Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018681 (headache)
 56,091 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Erectile dysfunction (ED) (impotence) is a widespread, age-related problem, which affects 52% of men between 40 and 70 years of age. It is classified as psychogenic, organic, or mixed psychogenic and organic. ED is not a problem only of men, because the relationship between partners can also be disturbed. Therefore, adequate treatment of ED is needed and the most convenient and simplest way is oral drug therapy. Sildenafil, phosphodiesterase-(PDE)-5-selective inhibitor has been the drug of choice for patients with ED since it has been launched in March 1998. The results of various studies have confirmed the efficacy of the drug in men with ED of various etiologies, as well as the positive effect of sildenafil on the quality of a partnership. The most frequent adverse effects documented with sildenafil usage are headache, flushes, dyspepsia, visual disturbances and nasal congestion/rhinitis. These adverse effects are dose-related, usually transient and mild, with low withdrawal rate. Several studies performed recently have shown that sildenafil is a safe and effective treatment of ED in patients with cardiovascular disease, who do not take nitrates or nitrate donors concomitantly. Other oral medications for ED include apomorphine, phentolamine, yohimbine, trazodone, testosterone and new PDE-5 inhibitors in Phase III clinical trials, such as vardenafil and tadalafil. It is obvious, according to recent data, that the concept of PDE-5 inhibition has a central position in oral pharmacotherapy of ED. However, larger clinical studies of efficacy and safety should be carried out using most of the other above-mentioned oral agents and these may also gain a place in the therapy of ED. There are no studies directly comparing sildenafil and other treatments of ED or assessing its role in combination with other therapies. According to the present knowledge, the quality of life, not only of patients but also of their sexual partners, will be improved significantly with sildenafil usage and this is an important precondition for overall health ofboth. Sildenafil is thus a highly effective peroral treatment for ED in patients without contraindications for its use, which can be considered as the firstline therapy with an acceptable risk-benefit ratio.
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PMID:Erectile dysfunction: oral pharmacotherapy options. 1235 56

The aim of this study was to evaluate the efficacy and safety of oral sildenafil to treat erectile dysfunction (ED) in chronic renal failure in patients on hemodialysis (HD). A double-blind, randomized, placebo-controlled study of oral sildenafil (50 mg) administered as required in HD patients with ED was designed. Patients on HD for at least 6 mo and who had a stable relationship with a female sexual partner were included. Patients older than 70 yr with penile anatomic abnormalities, cirrhosis, diabetes, angina, severe anemia, and those who were on nitrate treatment or with a recent history of stroke or myocardial infarction were not included. The International Index of Erectile Dysfunction (IIEF) was employed to evaluate ED and treatment response. Forty-one patients were evaluated (21 received placebo, and 20 sildenafil). Baseline clinical and demographic parameters were similar in both groups. Sildenafil was associated with improvement in the score of all questions and domains of the IIEF, except those related to sexual desire. Using the erectile function domain to evaluate primary efficacy, improvement was observed in 85% of the sildenafil patients compared with 9.5% of placebo patients. Sildenafil use resulted in normal EF scores in 35% of sildenafil patients. Sildenafil was well tolerated. Headaches and flushing occurred in both groups. Dyspepsia was reported by two patients in the sildenafil group. In conclusion, oral sildenafil seems to be an effective and safe treatment for ED in selected patients with chronic renal failure on hemodialysis.
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PMID:Efficacy of oral sildenafil in hemodialysis patients with erectile dysfunction. 1239 48

The treatment of erectile dysfunction (ED) has been revolutionised by new agents to inhibit the enzyme PDE5. The scientific basis of this treatment of ED includes relaxation of the corpus cavernosum smooth muscle tissue by inhibition of PDE5 that breaks down cGMP, the key pathway for the production of erectile function in humans. Many clinical studies, both pre- and post-marketing, have demonstrated the clinical efficacy and safety of sildenafil (Viagra, Pfizer) - the first approved selective PDE inhibitor for the treatment of ED. Sildenafil is inhibitory of PDE5 at a rate tenfold higher than for the next PDE (PDE6), which produces visual changes through the retinal rods. Its clinical effectiveness has been well documented in the majority of men with ED irrespective of aetiology. The aetiology of ED, also, does not appear to effect the function of sildenafil in relaxing corpus cavernosum smooth muscle tissue. Adverse events are usually associated with the vascular changes from PDE5 inhibition. These include headache and flushing. Each of these adverse events, however, declines with medication use. With the use of sildenafil, it has been clearly, clinically demonstrated that the selective inhibition of PDE5 is an appropriate, effective, safe method for the treatment of ED of all aetiologies and severities.
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PMID:Long-term use of sildenafil. 1261 92

Treatment with antidepressants, especially agents with potent serotonergic effects, is frequently associated with sexual side effects. In the present study, we examined the efficacy of sildenafil, a potent phosphodiesterase inhibitor, in the treatment of elderly men (n = 10; 70-81 years) with erectile dysfunction induced by antidepressant treatment for major depressive disorder. Eligible subjects were instructed to add sildenafil (25-50 mg/day) to their current drug treatment. Clinical assessment of erectile function was performed at beginning of treatment with sildenafil and at follow up, 4 weeks later. All patients reported an improvement of their erectile capacity, and in 7 out of 10 subjects, erectile function returned to a normal level. Sildenafil appears to be a safe and well-tolerated agent in elderly subjects. We noted side effects in 2 patients (flashes), but the side-effects were bothersome only to one patient (headache). It appears that sildenafil coadministration improves erectile dysfunction associated with selective serotonin reuptake inhibitor ongoing treatment in elderly patients.
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PMID:Sildenafil for selective serotonin reuptake inhibitor-induced erectile dysfunction in elderly male depressed patients. 1450 18

This was a double-blind, placebo-controlled, flexible-dose study of the efficacy and safety of sildenafil in men with erectile dysfunction (ED) and clinically stable coronary artery disease (CAD). Patients were randomized to receive sildenafil or placebo for 12 weeks. Primary outcomes were questions 3 and 4 of the International Index of Erectile Function (IIEF). Secondary outcomes included the other IIEF questions and functional domains, the Life Satisfaction Checklist, the Erectile Dysfunction Inventory of Treatment Satisfaction, 2 global efficacy assessment questions, and intercourse success rate. By week 12, sildenafil-treated patients (n = 70) showed significant improvements on questions 3 and 4 compared with placebo-treated patients (n = 72; p <0.01). Larger percentages of sildenafil-treated patients reported improved erections (64%) and improved intercourse (65%) compared with placebo-treated patients (21% and 19%, respectively). Sildenafil-treated patients were highly satisfied with treatment and their sexual life compared with placebo-treated patients. Forty-seven percent of sildenafil- and 32% of placebo-treated patients experienced adverse events, including transient headache, hypertension, flushing, and dyspepsia. There were no serious drug-related cardiovascular effects. Thus, sildenafil is an effective and well-tolerated treatment for ED in men with CAD. Sildenafil was not associated with additional safety risks in this patient population.
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PMID:Efficacy and safety of sildenafil citrate in men with erectile dysfunction and stable coronary artery disease. 1471 38

Sildenafil, a selective inhibitor of the cyclic guanosine monophosphate (cGMP) degrading phosphodiestrase 5 (PDE5), induced migraine without aura in 10 of 12 migraine patients and in healthy subjects it induced significantly more headache than placebo. The aim of the present study was to determine whether the pain-inducing effects of sildenafil would be reflected in plasma levels of important signalling molecules in migraine: cGMP, cyclic adenosine monophosphate (cAMP) and calcitonin gene-related peptide (CGRP). Ten healthy subjects (four women, six men) and 12 patients (12 women) suffering from migraine without aura were included in two separate double-blind, placebo-controlled, cross-over studies in which placebo or sildenafil 100 mg was administered orally. Plasma levels of CGRP, cAMP and cGMP were determined in blood from the antecubital vein. Despite the ability of sildenafil to induce headache and migraine, no significant differences in plasma levels of CGRP, cGMP and cAMP were detected after sildenafil compared with placebo. In conclusion, plasma levels of CGRP, cGMP and cAMP remain normal during sildenafil-induced headache or migraine. However, since previous studies indicate an important role of these signalling molecules, the present study questions whether cAMP and cGMP in peripheral blood can be used for monitoring pathophysiological events in headache and migraine mechanisms.
Cephalalgia 2004 Jul
PMID:Plasma levels of cAMP, cGMP and CGRP in sildenafil-induced headache. 1519 97

Sildenafil revolutionised the treatment of erectile dysfunction (ED) on its introduction in 1998. Not only is it effective, but is, perhaps even more importantly, an extremely acceptable manner in which to treat ED (i.e., oral pharmacotherapy), compared to the other treatments that were available at that time (e.g., intracavernosal injection). Whilst sildenafil remains the market leader for ED treatment, it does have some shortcomings: its clinical efficacy is diminished in 'difficult to treat' patient groups, such as diabetics, side effects, such as blue-tinged vision and headache, and the need to time the ingestion of sildenafil to 1 h prior to expected time of sexual intercourse. Recently, newer phosphodiesterase inhibitors ('sons of viagra') have become available, and potentially to improve upon, what has become regarded as the gold standard for ED treatment. This review article discusses the differences between vardenafil, tadalafil and sildenafil, in order to allow the clinician to make an informed decision as to which phosphodiesterase inhibitor to prescribe when dealing with the ever expanding number of patients seeking help for ED.
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PMID:New phosphodiesterase inhibitors in the treatment of erectile dysfunction. 1550 Mar 70

Erection is a neurovascular event that involves spinal and supra spinal pathways. The final common pathway involves the release of nitric oxide (NO) from both endothelial cells and neurons, which acts as a vasodilator causing penile engorgement and erection. NO is degraded by the enzyme phosphodiesterase (PDE) type 5 in the penis. Erectile dysfunction (ED), defined as the persistent inability to achieve and/or maintain an erection sufficient for satisfactory sexual performance, results when the neurovascular pathway is interrupted by medical conditions or drugs. A 15-item self-administered questionnaire, the International Index of Erectile Function (IIEF), is one of the most useful tools to evaluate erectile function (EF) in clinical trials, although of much less use in routine clinical practice. The MMAS (Massachusetts Male Aging Study) was the first major epidemiological investigation to study the prevalence of ED. The study found that ED was three times more common in patients with diabetes mellitus. The aetiopathogenesis of ED in diabetes is multifactorial, with vascular and neural factors being equally implicated. Hyperglycaemia is believed to give rise to biochemical perturbations that lead to these microvascular changes. In the MMAS, ED in diabetes was strongly correlated with glycaemic control, duration of disease and diabetic complications. The incidence increased with increasing age, duration of diabetes and deteriorating metabolic control, and was higher in individuals with type 2 diabetes than those with type 1.ED in men with diabetes often affects their quality of life and, as patients are often reluctant to come forward with their symptoms, a carefully taken history is one of the most useful approaches in identifying affected individuals. The PDE inhibitors have revolutionised the management of ED and oral drug therapy is currently first-line therapy for the condition. These agents act by potentiating the action of intracavernosal NO, thereby leading to a more sustained erection. Sildenafil was the first PDE5 inhibitor to undergo evaluation and has been studied extensively. More recently two other agents, vardenafil and tadalafil, have been introduced. All the drugs have been shown to be effective across a wide range of aetiologies of ED, including diabetes. The drugs have been shown to improve EF domain scores, penetration and maintenance of erection, resulting in more successful intercourse. Their effects are greater at higher doses. Sildenafil and vardenafil are shorter-acting agents, while tadalafil has a longer half-life allowing the user more flexibility in sexual activity. Common adverse effects include headache, nasal congestion and dyspepsia, all actions related to inhibition of PDE5. The drugs are generally well tolerated and withdrawal from the clinical studies as a result of drug-related adverse effects were rare. The use of PDE5 inhibitors in the presence of oral nitrates is absolutely contraindicated. The clinical studies to date have not evaluated the use of one drug in the case of treatment failure with another agent. Sublingual apomorphine, which stimulates central neurogenic pathways, is a new agent and may be a suitable alternative in those patients in whom PDE5 inhibitors are ineffective or contraindicated. In clinical trials, all IIEF domains except sexual desire were found to have improved after apomorphine. The median times to erection in these studies were 18.9 and 18.8 minutes for the 2 and 3mg doses, respectively. Intraurethral and intracavernosal alprostadil may be a useful alternative when oral drug therapy is ineffective or contraindicated. The management of ED in the diabetic patient may often involve a multidisciplinary approach where psychosexual counselling and specialist urologist advice is required in addition to the skills and expertise of the diabetologist. Finally, the introduction of the new oral agents have completely revolutionised the management of ED and allowed more individuals to come forward for treatment.
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PMID:New treatment options for erectile dysfunction in patients with diabetes mellitus. 1553 69

Chronic heart failure (CHF) is an increasingly common cardiovascular disorder. Many patients who have CHF report moderate to marked decreases in the frequency of sexual activity, and up to 75% of patients report erectile dysfunction (ED). There are few controlled clinical data on the efficacy and safety of sildenafil citrate in men who have ED and CHF; thus, we evaluated these parameters in patients who had stable CHF. This was a double-blind, placebo-controlled, flexible-dose study. Men who had ED and stable CHF were randomized to receive sildenafil or placebo for 12 weeks. Primary outcomes were questions 3 and 4 of the International Index of Erectile Function. Secondary outcomes included the 5 functional domains of the International Index of Erectile Function, 2 global efficacy assessment questions, intercourse success rate, the Erectile Dysfunction Inventory of Treatment Satisfaction, and the Life Satisfaction Checklist. By week 12, patients who received sildenafil (n = 60) showed significant improvements on questions 3 and 4 compared with patients who received placebo (n = 72; p <0.002). Larger percentages of patients who received sildenafil reported improved erections (74%) and improved intercourse (68%) compared with patients who received placebo (18% and 16%, respectively). Intercourse success rates were 53% among patients who received sildenafil and 20% among those who received placebo. Patients who received sildenafil were highly satisfied with treatment and their sexual life compared with patients who received placebo. Sixty percent of patients who received sildenafil and 48% of patients who received placebo developed adverse events, including transient headache, facial flushing, respiratory tract infection, and asthenia. The incidence of events related to cardiovascular effects was low. Sildenafil is an effective and well-tolerated management of ED in men who have mild to moderate CHF.
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PMID:Efficacy and safety of sildenafil citrate in men with erectile dysfunction and chronic heart failure. 1561 91

Erectile dysfunction (ED) affects up to 50% of men, between 40 and 70 years of age. In the first major trial of sildenafil in ED, at 24 weeks, improved erections were reported by 77 and 84% of men taking sildenafil 50 and 100mg, respectively. Subsequently, sildenafil has been reported to be effective in men with ED associated with diabetes and prostate cancer, and in psychogenic ED. Sildenafil is safe in men with coronary artery disease, provided it is not used with the nitrates (a contraindication). The most commonly reported adverse effects with sildenafil are headache, flushing and dyspepsia. Vardenafil is more potent and more selective than sildenafil at inhibiting phosphodiesterase-5. Vardenafil is similarly effective to sildenafil in the treatment of ED. The only advantage that vardenafil has over sildenafil is that it does not inhibit phosphodiesterase-6 to alter colour perception, a rare side effect which sometimes occurs with sildenafil. Tadalafil has a longer duration of action than sildenafil and vardenafil. Tadalafil is similarly effective as sildenafil in the treatment of ED. In comparison studies, tadalafil is preferred to sildenafil (50/100mg) by men with ED, possibly because of its longer duration of action. Of the phosphodiesterase inhibitors, tadalafil may displace sildenafil as the drug of choice among men with ED.
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PMID:Comparison of clinical trials with sildenafil, vardenafil and tadalafil in erectile dysfunction. 1570 77


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