Thromboembolic prophylaxis must be provided for patients according to their
individual risk profile (low, medium, high). After thrombotic events a met
iculous record of all congenital and acquired risk factors is vital. The th
romboembolic risk must be evaluated before initiating any in- or outpatient
treatment since the examination findings and medical history will dictate
customised therapeutic consequences in terms of the choice, duration and in
tensity of anticoagulation in addition to physical therapy. The high risk o
f reoccurrence must be remembered in patients with both congenital and acqu
ired thrombophilic conditions. Patients must be carefully advised before or
when beginning treatment. They must be informed of the various side effect
s and uses of low molecular heparins and coumarin derivatives.