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Query: UMLS:C0012833 (dizziness)
 9,689 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Eighty-two patients were evaluated for erectile failure with a comprehensive history, physical examination, hormonal testing, noninvasive Doppler examination (PBI), and nocturnal penile tumescence (NPT). After these studies all patients received intracavernous injection with a combination of papaverine (50 mg) and phentolamine (1.66 mg), and both tumescence and rigidity were monitored. Rigidity response was compared with the PBI. The number of patients with a poor rigidity response in each PBI category were: 3 of 5 with a PBI of less than 0.6 (vasculogenic), 7 of 11 with a PBI of 0.6-0.75 (ambiguous), and 25 of 66 with a PBI of 0.75-1.0 (normal). These results indicate only a marginally significant association between PBI and intracavernous injection. The procedure was safe with no long-term sequelae from injection observed, and no surgical intervention was required. Complications of injections included reversible priapism in 11 patients (13.4%), transient dizziness in 10 patients (12.2%), and hematoma in 5 patients (6.2%). This study suggests that intracavernous injection with a drug combination may be a more sensitive screening test for vasculogenic impotence than noninvasive Doppler studies because it more closely simulates the erectile response.
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PMID:Intracavernous injections of papaverine and phentolamine: correlation with penile brachial index. 277 61

Postmarketing adverse drug reaction reports for amoxapine, maprotiline hydrochloride, and trazodone hydrochloride and premarketing adverse drug reaction data for bupropion hydrochloride and nomifensine maleate are reviewed, and the role of the new agents in the management of depressive illness is discussed. Nomifensine was withdrawn from markets worldwide because of reports of serious hypersensitivity reactions, especially hemolytic anemia, and marketing of bupropion in the United States was delayed after seizures occurred in bulimic patients in clinical trials. Amoxapine and maprotiline, when taken in overdose attempts, are more toxic and cause more serious central nervous system reactions than the standard tricyclics. Acute renal failure and an increased mortality rate are associated with amoxapine overdose. Amoxapine causes several acute and chronic untoward neurologic and endocrine reactions not commonly associated with the standard tricyclics. For maprotiline and bupropion, maximum doses have been established because of dose-related seizures. Trazodone has minimal effect on cardiac conduction; its main cardiovascular effects are hypotension, orthostasis, and dizziness. The trazodone package insert has been revised to warn of priapism; patients with prolonged or inappropriate penile erections are instructed to discontinue the drug and notify the physician. Serious cardiovascular and neurologic toxicities are rare with trazodone overdose. Of the newly marketed antidepressants, only trazodone offers some advantages over the tricyclic and tetracyclic agents in the areas of side effects and toxicities. The number and type of patients exposed to a new drug during clinical trials is too small for detection of rare but potentially serious adverse effects.
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PMID:Adverse reactions to five new antidepressants. 308 84

Trazodone's unique chemical structure reflects its distinct pharmacologic profile. Its antidepressant efficacy is postulated to occur through serotonin reuptake inhibition. It has little effect on other neurotransmitter systems. In the United States it has been studied in several double-blind trials which compared it to standard antidepressants and placebo. Both in- and outpatients spanning a spectrum of age and diagnoses have been studied. Trazodone has been shown to be at least as effective as standard antidepressants. There are few anticholinergic or cardiovascular side effects. Adverse reactions include drowsiness, dizziness, headache, nausea and rarely, priapism. It is relatively safe in overdose. Trazodone deserves special consideration in the treatment of patients with depression accompanied by marked agitation, anxiety, and insomnia, as well as those unable to tolerate anticholinergic side effects.
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PMID:Overview of USA controlled trials of trazodone in clinical depression. 313 15

Intracavernous papaverine injection is often used in the diagnosis and treatment of male impotence. Prolonged erection and/or priapism are well known local complications. Systemic side-effects characterized by discomfort and dizziness due to rapid escape of the drug into the vascular circulation also can occur in patients with venous leakage. Thus, venous leakage should be ruled out prior to intracavernous injection of papaverine in the treatment of impotence. Ligation of the deep dorsal vein and the small veins around the tunica albuginea will lessen the problem.
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PMID:Systemic complication of intracavernous papaverine injection in patients with venous leakage. 334 Oct 94

Earlier nonselective alpha 1-adrenergic blocking drugs such as phentolamine and phenoxybenzamine are now restricted to the pharmacological management of alpha 1-adrenergic crisis and phaeochromocytoma. Prazosin, the first selective alpha 1-blocker approved for the treatment of hypertension, became available in the mid-1970s. Additional alpha 1-blockers such as doxazosin and terazosin have been introduced during recent years. The undesirable effects of all members of this class are similar. Most adverse events can be attributed to reversible competitive antagonism of postsynaptic alpha 1-adrenergic receptors in tissues that sustain high levels of alpha-adrenergic sympathetic tone, e.g. resistance arteries, capacitance veins and the urinary bladder outflow tract. Orthostatic hypotension with a sensation of intense faintness and occasional syncope, can occur shortly after the initial dose. Aggravating factors include upright posture, intravascular volume depletion and concurrent administration of other medications that lower blood pressure, including all other classes of antihypertensive drugs. The problem is reduced or avoided by the choice of low starting doses, beginning treatment at bedtime and by minimising other risks. Among overall adverse effects, asthenia, dizziness, faintness and syncope predominate and occur in 10 to 20% of patients, leading to discontinuation of therapy in about half that number. Infrequent adverse events include headache, drowsiness, palpitations, urinary incontinence and priapism. Some patients experience a 1 to 2kg bodyweight gain which may be associated with secondary hyperaldosteronism. Tolerance appears to develop to the benefits of alpha 1-blockade in patients with congestive heart failure, but not in hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Adverse effects of alpha 1-adrenergic blocking drugs. 791 78

Nefazodone hydrochloride is a phenylpiperazine antidepressant with a mechanism of action that is distinct from those of other currently available drugs. It potently and selectively blocks postsynaptic serotonin (5-hydroxytryptamine; 5-HT) 5-HT2A receptors and moderately inhibits serotonin and noradrenaline (norepinephrine) reuptake. In short term clinical trials of 6 or 8 weeks' duration, nefazodone produced clinical improvements that were significantly greater than those with placebo and similar to those achieved with imipramine, and the selective serotonin reuptake inhibitors (SSRIs) fluoxetine, paroxetine and sertraline. The optimum therapeutic dosage of nefazodone appears to be between 300 and 600 mg/day. Limited long term data suggest that nefazodone is effective in preventing relapse of depression in patients treated for up to 1 year. Analyses of pooled clinical trial results indicate that nefazodone and imipramine produces similar and significant improvements on anxiety- and agitation-related rating scales compared with placebo in patients with major depression. Short term tolerability data indicate that nefazodone has a lower incidence of adverse anticholinergic, antihistaminergic and adrenergic effects than imipramine. Compared with SSRIs, nefazodone causes fewer activating symptoms, adverse gastrointestinal effects (nausea, diarrhoea, anorexia) and adverse effects on sexual function, but is associated with more dizziness, dry mouth, constipation, visual disturbances and confusion. Available data also suggest that nefazodone is not associated with abnormal weight gain, seizures, priapism or significant sleep disruption, and appears to be relatively safe in overdosage. Nefazodone inhibits the cytochrome P450 3A4 isoenzyme and thus has the potential to interact with a number of drugs. Further long term and comparative studies will provide a more accurate assessment of the relative place of nefazodone in the management of major depression. Nonetheless, available data suggest that nefazodone is a worthwhile treatment alternative to tricyclic antidepressants and SSRIs in patients with major depression.
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PMID:Nefazodone. A review of its pharmacology and clinical efficacy in the management of major depression. 921 Oct 88

Sildenafil citrate, an oral therapy for erectile dysfunction, is a selective inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE5), the predominant isozyme metabolizing cGMP in the corpus cavernosum. Chemically, it is a compound of the pyrazolo-pyrimidinyl-methylpiperazine class. Sildenafil has no direct relaxant effect on human corpus cavernosum but enhances the relaxant effect of nitric oxide (NO) on the corpus cavernosum by inhibiting PDE5, which is responsible for degradation of cGMP in this tissue. When sexual stimulation causes local release of NO, inhibition of PDE5 by sildenafil increases concentrations of cGMP in the corpus cavernosum, causing smooth muscle relaxation and blood flow into the penis, resulting in an erection. Sildenafil at recommended doses has no effect in the absence of sexual stimulation. The drug is rapidly absorbed after oral administration, with absolute bioavailability of 40%. Its pharmacokinetics are dose proportional over the recommended dosage range. Maximum plasma concentrations are reached within 30 to 120 minutes after oral dosing in the fasting state. Sildenafil is cleared predominantly by the hepatic microsomal isoenzymes CYP3A4 (major route) and CYP2C9 (minor route). Clinical studies assessed the effect of sildenafil on the ability of men with erectile dysfunction to engage in sexual activity and, specifically, to achieve and maintain an erection sufficient for satisfactory sexual intercourse. Sildenafil was evaluated at doses of 25, 50, and 100 mg in randomized, double-masked, placebo-controlled clinical trials of up to 6 months' duration. The drug was administered to hundreds of patients aged 19 to 87 years having erectile dysfunction of various etiologies for a mean duration of 5 years. Sildenafil was associated with statistically significant improvement in erectile function compared with placebo. Adverse effects reported at a rate of >2% were headache, flushing, dyspepsia, nasal congestion, urinary tract infection, abnormal vision, diarrhea, dizziness, and rash. No cases of priapism were reported. The use of sildenafil is contraindicated in men who are taking organic nitrates, because of the potential for a precipitous decrease in blood pressure. Postmarketing reports and surveillance have revealed at least 39 deaths with sildenafil use in men having a history of heart disease, men taking nitrate medications, and men in poor physical health due to lack of exercise. Many of the men who experienced serious adverse effects or death had a variety of concomitant diseases and were taking multiple medications.
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PMID:Safety and efficacy of sildenafil citrate in the treatment of male erectile dysfunction. 991 1

Sildenafil, a selective inhibitor of phosphodiesterase type 5 (PDE5), is the first in a new class of orally effective treatments for erectile dysfunction. During sexual stimulation, the cavernous nerves release nitric oxide (NO), which induces cyclic guanosine monophosphate (cGMP) formation and smooth muscle relaxation in the corpus cavernosum. Sildenafil facilitates the erectile process during sexual stimulation by inhibiting PDE5 and thus blocking the breakdown of cGMP. Sildenafil alone can cause mean peak reductions in systolic/diastolic blood pressure of 10/7 mm Hg that are not dose related, whereas the heart rate is unchanged. Sildenafil and nitrates both increase cGMP levels in the systemic circulation but at different points along the NO-cGMP pathway. The combination is contraindicated because they synergistically potentiate vasodilation and may cause excessive reductions in blood pressure. Erectile dysfunction is a significant medical condition that shares numerous risk factors with ischemic heart disease, and hence a substantial overlap exists between these patient groups. From extensive clinical trials, the most commonly reported cardiovascular adverse events in patients treated with sildenafil were headache (16%), flushing (10%), and dizziness (2%). The incidences of hypotension, orthostatic hypotension, and syncope and the rate of discontinuation of treatment due to adverse events were <2% and were the same in patients taking sildenafil and those taking placebo. Retrospective analysis of the concomitant use of antihypertensive medications (beta blockers, alpha blockers, diuretics, angiotensin-converting enzyme inhibitors, and calcium antagonists) in patients taking sildenafil did not indicate an increase in the reports of adverse events or significant episodes of hypotension compared with patients treated with sildenafil alone. In clinical trials, the incidence of serious cardiovascular adverse events, including stroke and myocardial infarction, was the same for patients treated with sildenafil or placebo. Concurrent disease states, such as renal or hepatic impairment, or concomitant use of inhibitors of the cytochrome P450 isozyme CYP3A4 could increase systemic exposure to sildenafil. Since the US market launch in April 1998, monitoring of spontaneous adverse event reports in association with sildenafil has demonstrated a pattern that is generally consistent with the experience observed during clinical development, with the exception of infrequent reports of priapism. In conclusion, extensive clinical testing has shown that overall treatment with sildenafil for up to 1 year is well tolerated and is associated with a low incidence of adverse events that result in discontinuation of treatment in <3% of patients.
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PMID:Overall cardiovascular profile of sildenafil citrate. 1007 41

Safety and tolerability of sildenafil citrate was assessed in a population subset of 60 Singaporean men with erectile dysfunction taken from the Asian Sildenafil Efficacy and Safety Study (ASSESS-I), a double-blind, placebo-controlled, flexible-dose study. The men, from two centres, with > or = 6 months' history of erectile dysfunction, were randomized to two treatment arms for 12 weeks. One group (30 patients) received sildenafil (initial dose 50 mg taken 1 h before sexual activity for the first 2 weeks, increased to 100 mg or decreased to 25 mg, according to efficacy and/or tolerability). The remaining 30 patients received a matching placebo. Incidence and type of adverse effects were evaluated at 2, 4, 8 and 12 weeks. Nine patients (30.0%) on sildenafil (33.1% in the full ASSESS-I study) and one patient (3.3%) on placebo (22.8% in the full ASSESS-I study) experienced treatment-related adverse events, the most frequent being headache in the sildenafil group (reported by five patients [16.7%]; 11.0% in the full ASSESS-I study). Flushing, visual disturbance, dizziness, insomnia, myalgia and back pain each occurred in one patient in the sildenafil group (3.3%); in the placebo group, one patient (3.3%) had headache. Importantly, the incidence of cardiovascular and respiratory system adverse events were relatively less than in the full ASSESS-I population (cardiovascular 3.3% in the present study versus 10.2% in the full ASSESS-I population; respiratory 3.3% versus 5.5%). All adverse events were transient and mild, and did not lead to treatment withdrawal. There was no effect on sitting blood pressure, heart rate or standard laboratory parameters; more importantly, there was no incidence of myocardial infarction, stroke or priapism. These results should reassure Singaporean patients and their physicians of the safety of sildenafil for erectile dysfunction.
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PMID:Clinical safety profile of sildenafil in Singaporean men with erectile dysfunction: pre-marketing experience (ASSESS-I evaluation). 1202 21

Quetiapine hemifumarate (QF) is widely used in psychiatry and is associated with regularly occurring side effects such as dizziness and metabolic problems. Apart from these typical adverse events the agent has attracted attention for several rare phenomena (priapism, cholestasis, rhabdomyolysis) that indeed feature anecdotal character, but are nevertheless indispensable for a comprehensive understanding of the factual risk profile of quetiapine. We present the first report of aseptic gingivitis associated with QF in a patient with mental retardation.
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PMID:Aseptic gingivitis related to quetiapine hemifumarate. 2291 85


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