Heparin, whose discovery was announced in 1916, is a medication used as a blood thinner. Plus, it is also used in the treatment of heart attacks and unstable angina. Basically, Heparin prevents the formation of clots and extension of existing clots within the blood. While this medication does not break down clots that have already formed, it still allows the body's natural clot lysis mechanisms to work normally to break down clots that have formed. It is worth noting that the side effects of Heparin may include bleeding, pain at the injection site, and low blood platelets. In addition, this medication has serious side effects such as heparin-induced thrombocytopenia. Bear in mind that greater care is needed in those with poor kidney function. Fortunately, though, Heparin appears to be relatively safe for use during pregnancy and breastfeeding. Remember that green leafy vegetables like broccoli, cabbage, coriander, collard greens, spinach, kale, black licorice, turnip greens, Brussels sprouts and avocados which are rich in vitamin K decrease the ability of heparin to prevent blood clotting. Plus, smoking may also decrease the effectiveness of heparin. So, make sure you stay away from tobacco products while taking this medication.