We disclose a composition comprising an echogenic liposome (ELIP) having an exterior surface, an interior surface, and at least one bilayer comprising at least one lipid selected from the group consisting of saturated phospholipids, unsaturated phospholipids, mixed phospholipids, and cholesterol, and a thrombolytic compound trapped by the ELIP. We also disclose a method of treating a medical condition in a patient characterized by a thrombus in the patient's vasculature, comprising administering to the patient the composition in an amount effective to reduce the size of the thrombus.