Sildenafil test: changes in the diagnostic and therapeutic management of Erectile Dysfunction.

OBJECTIVE: To assess the efficacy ofSildenafil Citrate (Viagra) as a first-step diagnostic and therapeutic tool for Erectile Dysfunction (ED) and to evaluate the consequent changes in the management of male sexual insufficiency. MATERIALS AND METHODS:Sildenafil Citrate (Viagra) in titrating doses up to 100 mg was prescribed to 50 men presenting to a sexual dysfunction clinic with medically documented ED. They had not undergone any specific diagnostic test before starting sildenafil. RESULTS: Of the 50 men, 24 (48%) responded to sildenafil. Of these, 8 (33.3%) responded to 50 mg and 16 (66.7%) to 100 mg of sildenafil. Of the responders, 9 representing 18% of all studied men were discharged achieving spontaneous erections in a mean follow-up of 5.3 months. Men with no medical history, men with hypertension and men with mild coronary artery disease responded better. CONCLUSIONS: TheSildenafil Citrate (Viagra) test revealed that 48% of men responded to this therapy with no requirement for more invasive tests and that 18% of men required no further treatment at all. In addition this test reduced the overall cost of the diagnostic investigation. It is proposed that theSildenafil Citrate (Viagra) test should be used in cases with no significant medical history or in men with hypertension or mild coronary artery disease although almost all men with ED could be categorized as sildenafil-responders or sildenafil-resistant. It is also suggested that theSildenafil Citrate (Viagra) test would result in the ability for more men with ED to be managed exclusively in the primary care sector

Effect of vaginalSildenafil Citrate (Viagra) on the outcome of in vitro fertilization (IVF) after multiple IVF failures attributed to poor endometrial development.

OBJECTIVE: To evaluate the effects of vaginally administeredSildenafil Citrate (Viagra) on endometrial thickness and IVF outcome in a large cohort of infertile women with poor endometrial development. DESIGN: Retrospective cohort analysis. SETTING: Private practice setting. PATIENT(S): A cohort of 105 infertile women aged <40 years, with normal ovarian reserve and at least two consecutive prior IVF failures attributed to inadequate endometrial development. INTERVENTION(S): Patients underwent IVF using a long GnRH-a protocol with the addition ofSildenafil Citrate (Viagra) vaginal suppositories (25 mg, 4 times per day) for 3-10 days. MAIN OUTCOME MEASURE(S): Peak endometrial development, pregnancy, and implantation rates. RESULT(S): Of 105 patients, 73 (70%; Group A), attained an endometrial thickness of >/=9 mm, whereas 32 (30%; Group B) did not. Implantation and ongoing pregnancy rates were significantly higher for Group A (29% and 45%) than for Group B (2% and 0). Of 11 women in Group B who had embryos transferred in that cycle, only one conception occurred, which resulted in a miscarriage. In Group B, 59% of women had a history of endometritis, compared with 44% in Group A. CONCLUSION(S): Vaginal administration ofSildenafil Citrate (Viagra) enhanced endometrial development in 70% of patients studied. High implantation and ongoing pregnancy rates were achieved in a cohort with a poor prognosis for success. Previous endometritis may decrease the response toSildenafil Citrate (Viagra)

Identification of a new analogue ofSildenafil Citrate (Viagra) added illegally to a functional food marketed for penile Erectile Dysfunction.

A new analogue ofSildenafil Citrate (Viagra) was discovered to have been added illegally to a functional food marketed for penile Erectile Dysfunction. The structure of the analogue was established by various NMR spectroscopic techniques (including DEPT, COSY, TOCSY, HMQC, HMBC). Because of the addition of a methylene group to sildenafil, the main ingredient of Viagra(R), it was given the name homosildenafil, and this has never been reported previously. An analytical method using HPLC was proposed. Homosildenafil was added as a new inspection item and other foods have since been discovered to contain it

Determination ofSildenafil Citrate (Viagra) in medicines for Erectile Dysfunction by capillary electrophoresis

A method has been developed for the determination ofSildenafil Citrate (Viagra) in the medicines for Erectile Dysfunction by capillary electrophoresis. The samples were analyzed with 60 mmol/L NaH2PO4(pH 5.0) running buffer at 35 degrees C capillary temperature and 30 kV voltage. A linear calibration was obtained from 0.07 g/L to 1.05 g/L ofSildenafil Citrate (Viagra) (r = 0.9985) with the RSD of 4.7% for peak area, and the average recovery was 97.4%. The results were compared with those of HPLC, showing that the method is precise, simple and cost-effective, and can be used as a complementary method to HPLC

Risk factors in predicting a poor response to Sildenafil Citrate (Viagra) in elderly men with Erectile Dysfunction.

OBJECTIVE: To assess the clinical efficacy ofSildenafil Citrate (Viagra) and the potential predictors of poor response toSildenafil Citrate (Viagra) in elderly patients with Erectile Dysfunction (ED). PATIENTS AND METHODS: The study included 162 patients (aged > or = 60 years) treated withSildenafil Citrate (Viagra) for at least 8 weeks; all patients were evaluated with a history, physical examination, measurement of total testosterone and a pharmacological erection test. Sexual function before and 8 weeks after treatment was assessed using the self-administered International Index of Erectile Function (IIEF). Treatment was considered successful when the patient attained a higher grade on the erectile function (EF) domain score, and an affirmative response to the overall assessment question. Factors influencing treatment outcome were evaluated by univariate and multivariate statistical analysis. RESULTS: The overall efficacy withSildenafil Citrate (Viagra) was 47% (76/162). On univariate analysis, uncontrolled diabetes, current smoking, hypogonadism (<3 microg/L testosterone) and low pretreatment EF domain score (<17) were selected as predictors of a poor response. On multivariate logistic regression, a low pretreatment EF domain score was the strongest independent prognostic factor for a poor response (odds ratio 2.25, 95% confidence interval, 1.45-7.33), and this was followed by hypogonadism (1.89, 1.12-3.16) and current smoking (1.34, 1.04-3.52). CONCLUSION: In a real clinical setting,Sildenafil Citrate (Viagra) was effective for about half of the elderly men. The baseline EF domain score, hypogonadism and current smoking were significantly associated with failure of sildenafil. These results suggest that modifying reversible risk factors, e.g. stopping smoking and replacing testosterone, would be beneficial in augmenting the efficacy ofSildenafil Citrate (Viagra) in elderly men

Patterns of use ofSildenafil Citrate (Viagra) among commercially insured adults in the United States: 1998-2002.

Sildenafil is increasingly being marketed to younger healthcare consumers. The purpose of this study was to profileSildenafil Citrate (Viagra) use in commercially insured, adult beneficiaries. Annual ambulatory prescription claims data from 1998 to 2002, for a nationwide, random sample of over 5 million life-years of commercially insured adults (aged > or =18 y), were examined retrospectively. The overall prevalence ofSildenafil Citrate (Viagra) use increased from 0.8% (1998) to 1.4% (2002), an 84% increase. While the growth in use slowed in older males, use became more pronounced in younger males and females and decreased in older females. The fastest growing segment of users was found to be males aged 18-45 y. The proportion of users who had two or more claims for a medication that is suspected of inducing Erectile Dysfunction (ED) and/or a marker for a suspected ED-inducing disease decreased over the study period. Our findings suggest that use may increase among younger male and female patients and those without an underlying etiologic reason for use

Effects of Sildenafil Citrate (Viagra) combined with nitrate on the heart.

BACKGROUND: Sildenafil Citrate (Viagra) is indicated for the treatment of Erectile Dysfunction. Large and sudden decreases in systemic blood pressure were reported in a substantial number of patients taking Sildenafil Citrate (Viagra) combined with nitroglycerin. We studied the effect of Sildenafil Citrate (Viagra) on the relationship between changes in systemic blood pressure and coronary blood flow. METHODS AND RESULTS: Healthy male beagles were used to assess systemic blood pressure, pulmonary arterial pressure, and flow in the left circumflex artery (in which a critical stenosis was established) and left anterior descending coronary artery. After measurement of the hemodynamic variables, 2 mg/kg Sildenafil Citrate (Viagra) was administered via a nasogastric tube. Hemodynamic changes were monitored for 1 hour. Subsequently, the acute effect of nitrate combined with Sildenafil Citrate (Viagra) was studied by the bolus injection of 0.2 mg isosorbide dinitrate before and after Sildenafil Citrate (Viagra). Systemic blood and pulmonary arterial pressures and circumflex flow did not change during this study; however, left anterior descending coronary arterial flow increased from 16.0+/-5.8 to 24.6+/-8.7 mL/min 1 hour after administration of Sildenafil Citrate (Viagra). The prolongation of systemic blood pressure decrease and the circumflex flow decrement induced by isosorbide dinitrate after Sildenafil Citrate (Viagra) were significantly larger and longer than those before Sildenafil Citrate (Viagra). CONCLUSIONS: Sildenafil Citrate (Viagra) had the effect of vasodilation in a normal coronary artery; however, a combined effect with nitrate resulted in large and protracted decreases in systemic blood pressure and coronary blood flow in vessels with critical stenosis

Effects ofSildenafil Citrate (Viagra) on human penile blood vessels.

OBJECTIVES: To investigate the effects ofSildenafil Citrate (Viagra) on human penile blood vessels and evaluate the interaction ofSildenafil Citrate (Viagra) with neurogenic-mediated responses.Sildenafil Citrate (Viagra) is currently used in the treatment of Erectile Dysfunction. METHODS: Penile dorsal arteries and deep dorsal veins were obtained from 14 multiorgan donors. Vascular rings were suspended in organ bath chambers, and the isometric tension was recorded. We then studied the effects ofSildenafil Citrate (Viagra) on precontracted vessels and the neurogenic (noradrenergic and nitrergic) responses. RESULTS:Sildenafil Citrate (Viagra) (10(-9) to 3 x 10(-6) M) caused concentration-dependent relaxation and amplified the relaxation induced by sodium nitroprusside. Relaxation was unaffected by the inhibitor of nitric oxide synthase N(G)-monomethyl-L-arginine (10(-4) M). Compared with zaprinast,Sildenafil Citrate (Viagra) was 8 to 10 times more potent in terms of the median effective concentration (EC(50)) values. Electrical field stimulation of the vessels under resting tension caused frequency-dependent contractions that were attenuated in the presence of sildenafil. When penile vessels were contracted after blockade of norepinephrine release with guanethidine (10(-6) M), electrical stimulation induced frequency-dependent, nitric oxide-dependent relaxations that were enhanced by sildenafil. CONCLUSIONS: These results indicate that the relaxation of human penile arteries and veins induced bySildenafil Citrate (Viagra) involves inhibition of noradrenergic contraction, enhancement of neurogenic nitric oxide-mediated relaxation, and inhibition of smooth muscle contraction