Ranitidin Versus Omeprazole in Patients Taking Clopidogrel
Ranitidin Versus Omeprazole in Patients Taking Clopidogrel
Previous reports have shown a possible drug interaction between clopidogrel and proton pump
 inhibitors (PPI´s), which could result in increased number of adverse cardiovascular events
 among patients on dual antiplatelet therapy(DAPT). Because of this, ranitidin has been
 proposed as an alternative drug to PPI´s for prophylaxis of gastrointestinal bleeding in
 patients who need DAPT. The study´s aim is to test the hypothesis that ranitidin doesn´t have
 any influence on clopidogrel pharmacodynamic.
Study population: 100 patients with Stable Coronary Artery Disease from Heart Institute

 Inclusion Criteria:

 -  Age > 18 years old

 -  Coronary artery disease, defined as previous myocardial infarction and/or coronary
 angioplasty and/or Coronary Artery Bypass Graft (CABG) surgery and/or coronariography
 showing obstruction of at least 50 % in one of major epicardial vessels

 -  Treatment with Acetylsalicylic Acid (ASA) 100 mg/day

 Exclusion Criteria:

 -  Use in the last 7 days of oral anticoagulant or any other antiplatelet drug beside ASA

 -  Previous utilization of PPI or ranitidine in the last 7 days before randomization

 -  Active bleeding

 -  Pregnancy or woman of childbearing age without contraceptive method

 -  Hemoglobin < 10 g/dL or hematocrit < 30 %, hematocrit > 50 %, platelets < 100.000/mm3 or
 > 500.000/mm3; creatinin clearance < 50 ml/minute

 -  Percutaneous coronary intervention (PCI) on the last 30 days before randomization (or
 PCI on the last year when drug-eluted stents are used); CABG surgery on the last 90
 days; acute coronary syndrome on the last 60 days

 -  Active malignant neoplasm

 -  Active peptic ulcer disease on the last 60 days or upper gastrointestinal bleeding any
 time in life

 -  Known allergy to the drugs clopidogrel, ranitidine or omeprazole

 -  Refuse to participate in the study]

 Methodology: The study has a double-blind, double-dummy prospective design. Clopidogrel
 action is evaluated by platelet function tests: VerifyNow, bioimpedance aggregometry and
 Platelet Function Analyzer-100 (PFA-100). The patients have measurements of platelet function
 on three moments: before starting clopidogrel; 1 week after DAPT with clopidogrel (without
 loading dose) plus ASA; and after 1 week of randomization to ranitidin 150 mg bid or
 omeprazole 20 mg bid.
Inclusion Criteria:

 -  Age > 18 years old

 -  Coronary artery disease, defined as previous myocardial infarction and/or coronary
 angioplasty and/or CABG surgery and/or coronariography showing obstruction of at least
 50 % in one of major epicardial vessels

 -  Treatment with Acetylsalicylic Acid (ASA) 100 mg/day

 Exclusion Criteria:

 -  Use on the last 7 days of any other antiplatelet drug beside ASA or oral anticoagulant

 -  Previous utilization of PPI or ranitidine in the last 7 days before randomization

 -  Any active bleeding

 -  Pregnancy or woman of childbearing age without contraceptive method

 -  Hemoglobin < 10 g/dL or hematocrit < 30 %, hematocrit > 50 %, platelets < 100.000/mm3
 or > 500.000/mm3; creatinin clearance < 50 ml/minute

 -  Percutaneous coronary intervention (PCI) on the last 30 days before randomization (or
 PCI on the last year when drug-eluted stents are used); CABG surgery on the last 90
 days; acute coronary syndrome on the last 60 days

 -  Active malignant neoplasm

 -  Active peptic ulcer disease on the last 60 days or upper gastrointestinal bleeding any
 time in life

 -  Known allergy to the drugs clopidogrel, ranitidine or omeprazole

 -  Refuse to participate in the study