Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0015672 (fatigue)
 51,768 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 72-year-old man with epiphora secondary to bilateral canalicular stenosis resulting from long-term treatment with 0.125% to 0.25% echothiophate iodide (phospholine iodide) drops for glaucoma underwent bilateral conjunctivodacryocystorhinostomies with Jones' tubes. Within days after undergoing this surgery, he experienced severe unexplained diarrhea, fatigue, weight loss, and prostration. He cancelled his postoperative ophthalmic appointment because of "medical illness." He required admission to his local hospital where extensive studies were done in an attempt to establish the cause of this life-threatening condition. After stopping the echothiophate iodide drops, all symptoms disappeared within two days. Drug toxicity is a previously unreported complication of conjunctivodacryocystorhinostomy, and this case demonstrates that topical medications have enhanced systemic absorption after lacrimal surgery with placement of fistulizing prosthetic devices. One must be aware of this possible complication, not only with long-acting anticholinesterases, but with topical sympathomimetic drugs (especially in cardiac patients) as well as cycloplegic agents in children.
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PMID:Phospholine iodide toxicity and Jones' tubes. 739 39

Sotalol is a beta-blocking drug devoid of membrane stabilizing properties, as well as intrinsic sympathomimetic actions, or cardioselectivity. In addition, sotalol prolongs atrial and ventricular repolarization (Class III antiarrhythmic activity). It appears to have less myocardial depressant effect than other beta-blocking agents. Given orally, bioavailability of the drug reaches 100%. Sotalol's plasma half-life is 15 hours (range 7-18) and is dependent only on renal function. In clinical practice, it has been found effective in the suppression of nearly all supraventricular and ventricular dysrhythmias except those related to prolonged ventricular repolarization. Most common adverse effects are dyspnea, bradycardia, and fatigue, which results in drug termination in 16% of the cases. Torsades de pointes usually associated with bradycardia and drug induced QTc prolongation has been reported in 1.9%-3.5% of the patients receiving sotalol. This complication may be reduced by limiting the dose (< 640 mg/day) especially in patients with impaired renal function. In addition hypokalemia must be avoided. To sum up, the combination of Class II and Class III effects may carry additional benefits. However, further studies are required to test such hypotheses.
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PMID:Sotalol: from "just another beta blocker" to "the prototype of class III antidysrhythmic compound". 777 Mar 66

The effects of beta 2-stimulants [clenbuterol (CB) and terbutaline (TB)] on the contractility of the urethral sphincter of female dogs were studied by measuring intraurethral pressure (IUP) during stimulation of bilateral pudendal nerves. In nine dogs 1, 10 and 100 micrograms/kg. of CB were administered, but no changes in IUP were observed. In the other 33 dogs, sphincteric fatigue was experimentally prepared by electrically stimulating the pudendal nerves at 15 V, 20 Hz for 30 to 40 minutes. In fatigued sphincters, CB (n = 17) and TB (n = 7) increased the contracting pressure (pressure difference between stimulation-generated peak level and baseline level of IUP). The inotropic effect of beta 2-stimulant (TB) on the fatigued urethral sphincter was abolished by a beta-blocker, propranolol. From the present study it was concluded that beta 2-stimulants have little effect on the total contractility of the nonfatigued urethral sphincter because it is composed of smooth and striated muscles (fast- and slow-contracting muscles). However, beta 2-stimulants enhanced the contractility of fatigued urethral sphincter. These results suggest that beta 2-stimulants act on fast-contracting fibers in the urethral sphincter because the inotropic effect of sympathomimetic amine is much greater on fatigued, fast-contracting fibers than on nonfatigued ones and its depressive effect on slow-contracting fibers is not potentiated after fatigue.
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PMID:Effects of beta 2-stimulants on contractility and fatigue of canine urethral sphincter. 812 95

Nebivolol is a new selective beta 1-adrenergic blocking agent, that possesses a peculiar pharmacodynamic profile and an original chemical structure, by which it differs from traditional beta 1-blockers. Nebivolol is a racemic mixture of two enantiomers in equal ratios. It is endowed with a highly selective beta 1-blocking activity, and does not show an intrinsic sympathomimetic activity. Nebivolol is endowed with peripheral vasodilating properties mediated by the modulation of the endogenous production of nitric oxide. It does not significantly decrease airway conductance compared with atenolol and propranolol. Nebivolol does not compromise the left ventricular function, but it may increase stroke volume, and does not reduce heart inotropism during exertion. Nebivolol is quite safe and is well tolerated, also when compared to traditional beta-blockers. The most common adverse effects are dizziness, headache and fatigue. Owing to its combined dual mechanism of action, nebivolol leads to a unique haemodynamic and therapeutic profile by which it may be advantageous in essential hypertension, ischaemic heart disease and congestive heart failure.
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PMID:Pharmacology of nebivolol. 999 Jun 50

To compare the efficacy and side effects of beta-blockers with intrinsic sympathomimetic activity (ISA) to those without ISA, we retrospectively reviewed patients diagnosed with neurocardiogenic syncope (NCS) as determined by head-up tilt table testing. Four hundred and thirty-one patients (mean age of 57 +/- 25 years) underwent head-up tilt table testing for syncope of unknown etiology, of which 120 patients were diagnosed with NCS; 87 of these patients were treated with beta-blocker therapy. Only 56 patients could be contacted during follow-up. Twenty-eight patients were treated with beta-blockers with ISA (acebutolol or pindolol) and 28 received beta-blockers without ISA (atenolol or metoprolol) based on physician preference and followed for up to 2 years. During the follow-up period, beta-blockers with or without ISA had comparable clinical efficacy in suppressing recurrent syncope in patients with NCS. However, beta-blockers with ISA were better tolerated and caused less fatigue (32% side effects) as compared to those without ISA (50% side effects; p = 0.23). The benefits of beta-blockers with ISA were more pronounced in patients less than 60 years old (19% side effects with beta-blocker with ISA as compared to 85% side effects with beta-blocker without ISA; p = 0.0004). Beta-blockers without ISA appear to be better tolerated and caused less fatigue in patients 65 years old or greater (20%) than in patients less than 65 years old (85%; p = 0.0002).
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PMID:The effects of intrinsic sympathomimetic activity on beta-blocker efficacy for treatment of neurocardiogenic syncope. 1074 73

Attention Deficit Hyperactivity Disorder (ADHD) is a relatively frequent affection that can generate severe problems (school, social, professional) if no take in charge is done. Treatment of ADHD is generally multifactorial; it can associate medical treatment, comportemental and analytical psychotherapies, reeducation of associated disorders (orthophony, psychomotor reeducation) and educative approach. Methylphenidate, considered as therapeutic reference, is a central nervous system stimulant. It produces a stimulation of vigilance and superior mental activities, a diminution of fatigue sensation and sleep need, an anorexigen power and sympathomimetic effect. Its mechanism of action is abundantly studied and is not completely known. Principal hypothesis are: increase of chemical mediators biodisponsibility and change in cerebral blood flow delivery. In France, it is agreed since 1995 for treatment of ADHD in over 6 years-old child. Ritaline 10 mg is registered on the narcotic list and an initial hospital prescription is needed, reserved to specialists and/or to neurologic, psychiatric and pediatric services. Mid-1995, 2.8% (namely 1.5 millions) of 5 to 18 years-old american children have taken this drug. Methylphenidate is effective on each three principal symptoms of ADHD: it decreases the level of activity, it improves apprentice capacity, just as school performances and it eases social interactions. The therapeutic schedule at short and middle term is reassuring, with substantial profits on school, familiar and social plans, but unknowns subsist and opinions diverge about long term efficacity. Methylphenidate is not the only one used in ADHD treatment. Other products, like dextroamphetamine and pemoline have been used in the USA and are for those who can't tolerate methylphenidate or badly respond to it. Those other drugs are not commercialized in France. The limits of stimulating drugs (fear to favour toxicomania, undesirable effects that need to stop treatment or non-responsive hyperactive children), just as positives experiences with antidepressants (especially on enuresis) led to use tricyclic antidepressants as second-line agents in ADHD treatment. Their efficiency is less and their well known side-effects are sometimes constraining. Antidepressants that inhibit serotonin recapture, MAOI and bupropion, central antihypertensive, such as clonidine and guanfacine have been tried in ADHD treatment as third-line agents. They should be useful on non-responsive or patients who can't tolerate stimulants or tricyclic antidepressants. Analytical and comportemental psychotherapies are used in addition to medicamental treatment. Reeducation of troubles such as dyslexia, language delay, corporal scheme troubles or fine coordination trouble is obtained by orthophony and psychomotricity. It's very important to instaurate an educative strategy in order to contend inattention and hyperactivity. Regular conservations with parents and child are necessary. The whole american literature shows better efficiency of multimodal treatment of ADHD in child, as opposed to single stimulant treatment.
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PMID:[Prescribing ritalin in combined modality management of hyperactivity with attention deficit]. 1176 Jun 93

Nebivolol is a lipophilic beta 1-blocker. It is devoid of intrinsic sympathomimetic or membrane stabilising activity but appears to have nitric oxide-mediated vasodilatory effects. Nebivolol 5 mg once daily is well tolerated in patients with hypertension. Adverse events are infrequent, transient and mild to moderate. Those reported most often include headache, fatigue, paraesthesias and dizziness. Several studies reported no signs of orthostatic hypotension with Nebivolol.
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PMID:[Nebivolol treatment in essential arterial hypertension]. 1209 33

In response to questions about the safety of ephedra-based dietary products, ephedra-free products are now available. Many contain synephrine, a sympathomimetic amine with structural similarities to ephedra. We present a 22-year-old, previously healthy, African American male with sickle cell trait who developed rhabdomyolysis after ingestion of a synephrine-containing dietary supplement. The patient developed fatigue, dehydration, and myalgias while exercising. He developed severe rhabdomyolysis, with a peak creatine phosphokinase level of 2.8 million U/L, complicated by pulmonary edema, acute renal failure, disseminated intravascular coagulation, and bilateral compartment syndromes in his lower extremities. He required prolonged hospitalization for hemodialysis, multiple wound debridements, hyperbaric oxygen therapy, and physical therapy. He has permanent sensory and motor neurological deficits in his distal lower extremities. Military physicians should routinely inquire about the use of dietary supplements, educate patients about the potential adverse reactions associated with these agents, and encourage healthy diets and exercise for weight loss.
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PMID:A case of severe exercise-induced rhabdomyolysis associated with a weight-loss dietary supplement. 1761 52

There is an evidence that increased capillary permeability in the standing position is related to a deficit in the sympathetic nervous system. The leakage of this fluid leads to various clinical conditions which frequently puzzle the consulting physician because despite the frequency of this condition intelligent physicians and patients are unaware of the cause of their condition. One of the most common manifestations is the inability to lose weight despite proper dieting. A randomized study comparing the efficacy of a diuretic, a converting enzyme inhibitor, spironolactone and a sympathomimetic amine on weight loss in diet refractory women found that only the latter in the form of dextroamphetamine sulfate demonstrated significant weight reduction over a six month time span. In fact, the dextroamphetamine sulfate proved effective when given in the next 6 months to the three groups failing to respond for the first 6 months. The diagnosis of a deficit in sympathomimetic amines is established by demonstrating an abnormal clearance of a water load in the erect position and exclusion of other conditions that are associated with an abnormal free water clearance, e.g., hypothyroidism, renal or liver disease or congestive heart failure. The original definition of an abnormal water load test was excretion of <55% of a 1500 ml water load in 6h but we found that <75% defines a greater population who suffer from this problem. There are several conditions that have proven refractory to conventional theory that respond quickly and effectively to sympathomimetic amines. There have been many anecdotal reports of relieving interactable pain syndromes quickly and efficiently with sympathomimetic amine theory, despite failure with a multitude of other therapies. These include interstitial cystitis and pelvic pain that was attributed to endometriosis, gastrointestinal pain including esophagitis and gastroparesis, headaches, joint pain, fibromyalgia, and carpal tunnel syndrome. It is not clear if the improvement in pain is related to a decrease in fluid retention or a direct effect of the sympathomimetic amines on the sympathetic nervous system. Sympathomimetic amine theory has helped other conditions besides pain, e.g., chronic fatigue, vasomotor symptoms in young women not associated with decreased ovarian egg reserve, and chronic urticaria resistant to all other therapies. Thus, these studies strongly suggest that physicians be aware of this condition involving a deficit in the sympathetic nervous system when faced with various enigmatic complaints especially if standard therapy has not proven effective.
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PMID:A disorder of sympathomimetic amines leading to increased vascular permeability may be the etiologic factor in various treatment refractory health problems in women. 1776 3

Beta-blockers (beta-blockers) have demonstrated their value across the cardiovascular disease spectrum. Beta-blockers effectively lower blood pressure in patients with hypertension and provide symptomatic or mortality benefits in patients with heart failure and in post-myocardial infarction patients. However, despite their utility, beta-blockers remain underused. There have been recent concerns that beta-blockers as a class are not as effective as once thought in uncomplicated hypertension due to a relatively weak effect on reduction of stroke and the absence of an effect on coronary heart disease when compared with placebo or no treatment. Underuse can, in part, be related to tolerability concerns. Beta-blockers have been traditionally associated with side effects including depression, fatigue, sexual dysfunction, and cold extremities, which limit their acceptance by patients and physicians and may lead to discontinuation of therapy. Because of inherent heterogeneity of the beta-blocker class in terms of adrenergic receptor selectivity, intrinsic sympathomimetic activity, and vasodilatory activity, these agents vary in tolerability profile. Recently, more attention has been focused on the third-generation vasodilatory beta-blockers (ie, carvedilol, labetalol, and nebivolol), with the recognition that these agents may diverge in meaningful ways from the traditional beta-blockers. By examining the differences among members of the beta-blocker class, it may be possible to determine whether and which tolerability issues are indeed a class effect of beta-blockers or whether these agents should be evaluated on a case-by-case basis.
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PMID:Are tolerability concerns a class effect of beta-blockers in treating patients with hypertension? 1917 10


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