In a randomly allocated, double-blind, placebo-controlled, crossover design, 50 patients with mild to moderate erectile dysfunction (ED) were treated for 1 month with placebo or a combination of L-arginine aspartate and Pycnogenol (Prelox). Patients reported sexual function from diaries. Testosterone levels and endothelial NO synthase (e-NOS) were monitored along with routine clinical chemistry. Intake of Pycnogenol for 1 month restored erectile function to normal. Intercourse frequency doubled. e-NOS in spermatozoa and testosterone levels in blood increased significantly. Cholesterol levels and blood pressure were lowered. No unwanted effects were reported. Prelox is a promising alternative to treat mild to moderate ED.
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We thank Dr J Gerß from the Institute of Medical Informatics and Biomathematics of the University Clinics Münster, Germany, for statistical evaluation of data. This study was funded by Horphag Research Ltd, UK.
Dr Stanislavov received a grant from Horphag Research Ltd to perform this study. Dr Rohdewald is a consultant for Horphag Research Ltd and holds a patent for the method of increasing sexual wellness with a combination of proanthocyanidins and L-arginine.
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Stanislavov, R., Nikolova, V. & Rohdewald, P. Improvement of erectile function with Prelox: a randomized, double-blind, placebo-controlled, crossover trial. Int J Impot Res 20, 173–180 (2008). https://doi.org/10.1038/sj.ijir.3901597
- erectile dysfunction
- endothelial nitric oxide synthase (e-NOS)
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