omeprazole is an inhibitor of H+ K+ ATPase. This medication inhibits the activity of H+-K+-ATPase in gastric parietal cells and thus blocks the final stage of hydrochloric acid secretion. This leads to a reduction in basal and stimulated secretion, regardless of the nature of the stimulus. Due to the reduction of acid secretion omeprazole reduces or normalizes the effects of acid in the esophagus in patients with reflux esophagitis.
omeprazole has a bactericidal effect on Helicobacter pylori. Eradication of H. pylori when omeprazole used with antibiotics allows to quickly arrest the symptoms, to take a high degree of healing of damaged mucosa and persistent long-term remission and reduce the likelihood of bleeding from the gastrointestinal tract.
After oral administration omeprazole is rapidly absorbed from the gastrointestinal tract. This drug penetrates the parietal cells of gastric mucosa. Plasma protein binding is about 95% (predominantly albumin). omeprazole is biotransformed in the liver. Excreted by the kidneys - 72-80%, in the faeces - about 20%. T1/2 is 0.5-1 h. In patients with chronic liver diseases T1/2 increases up to 3 hours.
Why is omeprazole prescribed?
Gastric ulcer and duodenal ulcer in acute phase (including associated with Helicobacter pylori), reflux esophagitis, Zollinger-Ellison syndrome, erosive and ulcerative lesions of gastric and duodenal ulcers associated with taking NSAIDs.
Dosage and administration
The dosing regimen of omeprazole is individual. When this medication is administered orally of the single dose is 20-40 mg. The daily dose is 20-80 mg, the frequency of use is 1-2 times / day. The duration of treatment is 2-8 weeks.
omeprazole side effects, adverse reactions
Digestive system: rarely - nausea, diarrhea, constipation, abdominal pain, flatulence.
CNS: rarely - headache, dizziness, weakness.
Hemopoietic system: in some cases - anemia, eosinopenia, neutropenia, thrombocytopenia.
Urinary system: in some cases - hematuria, proteinuria.
Musculoskeletal system: in some cases - arthralgia, muscle weakness, myalgia.
Allergic reactions: rarely - skin rash.
Chronic liver disease (including in history), hypersensitivity to omeprazole.
Using during pregnancy and breastfeeding
In the absence of clinical experience with omeprazole it is not recommended to use this drug during pregnancy. If necessary to use during omeprazole lactation it should been solve the issue of termination of breastfeeding.
Category effects on the fetus by FDA - C.
Before the treatment with omeprazole it is necessary to exclude the possibility of a malignant process (especially gastric ulcer) because omeprazole treatment can mask symptoms and delay the correct diagnosis.
Therapy with omeprazole may affects results of laboratory studies of liver and gastrin concentrations in blood plasma.
Due to lack of experience in clinical application of omeprazole this medicine is not recommended for children.
omeprazole drug interactions
This medication alters the bioavailability of any drug, absorption depends on pH (ketoconazole, iron salts, etc.). omeprazole slows down the elimination of drugs metabolized in the liver by microsomal oxidation (warfarin, diazepam, phenytoin, etc.).
omeprazole enhances the action of coumarin and diphenine, does not change - NSAIDs. This drug increases (relative) the concentration of clarithromycin in the blood; may increases the leukopenic and thrombocytopenic effects of depressants hematopoiesis drugs. Substance for intravenous infusion is compatible only with saline and dextrose (using other solvents may decrease the stability of omeprazole due to changes in pH of infusion medium).
omeprazole in case of emergency / overdose
Symptoms: dry mouth, nausea, blurred vision, headache, increased sweating, flushing, tachycardia, drowsiness, confusion.
Treatment: symptomatic, dialysis is ineffective.