The criteria for inclusion/exclusion in the study are as follows
| Entry criteria | Exclusion criteria |
| Caribbean Hispanics residing in Puerto Rico | Non-Hispanic patients |
| Both genders (males/females) | Currently enrolled in another active research protocols |
| Age ≥21 years old | Blood Urea Nitrogen (BUN) >30 and creatinine >2.0 mg/dL |
| Receiving clopidogrel (75 mg/day) for therapeutic indications | Platelet count < 100 x 109/L |
| No clinically active hepatic abnormality | Haematocrit ≤25% |
| The ability to understand the requirements of the study | Nasogastric or enteral feeding |
| The ability to comply with study procedures and protocol | Acute illness (eg, sepsis, infection, anaemia), active malignancy |
| A female patient is eligible to enter the study if she is of childbearing potential but not pregnant or nursing, or not of childbearing potential | HIV/AIDS, hepatitis B, sickle cell patients |
| Alcoholism and drug abuse | |
| Patients with any cognitive and mental health impairment | |
| Patients taking another antiplatelet |