Abstract: The present invention relates to chitosan nitrate for use as nitric oxide donor, in particular for use in the prevention or treatment of a condition related to NO deficiency in mammals, preferably humans. Suitable conditions to be treated with chitosan nitrate include disorders related to the skin, conditions related to sexual dysfunction, conditions wherein there is a need for pain treatment, conditions being a disorder related to the eyes, nose and sinus, conditions being a disorder related to the airways, conditions related to a gastro-intestinal disorder, and conditions being a metabolic disorder. These conditions were successfully treated or reduced by the application of chitosan nitrate according to the present invention. The invention also concerns a non-therapeutic or cosmetic method for skin protection and/or for healthy aging.