The therapeutical effect of dipyridamole (Dp) on chronic glomerulonephritis and nephrotic syndrome in large administration (300 mg/day and 450 mg/day for 4 weeks) was investigated in a double blind group comparison method This study was started with 34 patients at first, but 6 patients dropped out afterwards. Therefore, 28 patients were finally subjected to our analysis. Among them, 8 were patients with chronic glomerulonephritis (urinary protein : over 2 g/day) and 20 patients with nephrotic syndrome (primary : 15 patients, diabetic : 5) On the average, the decrease rate of urinary protein (D) was 48% in all 28 cases, 41% in 300 mg/day administration group (Group I, 13 cases) and 48% in 450 mg/day administration group (Group II, 15 cases). Average D was also observed 40% in 21 cases who were administered Dp alone (50% in 10 cases of Group I, 30% in 11 cases of Group II ), 78% in 6 cases who were administered a steroidal agent concomitantly (36% in 2 cases of Group I, 99% in 4 cases of Gouup II), and 0.8% in 1 case who was administered a steriodal agent and an immunosuppressive agent concomitantly. The urinaryprotein-decreasing effect of Dp was categorized into "remarkable improvement" (A) in case of D 50/, "slight improvement" (B) in case of 25% < D < 50% and "effective" for A+B, It was found ont that 15 cases fell under A and 4 cases under B in all 28 cases (effective rate : 68%) By groups, 6 cases fell under A and 3 cases under B in Group I (effective rate : 69%), and 9 cases fell under A and 1 case under B in Group II (effective rate : 67%). In other examinations, serum albumin and total cholesterol improved and plasma fibrinogen tended to improve. As a result of histological investigations, effective rates of Dp were obsereved to be high on prolif rateive glomerulonephritis and diabetic nephropathy. Thus, significant difference was not observed in therapeutical effect of Dp on chronic glomerulo nephritis and nephrotic syndrome between administration by 300 mg/day and 450 mg day, so that the 300 mg day administration of Dp seems sufficient for the treatment of renal disease. In case any effect is not produced by the 300 mg/day administration, dose should be increased. Also a great hope can be laid on the effect of the concomitant use of Dp with steroidal agents on steroid-resistant nephrotic syndrome.
