In patients with protein C and protein S deficiency, when warfarin therapy is started there is a more rapid fall in concentration ... such as factor IX and X and prothrombin.

Moreover, prothrombin as well as factor V is not increased in parallel, and plasma albumin is even decreased. 15 Also, factors VII and X and the "complex" do not always move in parallel.

11,12 It has also been established that subjects may vary widely in prothrombin response to a given concentration of Dicumarol in plasma. "Sensitive" patients may exhibit marked ...