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...

Vardenafil and sildenafil are potent and specific phosphodiesterase type 5 (PDE 5) inhibitors. In human penile cavernosal smooth muscle cells, we have previously shown that vardenafil has a lower biochemical inhibition constant (Ki) than sildenafil. In this study, we compared the efficacy of vardenafil and sildenafil in facilitating penile erection in a rabbit model. Penile erections were elici...

BACKGROUND Pregnancies with early onset fetal growth restriction have poor perinatal outcome. Sildenafil citrate (PDE -5 inhibitor) as a vasodilator increases utero-placental blood flow and potentiates fetal growth. CASE PRESENTATION In this study, a case was examined and Sildenafil was administered for her. It was found that Sildenafil improved the uterine blood flow with a favorable fetal o...

BACKGROUND The double-blind, placebo-controlled Sildenafil in Treatment-Naive Children, Aged 1 to 17 Years, With Pulmonary Arterial Hypertension (STARTS-1) study assessed sildenafil in pediatric patients with pulmonary arterial hypertension; improved hemodynamics and exercise capacity occurred in medium- and high-dose groups. STARTS-2 was the extension study. METHODS AND RESULTS In STARTS-1, ...

The present studies focused on the ability of the phosphodiesterase 5 (PDE5) inhibitor sildenafil to enhance the anti-cancer properties of clinically relevant concentrations of the dietary diarylheptanoid curcumin. In gastrointestinal tumor cells, sildenafil and curcumin interacted in a greater than additive fashion to kill. Inhibition of the extrinsic apoptotic pathway suppressed killing by ∼5...

INTRODUCTION Pulmonary hypertension is a progressive disease of diverse origin with devastating consequences in adults as well as in children. The phosphodiesterase 5 inhibitor sildenafil successfully lowers pulmonary vascular resistance. However, because of its poor enteral absorption, resulting in ineffective plasma concentrations, responses in infants and children are often erratic. CASE P...