was blocked with guanethidine (10 microM). The relaxant responses produced by TES application on RCC strips without guanethidine were not significantly affected by the treatment with L-arginine or sildenafil but were significantly augmented by phentolamine (2.7-fold increase in maximum relaxation). Furthermore, the combinations of phentolamine with L-arginine or sildenafil markedly increased the relaxations evoked by the application of TES in RCC tissue, significantly more than those obtained in the presence of phentolamine alone (4.5 or 4.7-fold increase of maximum relaxation, respectively).

CONCLUSIONS

Our results demonstrated a synergistic interaction between the alpha-adrenergic blockade and the potentiation of the nitric oxide/cyclic guanosine monophosphate pathway to increase neurogenic relaxation of trabecular smooth muscle relaxation. This fact suggests that the combination of alpha-adrenergic receptor blockade with L-arginine or sildenafil could represent a therapeutic advantage in the treatment of erectile dysfunction.

Phentolamine mesylate relaxes rabbit corpus cavernosum by a nonadrenergic, noncholinergic mechanism

The contribution of NO-cGMP dependent pathway to phentolamine mesylate-evoked nonadrenergic, noncholinergic relaxation of rabbit corpus cavernosum was investigated in vitro. Stimulation of nonadrenergic, noncholinergic neurons of the rabbit corpus cavernosum elicited frequency-related relaxation that was significantly attenuated by L-NAME (NO synthase inhibitor) or ODQ (an inhibitor of guanylate cyclase). Moreover, tetrodotoxin, a sodium channel blocker, abolished the electrical field stimulation-induced relaxation of rabbit corpus cavernosum, suggesting that neuronal release of NO mediates relaxation to electrical field stimulation. Phentolamine mesylate (30 and 100 nM) dose-dependently enhanced electrical field stimulation-induced relaxation of the rabbit corpus cavernosum. Prazosin (30 microM) and yohimbine (30 microM) failed to affect phentolamine mesylate-mediated nonadrenergic, noncholinergic rabbit penile smooth muscle relaxation, suggesting that phentolamine relaxes rabbit corpus cavernosum independent of alpha-adrenergic receptor blockade. In contrast, pretreatment of the rabbit cavernosal strips with L-NAME significantly-attenuated electrical field stimulation produced relaxations to phentolamine mesylate, suggesting that phentolamine mesylate relaxes rabbit corpus cavernosum by activating NO synthase. The data suggest that phentolamine mesylate relaxes nonadrenergic noncholinergic neurons of the rabbit corpus cavernosum by activating NO synthase and is independent of alpha-adrenergic receptor blockade.

Non-surgical management of erectile dysfunction

Erectile dysfunction is a common and distressing medical condition that is now highly amenable to treatment almost irrespective of the cause. Safe, non-surgical treatments with unequivocal efficacy are psychological therapy, intracorporeal injection of vasoactive drugs, transurethral vasodilators and oral sildenafil, all of which have been reported to have a 50-70% overall response rate. Vacuum constriction devices are acceptable for some, usually older patients and oral yohimbine is thought to have marginal efficacy. Local creams to induce or enhance erectile function are currently being investigated. There is no place for androgen supplementation unless the patient is profoundly hypogonadal. Treatment of hyperprolactinaemia is very effective but is a rare cause of erectile dysfunction. As intercourse may entail an unfamiliar level of physical activity, it is sensible to ensure that the patient is able to climb a flight or two of stairs comfortably without provoking undue breathlessness or chest pain and to provide suitable advice about technique before commencing treatment. Once it is clear to the patients that erectile dysfunction can be satisfactorily overcome, the long-term use of treatments to do so tends to wane. Thus, although the prospect of effective treatment for what had been for many a distressing life sentence has the potential to place new demands on the health service, there is no evidence that restrictions on prescribing will prove economically rational.

Physiology and pathophysiology of erection: consequences for present medical therapy of erectile dysfunction

Smooth muscle relaxation of the corpus cavernosum is the key mechanism of erection. It depends on a cascade of consecutive regulatory systems starting in the central nervous system, and proceeding via peripheral neurotransmission to intracellular signal transmission within the cavernous smooth muscle cells. Knowledge of these interacting mechanisms of erection is fundamental for understanding of the mode of action of new and possibly selective pharmacological agents that are presently available or under evaluation for treatment of erectile dysfunction.

Lack of sexual activity from erectile dysfunction is associated with a reversible reduction in serum testosterone

The role of androgenic hormones in human sexuality, in the mechanism of erection and in the pathogenesis of impotence is under debate. While the use of testosterone is common in the clinical therapy of male erectile dysfunction, hypogonadism is a rare cause of impotence. We evaluated serum testosterone levels in men with erectile dysfunction resulting either from organic or non-organic causes before and after non-hormonal impotence therapy. Eighty-three consecutive cases of impotence (70% organic, 30% non-organic, vascular aetiology being the most frequent) were subjected to hormonal screening before and after various psychological, medical (prostaglandin E1, yohimbine) or mechanical therapies (vascular surgery, penile prostheses, vacuum devices). Thirty age-matched healthy men served as a control group. Compared to controls, patients with impotence resulting from both organic and non-organic causes showed reduced serum levels of both total testosterone (11.1 +/- 2.4 vs. 17.7 +/- 5.5 nmol/L) and free testosterone (56.2 +/- 22.9 vs. 79.4 +/- 27.0 pmol/L) (both p < 0.001). Irrespective of the different aetiologies and of the various impotence therapies, a dramatic increase in serum total and free testosterone levels (15.6 +/- 4.2 nmol/L and 73.8 +/- 22.5 pmol/L, respectively) was observed in patients who achieved normal sexual activity 3 months after commencing therapy (p < 0.001). On the contrary, serum testosterone levels did not change in patients in whom therapies were ineffective. Since the pre-therapy low testosterone levels were independent of the aetiology of impotence, we hypothesize that this hormonal pattern is related to the loss of sexual activity, as demonstrated by its normalization with the resumption of coital activity after different therapies. The corollary is that sexual activity may feed itself throughout the increase in testosterone levels.

Male impotence

Erectile dysfunction can be devastating for men and for their partners. A good sexual history and focused physical examination can provide clues as to whether the underlying cause is psychogenic or organic. Diagnostic investigation should be tailored to the clinical picture. Oral medications now represent first-line therapy. Penile injection therapy and vacuum constrictive devices are reasonable choices for men in whom oral therapy falls or is contraindicated. The penile prosthesis provides a reliable long-term solution with high satisfaction rates. Psychotherapy may be indicated. Physicians can have a positive impact on the quality of life of patients by providing a non-judgmental and supportive environment for discussion and management of impotence.

Pharmacological treatment of erectile dysfunction

There is growing evidence that the field of pharmacotherapy, particularly oral drugs, will be dominant in the future management of sexual dysfunction. Basic research has led to the understanding of the intracellular mechanisms that control penile smooth muscle contractility and therefore erection, opening a vast area for pharmacological intervention. Moreover, the importance of central neurohormonal mechanisms has made these pathways the target for new centrally acting drugs. Given these trends most patients suffering from erectile dysfunction will respond to pharmacological agents in the not so distant future.

Erectile dysfunction in patients with diabetes

Erectile dysfunction, which is common among men with diabetes, leads to significant reduction in quality of life, and as with other complications of diabetes deserves to be treated on the NHS. This article explores the problem of erectile dysfunction and diabetes and the role of sildenafil, which is likely to be the first choice treatment of patients presenting with erectile dysfunction.

Pharmacotherapeutic advances in the treatment of erectile dysfunction

An estimated 20 million to 30 million American men have erectile dysfunction (ED). The past 2 decades of research defining erectile physiology and investigating the pathogenesis of ED have led to the recognition of a predominantly vascular basis for organic male sexual dysfunction. These scientific advances have laid the foundation for the advent of pharmacotherapies. The Food and Drug Administration approval of intracavernosal, intraurethral, and oral pharmacotherapeutics for ED has revolutionized non-surgical management of this condition. The primary care physician is faced with the challenges of diagnosis and treatment of ED, as well as referral of patients to urologists. In this article, erectile physiology and pathophysiology are reviewed, and pharmacotherapeutics are classified and discussed by their mechanisms of action and the means of administration. A thorough understanding of these new therapeutic options is key to the accurate diagnosis and successful treatment of ED and maximal patient satisfaction and care.

Assessment and management of erectile dysfunction in men with diabetes

PURPOSE

Erectile dysfunction occurs earlier in men with diabetes than in the general population, affecting over 50% of male patients by age 60. This article summarizes the etiologies and presents methods of patient assessment and treatment options for erectile dysfunction.

METHODS

Assessments of neurologic and vascular complications related to diabetes should be included in a sexual function history. The assessment must be holistic and focus on organic as well as psychogenic causes. Diabetes educators must be prepared to discuss the various pharmacologic treatment options.

RESULTS

Sildenafil currently is the only oral medication available for erectile dysfunction. Injectable treatments have proven successful but with limited long-term use and poor patient acceptance. Implantable devices carry surgical risk and increased rates of infection.

CONCLUSIONS

All men with diabetes should be screened for erectile dysfunction. The availability of a new oral medication provides a patient-acceptable treatment option.