Heparins for thrombo-embolism

Heparins are anticoagulant and antithrombotic compounds that act by increasing the rate of neutralisation of factors activated by antithrombin. Standard heparins (SH), which have been used up to now in veterinary medicine, are a heterogeneous mix of molecules of a sizes. New preparations, which contain only low weight heparins (LWH), were developed because of their particular properties. LWH will be increasingly used in the future because - the risk of haemorrhage is minimised because they selectively act on factor Xa and not on coagulation factor Ha as do SH - treatment monitoring treatment easier than with SH. However, the protocols for administration of SH in dogs and cats is well established but those for LWH remain to be defined. The side-effects of LWH also need to be researched.