In 20 patients with chronic venous insufficiency and venous hypertension associated with ulcerations, the effects of a new compound, applied onto the skin (Crystacide) were assessed in a randomized, controlled study. Duplex scanning was used to assess the presence of venous obstruction and incompetence, and microcirculatory methods were used to assess and quantify venous microangiopathy and to follow up subjects after local treatment with Crystacide. Laser Doppler flowmetry (LDF) was used to assess skin perfusion in association with transcutaneous (tc) partial pressure of oxygen (PO2) measurements. Local plasma free radicals (PFR) were evaluated in the area surrounding the venous ulcer, with the D-Rom test. Crystacide was applied around and on the ulcer for 10 days. Crystacide was more effective than the control treatment: PO2 was increased, PFR and LDF were decreased (flux increase is associated with venous hypertension), and the ulcer area was significantly smaller at 10 days in the Crystacide group in comparison with the placebo group (p<0.05). In conclusion, in venous ulcerations, local treatment with Crystacide (10 days) improves the microcirculation and decreases skin free radicals improving healing.