Pharmacology General bcad8e3e Which of the following statements is not true for heparin - A Acts by activating anti-thrombin III B Protamine sulphate antagonizes its action C Requires aPTT monitoring in patient D Has only in vivo anticoagulant action High-Yield Explanation Ans. is 'd' i.e., Has only in vivo anticoagulant action o Heparin has action both in vitro and in vivo.