Long-term high-dose l-arginine supplementation in patients with vasculogenic erectile dysfunction: a multicentre, double-blind, randomized, placebo-controlled clinical trial

Abstract

Purpose The current randomized, double-blind, placebo-controlled clinical trial addressed the effects on penile erectile function of relatively high daily oral doses (6 g/day) of l-ARG for 3 months (N = 51) compared to placebo (N = 47), in patients with vasculogenic ED, with comparison between mild–moderate and severe vasculogenic ED. Methods The outcome measures included IIEF-6 score and cavernous arteries peak systolic flow velocity (PSV) at dynamic penile duplex ultrasonography (PDU). Results l-ARG supplementation for 3 months significantly increased IIEF-6 score in the overall cohort (p < 0.0001) and in subgroups of patients with mild–moderate (p < 0.0001) and severe (p = 0.007) vasculogenic ED; PSV was significantly increased in the overall cohort (p < 0.0001) and in patients with mild–moderate (p < 0.0001), but not severe vasculogenic ED. At study completion, 74% of patients improved ED degree category, although only 24% of patients, mainly belonging to the baseline category of mild ED, reached IIEF-6 scores compatible with absence of ED; moreover, 20% of patients, exclusively belonging to the baseline category of mild–moderate vasculogenic ED, reached PSV values compatible with absence of ED. Conclusion The results of the current study demonstrated that supplementation with relatively high doses of l-ARG as a single compound for 3 months significantly improved penile erectile function, assessed by both IIEF-6 score and PSV at dynamic PDU in patients with mild–moderate, and improved IIEF-6 score, but not PSV, in patients with severe vasculogenic ED, therefore suggesting that l-ARG might be an alternative treatment in mild–moderate vasculogenic ED patients experiencing adverse effects or with contraindications for chronic treatment with PDE5i compounds.

The management of erectile dysfunction in men with diabetes mellitus unresponsive to phosphodiesterase type 5 inhibitors

“…Some evidence suggests that empiric therapies may have a role in diabetic patients non-responding to PDE5i without causing any serious adverse effects. [67][68][69][70] For example, L-arginine is a NO precursor which is therefore necessary for smooth muscle relaxation in the cavernous corpora. 71 Likewise, nicotinic acid is related to energy production in the endothelium and is a vasodilator and thus may improve erectile function.…”

“…Some evidence suggests that empiric therapies may have a role in diabetic patients non‐responding to PDE5i without causing any serious adverse effects 67–70 . For example, l ‐arginine is a NO precursor which is therefore necessary for smooth muscle relaxation in the cavernous corpora 71 .…”

Effect of l-arginine compared to placebo on sexual function in women with major depressive disorder: a randomized controlled trial

“…The study compared the outcomes of mild- moderate and severe vasculogenic erectile dysfunction. The results of the study showed no serious complications reported in patients who received L-arginine [ 46 ]. In our study, the patients reported no dangerous side effects or injuries.…”