Using a C1 inhibitor for preventing ischemia-reperfusion injury.

Use of a C1 inhibitor has a reduced residue level of terminal sialic acids compared with human C1 inhibitor derived from plasma, where the reduced level of residues of sialic acids terminals results in a half life of less than 6 hours plasma, in the preparation of a pharmaceutical composition for the prevention, reduction or treatment of at least one of ischemia and reperfusion injury, wherein the C1 inhibitor is administered at least 10 minutes after the ischemia period and / or the onset of reperfusion.