INTRODUCTION Viagra (sildenafil citrate) has a rapid onset of action for the treatment of erectile dysfunction (ED). However, its duration of action has not been thoroughly investigated. Practical knowledge of the time window available for sexual intercourse would be valuable for couples planning sexual activity. AIM We investigated the duration of action of sildenafil in men with ED. METHO...

Background: Sildenafil causes vasodilatation by relaxing the smooth muscles of blood vessels. This enhances endometrial development, the health of which is indispensable for implantation and embryonic and fetal development. Aim: To assess the role of Sildenafil when used in ovulation induction cycles with Clomiphene Citrate (CC) with reference to Endometrial Thickness (ET), follicular developme...

BACKGROUND Sildenafil, a phosphodiestase type 5 inhibitor, was approved in 2005 for the treatment of pulmonary arterial hypertension (PAH) in adults and is commonly used off-label for pediatric patients. Little is known, however, about sildenafil's side effects in this population. METHODS Single institution, longitudinal survey-based study performed in an outpatient pediatric cardiology clini...

BACKGROUND Erectile dysfunction (ED) is common in men with renal failure, but is not always alleviated following kidney transplant. The objective of the present study was to assess the feasibility in renal transplant patients of sildenafil citrate treatment, an agent with proven efficacy in the management of ED. METHODS This was a phase IV, open, multicentre, 3 month, dose-escalation study. A...

In this study, the effects of sildenafil administration on penile erection and semen volume and characteristics in Kangal dogs were studied. A total of 5 Kangal dogs, aging 3-6 years, and with a known fertility were used. In each application, sildenafil was administered orally at a dosage of 50 mg, 60 minutes prior to semen collection. Semen was collected 12 times at 3-day intervals by digital ...

Pharmacokinetics of sildenafil and its metabolite, N-desmethylsildenafil, in humans and rats with liver cirrhosis (LC) and diabetes mellitus (DM), alone and in combination (LCD) did not seem to be reported. Sildenafil was administered intravenously (10 mg/kg) and orally (20 mg/kg) to control, LC, DM, and LCD rats. Expression of intestinal CYP isozymes in those rats was also measured. In LC, DM,...

Sildenafil citrate (Viagra), a cGMP-selective phosphodiesterase (PDE) inhibitor, is widely used to treat erectile dysfunction and pulmonary arterial hypertension. In contrast to its well established action on erectile dysfunction, little is known on the action of sildenafil on cGMP/cAMP signaling and testicular steroidogenesis. This study was designed to assess the effects of prolonged sildenaf...

OBJECTIVE We studied the effects of sildenafil, a phosphodiesterase 5 inhibitor, on coronary and peripheral vascular function, platelet activation, and myocardial ischemia. BACKGROUND Nitric oxide vasodilates and inhibits platelet activation by generating cyclic guanosine 5'-monophosphate, which is metabolized by phosphodiesterase type 5. METHODS The effect of oral sildenafil on resting cor...

BACKGROUND Sildenafil is a potent inhibitor of cyclic guanosine monophosphate hydrolysis [corrected] in the corpus cavernosum and therefore increases the penile response to sexual stimulation. We evaluated the efficacy and safety of sildenafil, administered as needed in two sequential double-blind studies of men with erectile dysfunction of organic, psychogenic, and mixed causes. METHODS In a...

Sildenafil is the first marketed phosphodiesterase 5 inhibitor for the treatment of erectile dysfunction and recently, for pulmonary hypertension. While the treatment was found to be highly effective, several adverse effects are associated with this compound. Among numerous central nervous system-related untoward effects, proconvulsant activity was reported. The purpose of this study was to ass...