Protamine單獨給藥具有抗凝血的作用。與heparin並用，因heparin具強酸性，可與之形成穩定的鹽而失去抗凝血的作用。

Metabolism
May be partially metabolized or may be cleaved by fibrinolysin, thus freeing heparin.

Onset
Rapid, neutralization occurs within 5 min.

Duration
Duration is 2 h, dependent on body temperature.