Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0000737 (abdominal pain)
 31,184 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The irritable bowel syndrome (IBS) is a consortium of symptoms including abdominal pain and alterations in the pattern of defaecation. There is no single pathophysiological marker of IBS although it is generally accepted that some patients do have abnormalities of intestinal motility and/or enhanced visceral sensitivity. There is also an increasing acceptance that the central nervous system, an important component of the brain-gut axis, also plays an important role in symptom production both in the response to stress and when there is an underlying affective disorder. During the past decade new therapeutic targets have been identified that have permitted the development of new drugs with therapeutic potential for IBS. Identification and characterization of 5-hydroxytryptamine (5-HT) receptors in the gastrointestinal tract particularly 5-HT3 and 5-HT4 receptors, which are involved not only in modulating gut motility but in visceral sensory pathways, has led to a number of studies of 5-HT3 (Alosetron, Granisetron and Ondansetron) and 5-HT4 (SB-207266A) antagonists. Both classes of drug appear to reduce visceral sensitivity and have inhibitory effects on motor activity in the distal intestine. Early clinical studies suggest that these agents may have a role in painful, diarrhoea-predominant IBS. 5-HT4 agonists (HTF919, Zelmac) may improve constipation-predominant IBS by normalizing bowel habit and thereby reducing abdominal pain. Alternative approaches to reducing visceral sensation include the use of the opioid kappa agonists, which have no central opioid effects although clinical trials have suggested that these agents are not highly effective in relieving IBS pain. There are in addition, new approaches to modify intestinal motility including the development of gut selective muscarinic M3 receptor antagonists such as zamifenacin and the 5-HT4 partial agonist, HTF919. Preliminary studies suggest that these agents may have therapeutic potential in IBS. Anti-depressants are increasingly used to treat affective disorder in IBS but in addition appear to have added value because of their ability to reduce visceral hypersensitivity and alter gut transit. Therapeutic effects are often obtained at doses below those normally used to treat depression. IBS continues to be a therapeutic challenge because of its diverse symptomatology and lack of a single pathophysiological target for drug intervention.
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PMID:Irritable bowel syndrome: new pharmaceutical approaches to treatment. 1058 Sep 22

Tegaserod (Zelmac), an aminoguanidine indole derivative of serotonin, is a selective partial agonist highly selective for 5-HT(4) receptor with an affinity constant in the nanomolar range. Tegaserod does not cause adverse pharmacodynamic effects, is absorbed rapidly after oral administration and distributes widely into tissues. Pharmacokinetics of oral tegaserod are linear in the 2--12 mg dose range. After oral administration tegaserod is metabolized mainly pre-systemically; when absorbed, intact tegaserod is excreted as N-glucuronides mainly via the bile. No clinically relevant drug--drug interactions were identified. Tegaserod has proven safe in toxicity studies. In pharmacodynamic studies, tegaserod stimulated the peristaltic reflex in vitro, increased canine intestinal and colonic motility and transit, reduced visceral afferent firing or sensation in response to distension in animals, and accelerated gastric, small bowel and colonic transit in healthy patients, and small bowel transit in patients with constipation-predominant irritable bowel syndrome. Three large phase III randomized, double-blinded, and placebo-controlled trials were performed predominantly in females (approximately 85%) with constipation-predominant irritable bowel syndrome. Overall, phase III results support efficacy as assessed by the subject's global assessment of relief with significant improvement in secondary endpoints such as abdominal pain, bowel frequency and consistency. Tegaserod was well-tolerated; the most frequent adverse event was transient diarrhoea.
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PMID:Review article: tegaserod. 1120 4

Tegaserod is a medication that has been shown to be of benefit in women with irritable bowel syndrome (IBS) associated with abdominal pain, bloating, and constipation. Tegaserod is a selective serotonin receptor subtype 4 partial agonist designed to interact with the network of cells and nerves throughout the gastrointestinal tract that use serotonin. Tegaserod has been shown to modulate both gastrointestinal motility and visceral sensitivity. Specifically, it increases the peristaltic reflex and decreases visceral sensitivity. Clinical studies have shown that tegaserod improves symptoms of abdominal pain, bloating, and constipation in women with IBS. This article discusses the role of serotonin in gastrointestinal tract physiology, the structure and pharmacokinetic profile of tegaserod, and clinical applications of this new drug.
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PMID:Tegaserod: a new 5-HT4 agonist. 1174 42

Irritable bowel syndrome (IBS) is a common functional bowel disorder of unknown aetiology. It is defined by the presence of gastrointestinal (GI) symptoms including abdominal pain/discomfort, bloating and bowel motor dysfunction. No available therapy is yet effective against all the symptoms of the disorder. Current treatments therefore target individual symptoms but may be accompanied by unpleasant side-effects. Tegaserod is a novel selective serotonin receptor type-4 (5-HT4) partial agonist with structural similarity to 5-HT Tegaserod stimulates small bowel and colonic motility and helps to normalise GI function. Clinical trials using a patient's assessment of efficacy demonstrate that tegaserod significantly improves key symptoms of IBS: abdominal pain/discomfort, bloating and constipation. Tegaserod is well tolerated with an excellent safety profile and represents a significant treatment advance in this difficult-to-treat disorder.
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PMID:Tegaserod: a novel, selective 5-HT4 receptor partial agonist for irritable bowel syndrome. 1183 35

Tegaserod is a selective partial agonist acting on serotonergic type 4 receptors (5-HT(4)). Pharmacodynamic studies indicate that tegaserod is able to stimulate gut propulsion and secretion with a net prokinetic effect. In contrast to other 5-HT(4) agonists endowed with a complex pharmacological profile, tegaserod has a reliable prokinetic activity in the colon. Clinical trials show that tegaserod is effective and safe in the treatment of patients with irritable bowel syndrome. In particular, tegaserod relieves symptoms of abdominal pain, discomfort, abdominal bloating and constipation.
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PMID:Tegaserod: a new 5-HT(4) agonist in the treatment of irritable bowel syndrome. 1215 Jun 98

Anticholinergics and prokinetics are mainstays of therapy for Irritable Bowel Syndrome (IBS) patients despite their limited efficacy and troublesome side-effect profile. The clinical limitations of these drugs are a result of their relative broad and nonspecific pharmacologic interaction with various receptors. Recent advances in gut physiology have led to the identification of various receptor targets that may play a pivotal role in the pathogenesis of IBS. Medicinal chemists searching for safe and effective IBS therapies are now developing compounds targeting many of these specific receptors. The latest generation of anticholinergics, such as zamifenacin, darifenacin, and YM-905, provide selective antagonism of the muscarinic type-3 receptor. Tegaserod, a selective 5-HT4 partial agonist, tested in multiple clinical trials, is effective in reducing the symptoms of abdominal pain, bloating, and constipation. Ezlopitant and nepadudant, selective antagonists for neurokinin receptors type 1 and type 2, respectively, show promise in reducing gut motility and pain. Loperamide, a mu (mu) opioid receptor agonist, is safe and effective for IBS patients with diarrhea (IBS-D) as the predominant bowel syndrome. Fedotozine, a kappa (kappa) opioid receptor agonist, has been tried as a visccral analgesic in various clinical trials with conflicting results. Alosetron, a 5-HT3 receptor antagonist, has demonstrated efficacy in IBS-D patients but incidents of ischemic colitis seen in post-marketing follow-up resulted its removal from the market. Compounds that target cholecystokinin. A, N-methyl-D-aspartate, alpha 2-adrenergic, and corticotropin-releasing factor receptors are also examined in this review.
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PMID:Irritable bowel syndrome neuropharmacology. A review of approved and investigational compounds. 1218 41

Tegaserod, a selective serotonin (5-hydroxytryptamine; 5-HT) 5-HT(4) receptor partial agonist, is indicated in patients with irritable bowel syndrome (IBS) who identify abdominal pain or discomfort and constipation as their predominant symptoms. Tegaserod at dosages of 1 to 12 mg/day exerts pharmacodynamic actions in the upper and the lower gastrointestinal tract, accelerating small bowel and colonic transit in patients with IBS. Tegaserod is rapidly absorbed following oral administration; peak plasma concentrations (C(max)) are reached after approximately 1 hour. Absolute bioavailability is about 10% under fasted conditions. Food reduces the bioavailability of tegaserod by 40 to 65% and the C(max) by 20 to 40%. Systemic exposure to tegaserod is not significantly altered at neutral gastric pH compared with the fasted state (pH 2). Tegaserod is approximately 98% bound to plasma proteins, primarily to alpha(1)-acid glycoprotein, and has a volume of distribution at steady-state of 368 +/- 223L. Tegaserod is metabolised mainly via two pathways. The first is a presystemic acid-catalysed hydrolysis in the stomach followed by oxidation and conjugation which produces the main metabolite of tegaserod, 5-methoxyindole-3-carboxylic acid glucuronide (M 29.0). This metabolite has negligible affinity for 5-HT(4) receptors and is devoid of promotile activity. The second is direct glucuronidation which leads to generation of three isomeric N-glucuronides. The plasma clearance of tegaserod is 77 +/- 15 L/h, with an estimated terminal half-life of 11 +/- 5 hours following intravenous administration. Approximately two-thirds of the orally administered dose of tegaserod is excreted unchanged in faeces, with the remainder excreted in urine, primarily as M 29.0. The pharmacokinetics of tegaserod are dose-proportional over the range 2 to 12mg given twice daily for 5 days, with no relevant accumulation. The pharmacokinetics of tegaserod in patients with IBS are comparable to those in healthy individuals, and similar between men and women. No dosage adjustment is required in elderly patients or those with mild to moderate hepatic or renal impairment. Tegaserod should not be used in patients with severe hepatic or renal impairment. No clinically relevant drug-drug interactions with tegaserod have been identified. In vivo drug-drug interaction studies with theophylline [a cytochrome P450 (CYP) 1A2 prototype substrate], dextromethorphan (a CYP2D6 prototype substrate), digoxin, warfarin and oral contraceptives have indicated no clinically relevant interactions and no requirement for dosage adjustment.
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PMID:Clinical pharmacokinetics of tegaserod, a serotonin 5-HT(4) receptor partial agonist with promotile activity. 1240 41

The management of the irritable bowel syndrome (IBS) remains unsatisfactory. For abdominal pain, antispasmodics are, at best, of only modest efficacy. Tricyclic antidepressants in low dose are useful (with the number needed to treat being three), but side effects and patient concerns regarding use of a centrally acting agent for depression remain limitations. Selective serotonin reuptake inhibitors are of uncertain efficacy in IBS. Opioid agonists, especially loperamide, are useful for diarrhea but not for pain in IBS; rebound constipation also remains a problem. Bile salt sequestering agents are not of established value in IBS but seem to be useful clinically in a small group of IBS patients with diarrhea. Aloestron, a 5HT(3) antagonist, should be reserved, if available, for women with severe diarrhea predominant IBS who have failed to respond to conventional therapy, and started at a low dose. Fiber and bulking agents may help constipation in some trials, but the evidence that they are efficacious in IBS is equivocal; they are frequently prescribed as first-line drugs for IBS regardless of the primary bowel disturbance but often increase bloating, gas, and pain. Laxatives are not of established value in IBS but are often taken by patients with constipation predominant IBS. Tegaserod, a partial 5HT(4) agonist, is now available in the United States and other countries for use in women with IBS whose primary bowel symptom is constipation; its efficacy in men and in those with alternating bowel habits is unknown. Probiotics are of uncertain efficacy. Chinese herbal medicine data are insufficient. Other new drugs in development include the cholecystokinin antagonists and novel visceral analgesics. Both current and potential therapies for IBS are reviewed in this article.
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PMID:Pharmacologic therapy for the irritable bowel syndrome. 1273 51

The irritable bowel syndrome (IBS) remains a therapeutic challenge in part because of the limited understanding of the pathophysiology. The placebo response rate varies in randomized controlled trials from 20 to 70%, and can persist for up to at least 1 year. It is contentious whether dietary fibre and bulking agents relieve the symptoms of IBS; constipation probably improves. Anticholinergic and antispasmodic agents are of questionable benefit in IBS despite positive meta-analyses of poor quality trials. A meta-analysis concluded that the tricyclic antidepressants were superior to placebo in IBS, although the individual trial results were variable. Selective serotonin reuptake inhibitors are of uncertain benefit. Laxatives are used for constipation but probably poorly control the IBS symptom complex. Loperamide is superior to placebo in improvement of diarrhoea but not abdominal pain in IBS. Tegaserod is a well- tolerated aminoguanidine indole derivative of serotonin that is a partial 5HT4-receptor agonist with prokinetic properties; a therapeutic gain over placebo of 5% to 15% has been observed in constipation-predominant IBS in females. Alosetron is a 5HT3-receptor antagonist that is efficacious in females with diarrhoea-predominant IBS, with a 12% to 17% therapeutic gain; the risk of ischaemic colitis is 1 in 350, with very severe constipation occurring in about 1 in 1000. Optimizing study design remains a challenge in IBS. New visceral analgesic and motility modifying agents, as well as anti-inflammatory agents are in trials, and hopefully additional efficacious therapeutic options for patients with IBS will soon emerge.
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PMID:Evaluation of drug treatment in irritable bowel syndrome. 1296 80

Tegaserod is a new partial agonist of serotonin 5-HT4 receptors specifically developed for the treatment of nondiarrhoeal forms of irritable bowel syndrome (IBS). Among its various effects is the stimulation of the peristaltic reflex with its promotility action appearing to affect the whole length of the gastrointestinal tract. Tegaserod has been assessed in a number of international multicentre trials and its use leads to an improvement in abdominal pain and bowel dysfunction as well as global well-being, at the expense of remarkably few adverse effects. It is noteworthy that it also appears to improve bloating, a benefit that has not been previously reported for a medication used in IBS. The optimal dose is 6 mg twice daily and the advantage of tegaserod over placebo in different trials varies from 5-20% with the number needed to treat ranging from 5-15 depending on the time at which this effect is calculated during the course of a trial. Recent experience with other drugs acting on 5-HT receptors has focused attention on possible safety issues such as prolongation of the QTc interval on the electrocardiogram and ischaemic colitis. However, data from efficacy trials and studies specifically designed to address the safety of tegaserod have not revealed any evidence of cardiotoxicity or the potential for causing ischaemic colitis. Furthermore, investigation of possible interactions with other drugs such as warfarin or the oral contraceptive have not resulted in any prescribing restrictions. Inappropriate prescription of tegaserod to a subgroup of IBS patients for which the drug was not designed, does not appear to have any serious consequences. Most of the efficacy data on tegaserod has been accumulated in females, simply as a result of the failure to recruit adequate numbers of males or restriction of trials to females. There is therefore insufficient information to assess whether there might be any potential gender differences in responsiveness. For this reason, the drug is currently only licensed for use in females.
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PMID:Benefit-risk assessment of tegaserod in irritable bowel syndrome. 1500 35


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