Pharmacological Study That Measures Omeprazole Effect on Aspirins Absorption in Healthy Volunteers

Study Overview
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Brief Summary
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Aspirin is a weak acid that crosses the gastric and intestinal mucosa by passive diffusion while in its lipophilic nature.Omeprazole, a proton pump inhibitor, inhibits gastric acid secretion. We assumed that omeprazole inhibits aspirin absorption, thus reducing its action on platelets. healthy volunteers, with no known peptic disease or bleeding disorders will be enrolled. All volunteers will receive 7 days of Aspirin (100mg) alone, followed by 14 days of Aspirin and Omeprazole 20mg twice daily for 3 days and then 20mg once daily. Blood levels of Aspirin will be determined by High performance liquid chromatography (HPLC), 0, 1, 2, 4, 6, 10, 24 hours after the administration of Aspirin alone on day 7 and Aspirin plus Omeprazole on day 21. Platelet function tests will be determined by platelet-rich plasma aggregometry in response to Arachidonic acid (500mg/ml), Ristocetin (1.5mg/ml) and Adenosine 5'-diphosphate (20mM) on day 0 as baseline and on day 7 and 21 of the study.

Official Title
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The Effect of Proton Pump Inhibitor (Omeprazole) on Acetosalisylic Acid Absorption.

Conditions
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Aspirin Blood Level, Proton Pump Inhiditor Treatment

Intervention / Treatment
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* Drug: aspirin and omeprazole


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: -healthy volunteers Exclusion Criteria: pretreatment with aspirin pretreatment with non steroidal anti inflamatory drugs pretreatment with antacids history of peptic ulcer disease coagulation or aggregation disorder.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Intervention/Treatment |
| --- |
|Drug: aspirin and omeprazole|aspirin 100 mg, once daily aspirin 100 mg and omeprazole 20 mg both once daily.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Aspirin Level in Blood (Area Under the Curve) | Aspirins pharmacokinetics: aspirin blood level determined by use of high performance liquid chromatography (HPLC) at baseline, 1, 2,4,6,10 and 24 hours after administration of aspirin on day 7 and on day 21. The area unther the time vs. concentration curve of the reccurent measurments(AUC) reflects bioavailability of aspirin. | on day 7,on day 21 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Platelet Function Tests | Platelet function tests were determined by optical whole blood aggregometry in response to arachidonic acid and adenosine diphosphate. the results reflects the percent of active platelets. | on day 0 as a baseline and on day 7 and 21 of the study. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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proton pump inhiditor, pharmacokinetics, aspirin