Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022104 (irritable bowel syndrome)
 8,033 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Prokinetic agents are currently being investigated as potential therapies for motility disorders of the lower gastrointestinal tract. Cholinergic agonists such as bethanechol are known to improve postoperative ileus but are limited because of side effects. Dopamine antagonists such as domperidone appear to have maximal prokinetic effect in the proximal gastrointestinal tract and are effective for such conditions as gastroparesis and gastroesophageal reflux, but they appear to have little physiologic effect in the colon or in colonic motility disorders. Naloxone, an opioid antagonist, appears to hold promise in patients with irritable bowel syndrome, small intestinal pseudo-obstruction, and constipation. Erythromycin exerts its prokinetic effect by acting as a motilin agonist; it has been used in the treatment of diabetic gastroparesis and appears to improve symptoms of colonic pseudo-obstruction and postoperative ileus. Metoclopramide, a combined cholinergic agonist and dopamine antagonist, is currently used exclusively for proximal motility dysfunction. Cisapride appears to hold the most promise for patients with colonic motility disorders. In patients with postoperative ileus, cisapride is associated with an increased return of bowel function compared with placebo. In patients with chronic constipation, cisapride increases stool frequency and decreases laxative abuse in both adults and children. Hopefully, as an understanding of gastrointestinal motility increases, effective prokinetic agents will be developed that will improve symptoms of patients with large bowel motility disorders and may also help to predict those patients who benefit from surgical management for constipation.
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PMID:Prokinetic agents for lower gastrointestinal motility disorders. 813 79

Functional (nonulcer) dyspepsia refers to upper abdominal pain or discomfort with or without symptoms of early satiety, nausea, or vomiting with no definable organic cause. The current Rome II criteria help to diagnose functional dyspepsia and avoid misdiagnosis of gastroesophageal reflux disease and irritable bowel syndrome as functional dyspepsia. Assessment of gastric emptying with scintigraphy or breath testing may be useful in identifying delayed gastric emptying in patients with dyspeptic symptoms and may be helpful in patient management. Electrogastrography is a noninvasive test that evaluates for gastric dysrhythmias. Satiety testing is being evaluated as an indirect test for impaired fundic relaxation and visceral hypersensitivity. The symptom response to Helicobacter pylori therapy in patients with functional dyspepsia and a negative endoscopy examination but a positive H. pylori test is marginal. Lifestyle modifications often are suggested for initial treatment of functional dyspepsia. Dietary changes such as frequent small meals, low-fat diet, and avoidance of certain aggravating foods may improve symptoms. Additional measures include cessation of smoking, avoiding excess alcohol intake, and minimizing coffee intake. Antacids and over-the-counter histamine type 2 receptor antagonists may be helpful as an "on-demand" therapy for intermittent symptoms. They are safe and relatively inexpensive. Different subgroups of functional dyspepsia are based on the predominant symptom and may help in choosing an appropriate drug to initiate therapy. If the predominant symptom is epigastric pain (ulcer-like functional dyspepsia), histamine-2 receptor antagonists or proton pump inhibitors are the initial treatment of choice. If fullness, bloating, early satiety or nausea is the predominant complaint (dysmotility-like functional dyspepsia), a prokinetic agent may help. Metoclopramide is the only available effective prokinetic agent at present. If metoclopramide is used, short-term treatment and discussion of possible side effects with the patient are advised. If there is no response to these initial treatments, switching therapy from proton pump inhibitor to prokinetic or vice versa can be tried. If these treatment options fail, patient re-evaluation for other disorders (including other functional bowel disorders) is advised. A low-dose tricyclic antidepressant at bedtime may be helpful for treatment of visceral hypersensitivity.
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PMID:Functional (Nonulcer) Dyspepsia. 1187 96

A middle-aged woman was referred under the 2-week urgent brain cancer initiative following the finding of a raised serum prolactin level. The patient had been taking metoclopramide on a daily basis to aid her symptoms of irritable bowel syndrome. The raised prolactin level had led to oligomenorrhoea prompting her general practitioner (GP) to check pituitary hormone levels.Metoclopramide is a potent dopamine antagonist and dopamine acts as the physiological inhibitor of prolactin synthesis. Thus, the dopamine antagonism led to elevated prolactin level and the symptom of oligomenorrhoea.Following curtailment of the metoclopramide, the prolactin level normalised very quickly and the patient was reassured.Consideration should be given to non-pathological causes of hyperprolactinaemia, including physiological states such as pregnancy and concurrent medication.
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PMID:Pharmacological hyperprolactinaemia. 2214 Apr 13