THE PRESENT INVENTION REFERS TO A COMPOSITION, COMPRISING HEMOGLOBIN OR MYOGLOBIN, WHEREIN IN AT LEAST 40% OF SAID HEMOGLOBIN OR MYOGLOBIN THE OXYGEN BINDING SITE IS CHARGED BY A NON-O2 LIGAND, AND AT LEAST ONE FURTHER INGREDIENT, A METHOD FOR PREPARING SAID COMPOSITION AND THE USE OF HEMOGLOBIN OR MYOGLOBIN CHARGED WITH A NON-OXYGEN LIGAND FOR EXTERNAL TREATMENT OF WOUNDS.