Aspirin Blood Level, Proton Pump Inhiditor Treatment
Conditions
Keywords
pharmacokinetics, aspirin, proton pump inhiditor
Brief summary
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.
Interventions
DRUGaspirin and omeprazole
aspirin 100 mg, once daily aspirin 100 mg and omeprazole 20 mg both once daily.
Sponsors
Assaf-Harofeh Medical Center
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
No
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.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Aspirin Level in Blood (Area Under the Curve) | on day 7,on day 21 | 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. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Platelet Function Tests | on day 0 as a baseline and on day 7 and 21 of the study. | 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. |
Countries
Israel
Participant flow
Recruitment details
healthy volunteers were recruted on march 2007. all of the patients are co-workers in the department of medicine in assaf harofeh medical center.
Pre-assignment details
one volunteer was excluded before enrollment due to recent consumption of NSAIDS
Participants by arm
| Arm | Count |
|---|---|
| Aspirin Then Aspirin Plus Omeprazole 7 days of Aspirin (100mg) alone, followed by 14 days of Aspirin and Omeprazole (20mg BID for 3 days and then 20mg once daily | 9 |
| Total | 9 |
Baseline characteristics
| Characteristic | Aspirin Then Aspirin Plus Omeprazole |
|---|---|
| Age, Categorical <=18 years | 0 Participants |
| Age, Categorical >=65 years | 0 Participants |
| Age, Categorical Between 18 and 65 years | 9 Participants |
| Age Continuous | 39.3 years STANDARD_DEVIATION 12.5 |
| Sex: Female, Male Female | 2 Participants |
| Sex: Female, Male Male | 7 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | — / — |
| other Total, other adverse events | 1 / 9 |
| serious Total, serious adverse events | 0 / 9 |
Outcome results
Primary
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.
Time frame: on day 7,on day 21
Population: 9 volunteers completed the study, one volunteer was excluded from pharmacokinetics, because serum salicylic acid concentration was not at the baseline (non-detectable) in the 0-hour sample.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Aspirin Then Aspirin Plus Omeprazole | Aspirin Level in Blood (Area Under the Curve) | aspirin area under the curve on day 7 | 49.4 mg*hour/mL | Standard Deviation 13.5 |
| Aspirin Then Aspirin Plus Omeprazole | Aspirin Level in Blood (Area Under the Curve) | aspirin area under the curve on day 21 | 50.7 mg*hour/mL | Standard Deviation 15.3 |
| Aspirin Then Aspirin Plus Omeprazole | Aspirin Level in Blood (Area Under the Curve) | 1 hour after admission day 7 (aspirin alone) | 8.7 mg*hour/mL | Standard Deviation 4 |
| Aspirin Then Aspirin Plus Omeprazole | Aspirin Level in Blood (Area Under the Curve) | 1 hour after admission day 21 (aspirin+omeprazole) | 6.5 mg*hour/mL | Standard Deviation 4.1 |
Secondary
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.
Time frame: on day 0 as a baseline and on day 7 and 21 of the study.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Aspirin Then Aspirin Plus Omeprazole | Platelet Function Tests | day 0 | 80 percent | Standard Deviation 4.18 |
| Aspirin Then Aspirin Plus Omeprazole | Platelet Function Tests | day 7 | 8.55 percent | Standard Deviation 2.45 |
| Aspirin Then Aspirin Plus Omeprazole | Platelet Function Tests | day 21 | 8.77 percent | Standard Deviation 2.38 |