The variation of capillary filtration rate (CFR), ankle circumference (AC), and ankle edema (AE) was evaluated in three groups of patients with venous hypertension (ambulatory venous pressure >42 mm Hg) and in a group of normal subjects before and after treatment for 4 weeks with total triterpenic fraction of Centella asiatica (TTFCA), a venoactive drug acting on the microcirculation and on capillary permeability. Group A (20 patients)was treated with TTFCA 60 mg thrice daily, group B (20 patients) was treated with 30 mg thrice daily; group C (12 patients) was treated with placebo; and group D (10 normal subjects) was treated with TTFCA 60 mg thrice daily in a randomized study. Capillary filtration rate was assessed by venous occlusion plethysmography, ankle edema by a new system called AET (ankle edema tester). Subjective symptoms of venous hypertension were assessed by an analogue scale line considering four symptoms: swelling sensation, restless lower extremity, pain and cramps, and tiredness. CFR, AC, and AE were significantly higher in patients in comparison with normal subjects. After 4 weeks of TTFCA treatment, there was a significant decrease of CFR, AC, and AET time in patients. This was also greater in the higher dose group. No significant change was observed in the placebo group and in normal subjects treated with TTFCA. Symptoms were also significantly improved in the two groups treated with the active drug according to the dose. No significant changes were observed in the placebo group. In conclusion, the improvement of signs and symptoms by TTFCA observed in patients with venous hypertension was well correlated with the improvement of CFR and ankle edema. Dose ranging showed that 180 mg/day is more effective in improving symptoms and CFR.