• Rapid-acting anticoagulant fast-acting, has a short half-life Uses: • Pulmonary embolism (PE), Stroke evolving, Massive deep venous thrombosis (DVT) Sources: ✓Lungs of cattle, Intestines of pigs Adverse effects • Hemorrhage, Thrombocytopenia, Hypersensitivity, Protamine Sulfate as antidote, Activated partial thromboplastin time IT NEEDS MONITORING w/ SPECIAL BLOOD TESTS