The mechanism of action of esomeprazole is a weak base, which becomes an active form in the highly acidic environment of the secretory canaliculi of the parietal cells of the gastric mucosa and inhibits the proton pump – enzyme what is trenbolone acetaten this is inhibited both basal and stimulated acid secretion. The effect on the secretion of hydrochloric acid in the stomach. Step esomeprazole develops within 1 hour after oral administration of 20 mg or 40 mg. When taking the drug daily for 5 days in a dose of 20 mg once daily average maximum concentration of hydrochloric acid is reduced after stimulation of pentagastrin by 90% (as measured by the acid concentration in 6-7 hours after drug administration on 5th day of therapy).
In patients with gastroesophageal reflux disease (GERD) and the presence of clinical symptoms after 5 days of daily oral administration of esomeprazole 20 mg or 40 mg of intragastric pH value above 4 was maintained for an average of 13 and 17 hours from 24 hours. The correlation between the concentration of drug in plasma and the inhibition of acid secretion (to assess concentration used AUC parameter (area under the curve. “Concentration – time”) Therapeutic effect achieved by inhibiting the secretion of hydrochloric acid. Upon receiving Nexium 40mg healing reflux oesophagitis occurs in approximately 78% of patients after 4 weeks of therapy and 93% – after 8 weeks of therapy. Neksium Treatment of 20 mg 2 times a day in combination with appropriate antibiotics for one week results in successful eradication of Helicobacter pylori in approximately 90% of patients. patients with uncomplicated ulcer after a week of eradication of the course does not require subsequent monotherapy, lowering the secretion of gastric glands, for the healing of ulcers and relief of symptoms. The efficacy of what is trenbolone acetatebleeding from peptic ulcers has been shown in a study of patients with bleeding peptic ulcer confirmed endoscopically. Other effects associated with the inhibition of gastric acid secretion. during treatment, drugs that lower the secretion of gastric glands, the concentration of gastrin in plasma increased by reducing acid secretion. The concentration of chromogranin A (CgA) increases due to the reduction of secretion of hydrochloric acid. Increased CgA concentration may influence the results of inspections to detect neuroendocrine tumors.To prevent this effect of therapy with proton pump inhibitors to pause for 5-14 days prior to the survey CgA concentration. If during this time the concentration of CgA not returned to normal, the survey must be repeated.
For children and adult patients treated with esomeprazole long time, there is an increase amount enterochromaffin cells, probably related to an increase in plasma gastrin concentrations. The clinical significance of this phenomenon is not. Patients taking drugs that lower the secretion of gastric glands, over a long period of time, often marked the formation of glandular cysts in the stomach. These phenomena are caused by physiological changes as a result of pronounced inhibition of acid secretion. The cysts are benign and regress. The use of drugs suppressing the secretion of hydrochloric acid in the stomach, including proton pump inhibitors, accompanied by an increase in stomach content microbial flora normally present in the gastrointestinal tract. The use of proton pump inhibitors can cause a slight increase in risk of infectious diseases of the gastrointestinal tract caused by bacteria of the genus Salmonella spp. , And Campylobacter spp. and, in hospitalized patients, probably, of Clostridium difficile-. In two comparative studies with ranitidine Nexium showed better efficacy in healing of gastric ulcers in patients treated with non-steroidal anti-inflammatory drugs (NSAIDs), including selective cyclooxygenase-2 (COX-2) . in two studies Nexium showed high efficacy in the prevention of gastric and duodenal ulcers in patients treated with NSAIDs (age group older than 60 years and / or peptic ulcer history), including selective COX-2 inhibitors.
Pharmacokinetics Absorption and distribution. Esomeprazole is unstable in an acidic environment, so for oral administration, tablets containing granules of the drug, which shell is resistant to gastric juice.Under conditions in vivo , only a small portion is converted into esomeprazole R-isomer. The drug is rapidly absorbed: the maximum plasma concentration is reached after 1 to 2 hours after ingestion. The absolute bioavailability after a single dose of esomeprazole 40 mg dose is 64% and increases to 89% on a daily administration once daily. To what is trenbolone acetate 20 mg of esomeprazole, the figures are 50% and 68%, respectively. The volume of distribution at equilibrium concentrations in healthy people is about 0.22 l / kg body weight. Esomeprazole is bound to plasma proteins by 97%. Food intake slows down and reduces the absorption of esomeprazole in the stomach, but it has no significant effect on the efficiency of inhibition of gastric acid secretion. Metabolism and excretion. Esomeprazole is metabolized with participation of cytochrome P450. The main part is metabolized with the participation of a specific polymorphic isoenzyme CYP2C19, at the same time form the hydroxylated metabolites of esomeprazole and desmetilirovannye. The metabolism of the remaining part made of CYP3A4 isoenzyme; thereby forming a sulfonic acid esomeprazole, which is the principal metabolite determined in plasma. The parameters listed below reflect mainly character pharmacokinetics in patients with elevated isoenzyme CYP2C19. The total clearance is approximately 17 l / h after a single dosing and 9 l / h – after repeated administration. The half-life of 1.3 hours in a systematic administered once a day. The area under the curve “concentration-time» (AUC) increases with repeated reception of esomeprazole. Dose-dependent increase in AUC Repeated dose of esomeprazole is not linear, that is a consequence of the reduced metabolism in the “first pass” through the liver, as well as a decrease in systemic clearance probably caused by inhibition of isoenzyme CYP2C19 esomeprazole and / or sulfonic acid. When taken daily once daily esomeprazole completely eliminated from the plasma in the interval between doses and accumulates. The major metabolites of esomeprazole have no effect on gastric acid secretion. When administered orally to 80% of the dose is excreted as metabolites in the urine, the remainder is excreted in the faeces. The urine is detected less than 1% of unchanged esomeprazole. Pharmacokinetics in some groups of patients. Approximately 2,9 ± 1,5% of the population is reduced activity of CYP2C19 isoenzyme. In such patients, esomeprazole metabolism, mainly carried out by the action of CYP3A4. At regular reception esomeprazole 40 mg once daily average AUC value 100% higher than this value in patients with elevated isoenzyme CYP2C19. Mean values of maximum plasma concentrations in patients with decreased isoenzyme activity increased by about 60%. These features do not affect the dose and mode of administration of esomeprazole. Elderly patients (71-80 years), the metabolism of esomeprazole is not undergoing significant changes. After a single dose of 40 mg esomeprazole the mean value of AUC in women by 30% higher than that of men. With daily taking the drug once a day differences in the pharmacokinetics of males and females were observed. These features do not affect the dose and method of administration of esomeprazole. In patients with mild to moderate hepatic insufficiency, the metabolism what is trenbolone acetate of esomeprazole may be violated. In patients with severe liver failure metabolic rate is reduced, which increases the AUC value for esomeprazole 2 times. Study of pharmacokinetics in patients with renal failure has not been conducted. Since excretion through the kidneys is carried out is not of esomeprazole and its metabolites, it is believed that the metabolism of esomeprazole is not changed in patients with renal insufficiency. Children between the ages of 12-18 years after the repeated administration of 20 mg and 40 mg esomeprazole the AUC and time to maximum concentration (t max ) was similar with the values of t and AUC in plasma max adults. usa steroids c4 pharmaceuticals buy steroid pills online