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Query: UMLS:C0017168 (gastroesophageal reflux disease)
 11,783 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A questionnaire was constructed and validated to improve the accuracy of symptom assessment in diagnosing gastro-oesophageal reflux disease (GERD). The GERD questionnaire consisted of four questions describing an upward moving, uncomfortable feeling in the chest frequently accompanied by retrosternal burning that is improved with antacids. It was found that if a patient answered yes to all four questions the likelihood was 85% that erosive oesophagitis would be detected on endoscopy or that pathological gastro-oesophageal reflux on 24-hour pH-monitoring would be documented, or both. The GERD questionnaire was used to identify 269 patients with probable GERD who after one week on placebo entered a 2-week double-blind placebo-controlled study which was completed by 251 patients. Cimetidine (400 mg) b.d. was given to 124 patients and placebo to 127 patients. On diary cards the patients noted the number, the mean duration and the mean severity of GERD symptoms episodes. Cimetidine was significantly superior to placebo in increasing the percentage of symptom-free days, and in reducing the median number of daily symptom episodes. This trial demonstrates that 400 mg cimetidine b.d. is effective in improving GERD symptoms in patients identified by a descriptive, validated GERD questionnaire.
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PMID:Cimetidine improves GERD symptoms in patients selected by a validated GERD questionnaire. 843 41

Gastro-oesophageal reflux disease (GORD) is a very common disorder of upper gastro-intestinal motility, differing widely in severity and prognosis. Medical therapy of GORD has involved antacids, alginates, prokinetic agents and antisecretory compounds, primarily H2 receptor antagonists and proton pump inhibitors. Knowledge of the pharmacokinetics of these compounds is important, to optimise the therapeutic benefit in each patient. GORD patients are often elderly and pharmacokinetics are move variable in this group. Furthermore, they often suffer from other diseases needing medical therapy and may need a combination of drugs to heal reflux oesophagitis and relieve reflux symptoms. The ideal therapy for GORD will have linear pharmacokinetics, a relatively long plasma half-life (t1/2), a duration of action allowing once daily administration, and a stable effect independent of interactions with food, antacids and other drugs. Over-the-counter antacids and alginates are widely used, buy may affect absorption of H2 receptor antagonists like cimetidine and ranitidine. Aluminium-containing antacids may, over time, cause toxicity in patients with renal insufficiency. In the treatment of GORD, cisapride presents important advantages over earlier prokinetic compounds, with a longer plasma t1/2, low penetration of the blood-brain barrier and fewer adverse effects. The group of H2 receptor antagonists is still the most frequently use therapy for GORD. Linear pharmacokinetics make dose adjustments easy and safe. In individual patients, suppression of gastric secretion is related to the area under the plasma concentration-time curve (AUC), but there is wide interindividual variation in the effect of the same oral dose. Only with frequent administration and high doses will acid suppression approximate that of proton pump inhibitors. Tolerance, with loss of effect over time, however, is most pronounced in this situation. H2 receptor antagonists seem well suited for on-demand treatment of reflux symptoms, due to the rapid onset of effect and a decrease likelihood of the development of tolerance. Effervescent formulations provide more rapid absorption and almost immediate clinical effect. Cimetidine, however, causes interference with the metabolism of several other drugs in common use. In elderly patients elimination is delayed and in patients with renal insufficiency, dose reductions of all H2 receptor antagonists are recommended. The most effective medical therapy for any severity of GORD, particularly in severe oesophagitis, are the proton pump inhibitors. The substituted benzimidazoles (omeprazole, lansoprazole and pantoprazole), are prodrugs which once trapped and activated in the acid milieu of the gastric glands potently suppress gastric secretion of acid and pepsin. Their long duration of action, more related to the slow turnover of parietal cell H(+)-K+ ATPase molecules, allows once daily administration in most patients. Interindividual variation in bioavailability sometimes calls for higher doses or twice daily administration. Acid suppression is closely related to the AUC. Omeprazole is prone to interaction with the metabolism of other drugs, some of which may e be clinically important. Lansoprazole seems to have an earlier onset of action than omeprazole, ascribed to higher bioavailability during the first days of treatment. Proton pump inhibitors have a slow onset of action, which makes them unsuited for on-demand therapy. Clinical practice in GORD calls for the use of not one but several substances, according to the severity and symptom pattern of the patient. Pharmacokinetic optimisation in the treatment of GORD is a question of selecting the most suitable substances and administration schemes within each group. Cisapride is superior to other prokinetics in terms of longer plasma t1/2 and less toxicity. Amongst H2 receptor antagonists, the more long-acting compounds, ranitidine and famotidine, will improve acidity control througho
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PMID:Pharmacokinetic optimisation in the treatment of gastro-oesophageal reflux disease. 911 86

Gastro-oesophageal reflux disease is probably the most common acid-peptic disease in Western countries, and the successful treatment of mild to moderate disease with pharmacotherapy has become commonplace. A large number of effective drugs are now available, and so the decision-making process for physicians increasingly relies on considerations other than pure efficacy. Cost, adverse effects and drug interactions have therefore become important, particularly in the most vulnerable patients - children, the elderly and patients who are ill and are taking medications that may influence the efficacy of antireflux therapy. Important drug interactions with antacids include the prevention of the absorption of antibacterials such as tetracycline, azithromycin and quinolones. H2 antagonists, proton pump inhibitors and prokinetic agents undergo metabolism by the cytochrome P450 (CYP) system present in the liver and gastrointestinal tract. Cimetidine is an inhibitor of CYP3A and it may cause significant interactions with drugs of narrow therapeutic range and low bioavailability that are metabolised by these enzymes. The gastroparietal proton pump inhibitors lansoprazole, omeprazole and pantoprazole are all primarily metabolised by a genetically polymorphic enzyme, CYP2C19, that is absent from approximately 3% of Caucasians and 20% of Asians. These drugs may also interact with CYP3A, but to a lesser extent. Interactions with prokinetic agents carry the greatest potential for harm. Metoclopramide is a dopamine antagonist that may cause extrapyramidal effects when administered alone at high concentrations, or when coadministered with antipsychotic agents such as haloperidol or phenothiazines. Cisapride is clearly able to prolong the electrocardiographic QT interval and cause lethal ventricular arrhythmias when its metabolism is slowed by interaction with inhibitors of CYP3A, such as erythromycin, ketoconazole or itraconazole.
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PMID:Selection of drugs to treat gastro-oesophageal reflux disease: the role of drug interactions. 1106 15

Gastroesophageal reflux (GOR) is a major cause of morbidity and failure to thrive particularly in neurologically impaired children. Clinical manifestations of GOR in children range from regurgitation, food refusal, irritability, failure to thrive, hematemesis, wheezing and aspiration pneumonia, apnoea and apparent life threatening events in infants to clinically silent reflux. Although, no one test is always best to diagnose GOR, 24 hour esophageal pH monitoring remains the 'gold standard' for diagnosis. Barium radiography is useful for the diagnosis of associated anatomical abnormalities and endoscopy enables a histological diagnosis of esophagitis. Therapy for gastroesophageal reflux disease is now well established. Proper positioning of the baby and thickening of feeds is beneficial in uncomplicated GOR. Prokinetic agents like cisapride should be tried if dietary management and antacids are ineffective. Metoclopramide or domperidone may be tried in neurologically impaired children. H2-receptor antagonists are indicated in GOR complicated by esophagitis. Ranitidine is regarded to be more potent. Cimetidine has additional spectrum of adverse effects and sufficient information is not available on famotidine. Omeprazole has been shown to be effective in treating GOR-esophagitis resistant to H2 antagonist therapy even in high risk patients.
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PMID:Gastroesophageal reflux in children. 1113 70

Histamine-2 receptor antagonists are a class of drugs used to treat the acid-related gastrointestinal diseases such as ulcer and gastro-oesophageal reflux disease. Although such drugs, especially ranitidine and famotidine, are still widely used, their effects on semen quality, and hence on male infertility, is still unclear. This MiniReview systematically addresses and summarizes the effect of histamine-2 receptor antagonists (cimetidine, ranitidine, nizatidine and famotidine) on semen quality, particularly, on sperm function. Cimetidine appears to have adverse effects on semen quality. While the effects of ranitidine and nizatidine on semen quality are still controversial, famotidine does not appear to change semen quality. Therefore, additional studies will be required to clarify whether histamine-2 receptor-independent effects of these drugs play a role in semen quality as well as further clinical studies including direct comparison of the histamine-2 receptor antagonists.
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PMID:Histamine-2 Receptor Antagonists and Semen Quality. 2617 90


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