Fig. 4.

Changes in the ED degree category (a) and vasculogenic ED degree category (b), from baseline (T0—black series) to 90 days after l-arginine supplementation (T1—green series), for each patient in l-arginine group, and changes in the ED degree category (c) and vasculogenic ED degree category (d), from baseline (T0—black series) to 90 days (T1—blue series), for each patient in placebo group; the area outside the black circle marks the no ED (IIEF-6 score within the range 26–30 points) category (a, c) and the no vasculogenic ED (PSV > 35 cm/s) category (b, d), comprising 12 and 10 patients in l-arginine group, respectively, and 1 and 4 patients in placebo group, respectively, at study completion