Acitrom is the brand name of a medicine called nicoumalone. Coumadin contains warfarin. Both nicoumalone and warfarin are quite similar and belong to the coumarin group of drugs. In Canada and UK, nicoumalone (sold under the brand names of Sintrom and Sinthrome) is widely used while in USA, warfarin is in vogue.
You can use any one of the two agents.