An aqueous formulation of argatroban and of related compounds is disclosed along with a reconstitutable formulation, each of which is substantially, if not totally alcohol free. The formulations are also substantially free, if not totally free, of mono-, di-, and oligo-saccharides. An especially preferred embodiment is a ready-to-administer 1 mg/ml injectable dosage form having argatroban, lactobionic acid, and methionine.