Modified chitosan hemostatic agents include reverse micelles (10) having an outer hydrophobic shell (12) of suitable biocompatible hydrophobic components such as alkanes, and hydrophilic positively charged chitosan moieties (14) enclosed within the hydrophobic shell (12). The hydrophobic shell (12) may be formed by attaching hydrophobic moieties to one end of chitosan polymer molecules while retaining sufficient reactive (positively charged) amine groups on the remainder of the chitosan polymers for effective blood clotting. The resulting reverse micelles (10) have the capability of penetrating mucous membranes such as nasal mucosa (20) or otherwise penetrating to bleed sites shielded or partially shielded by mucosa or other tissues. Upon exposure to red blood cells (24) escaping from the bleed site (26) the positively charged interior of the reverse micelles breaks through the hydrophobic shell (12) to combine with the negatively charged red blood cells (24) thereby clotting and attenuating or stopping the bleeding.
