RT Journal Article SR Electronic T1 Intravenous anticoagulants: heparin and ancrod JF Drug and Therapeutics Bulletin JO Drug Ther Bull FD BMJ Publishing Group Ltd SP 29 OP 30 DO 10.1136/dtb.10.8.29 VO 10 IS 8 YR 1972 UL http://dtb.bmj.com/content/10/8/29.abstract AB Much more is known about heparin now than when we discussed it six years ago.1 It is a difficult drug to use, and is frequently prescribed too casually. Another intravenous anticoagulant, arvin, has been developed, and needs to be compared with heparin.