As a 20% solution, Ferric Sulphate is a coagulative and hemostatic agent which forms ferric ion-protein complex on contact with blood. It seals the damaged vessels mechanically, thus producing hemostasis, and the capillary orifices are occluded by the agglutinated protein complex, which prevents blood clot formation. It causes a local and reversible inflammatory response to the oral soft tissues. The, recommended application time is 1?3 min, and should be placed , directly against the damaged tissue, due to its quick action. Solutions of Ferric Sulphate above 20% are highly acidic and may cause considerable tissue irritation and postoperative root sensitivity.