Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Improvement of erectile function with Prelox: a randomized, double-blind, placebo-controlled, crossover trial

Abstract

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.

This is a preview of subscription content, access via your institution

Access options

Rent or buy this article

Prices vary by article type

from$1.95

to$39.95

Prices may be subject to local taxes which are calculated during checkout

Figure 1
Figure 2

References

  1. Simonsen U, García Sacristán A, Prieto D . Penile arteries and erection. J Vasc Res 2002; 39: 283–303.

    Article  CAS  Google Scholar 

  2. Chen J, Wollman Y, Chermichovsky T, Iaina A, Sofer M, Matzkin H . Effect of oral administration of high-dose nitric oxide donor L-arginine in men with organic erectile dysfunction: results of a double-blind, randomized, placebo-controlled study. BJU Int 1999; 83: 269–273.

    Article  CAS  Google Scholar 

  3. Klotz T, Mathers MJ, Braun M, Bloch W, Engelmann U . Effectiveness of oral L-arginine in first-line treatment of erectile dysfunction in a controlled crossover study. Urol Int 1999; 63: 220–223.

    Article  CAS  Google Scholar 

  4. Lebret T, Herve JM, Gorny P, Worcel M, Botto H . Efficacy and safety of a novel combination of L-arginine glutamate and yohimbine hydrochloride: a new oral therapy for erectile dysfunction. Eur Urol 2002; 41: 608–613.

    Article  CAS  Google Scholar 

  5. Fitzpatrick DF, Bing B, Rohdewald P . Endothelium-dependent vascular effects of Pycnogenol. Cardiovasc Pharmacol 1998; 32: 509–515.

    Article  CAS  Google Scholar 

  6. Durackova Z, Trebaticky B, Novotny V, Zitnanova A, Breza J . Lipid metabolism and erectile function improvement by Pycnogenol®, extract from the bark of Pinus pinaster in patients suffering from erectile dysfunction—apilot study. J Nutr Res 2003; 23: 1189–1198.

    Article  CAS  Google Scholar 

  7. Rohdewald P . Pycnogenol, French maritime pine bark extract. In: Encyclopedia of Dietary Supplements. Marcel Dekker: New York, 2005, pp 545–553.

    Google Scholar 

  8. USP monograph: maritime pine bark extract. The United States Pharmacopoeia, United States Pharmacopoeial Convention, US Pharmacopoeia 28, 2024–2025.

  9. Stanislavov R, Nikolova V . Treatment of erectile dysfunction with Pycnogenol® and L-arginine. J Sex Marital Ther 2003; 29: 207–213.

    Article  CAS  Google Scholar 

  10. Lamm S, Schönlau F, Rohdewald P . Prelox for improvement of erectile function: a review. Eur Bull Drug Res 2003; 11: 29–37.

    Google Scholar 

  11. Rosen RC, Riley A, Wagner G, Osterloh IH, Kirkpatrick J, Mishra A . The international index of erectile function (IIEF): a multidimensional scale for assessment of erectile dysfunction. Urology 1997; 49: 822–830.

    Article  CAS  Google Scholar 

  12. Stanislavov R, Nikolova V . Prelox® plus testosterone for achieve fertilization in previously infertile men. Eur Bull Drug Res 2005; 13: 7–13.

    Google Scholar 

  13. Raijfer J, Aronson W, Bush P, Dorey F, Ignarro L . Nitric oxide as a mediator of relaxation of the corpus cavernosum in response to noradrenergic noncholinergic neurotransmission. N Engl J Med 1992; 326: 90–94.

    Article  Google Scholar 

  14. Cappelleri JC, Rosen RC, Smith MD, Mishra A, Osterloh IH . Diagnostic evaluation of the erectile function domain of the international index of erectile function. Urology 1999; 54: 346–351.

    Article  CAS  Google Scholar 

  15. Garban H, Vernet D, Freedman A, Raijfer J, Conzales-Cadavid N . Effect of aging on nitric oxide-mediated penile erection in rats. Am J Physiol 1995; 268: H467–H475.

    CAS  PubMed  Google Scholar 

  16. Carrier S, Nagaraju P, Morgan DM, Baba K, Nunes L, Lue TF . Age decreases nitric oxide synthase-containig nerve fibers in the rat penis. J Urol 1997; 157: 1088–1092.

    Article  CAS  Google Scholar 

  17. Smith AR, Visioli F, Frei B, Hagen TM . Age-related changes in endothelial nitric oxide synthase phosphorylation and nitric oxide dependent vasodilation: evidence for a novel mechanism involving sphingomyelinase and ceramide-activated phosphatase 2A. Aging Cell 2006; 5: 391–400.

    Article  CAS  Google Scholar 

  18. Wei ZH, Peng QL, Lau BHS . Pycnogenol® enhances endothelial cell antioxidant defenses. Redox Rep 1997; 3: 219–224.

    Article  CAS  Google Scholar 

  19. Zini A, O'Bryan MK, Magid MS, Schlegel PN . Immunohistochemical localization of endothelial nitric oxide synthase in human testis, epididymis, and vas deferens suggests a possible role for nitric oxide in spermatogenesis, Sperm maturation, and programmed cell death. Biol Reprod 1996; 55: 935–941.

    Article  CAS  Google Scholar 

  20. Soléru SG, Ennaji A, Cournot A, Spira A . LH pulsatile secretion and testosterone blood levels are influenced by sexual arousal in human males. Psychoneuroendocrinology 1993; 280: 205–218.

    Article  Google Scholar 

  21. Soléru S, Gregoire MC, Gerard D, Decety J, Lafarge E, Cinotti L et al. Neuroanatomical correlates of visually evoked sexual arousal in human males. Arch Sex Behav 1999; 28: 1–21.

    Article  Google Scholar 

  22. Heilhammer DH, Hubert W, Schürmeyer T . Changes in saliva testosterone after psychological stimulation in men. Psychoneuroendocrinology 1985; 10: 77–81.

    Article  Google Scholar 

  23. Schweiger U, Deuschle M, Weber B, Korner A, Lammer CH, Schmider J et al. Testosterone gonadotropin and cortisol secretion in male patients with major depression. Psychosomat Med 1999; 61: 292–296.

    Article  CAS  Google Scholar 

  24. Unden F, Ljunggren JG, Beck-Friis J, Kjellman BF, Wetterberg L . Hypothalamic-pituitary-gonadal axis in major depressive disorders. Acta Psychiatr Scand 1988; 78: 138–164.

    Article  CAS  Google Scholar 

  25. Hosseini S, Lee J, Sepulveda RT, Fagan T, Rohdewald P, Watson RR . A randomized, double blind, placebo controlled, prospective, 16 week crossover study to determine the role of Pycnogenol® in modifying blood pressure in mildly hypertensive patients. Nutr Res 2001; 21: 67–76.

    Article  Google Scholar 

  26. Liu X, Wei J, Tan F, Zhou S, Würthwein G, Rohdewald P . Pycnogenol®, French maritime pine bark extract, improves endothelial function of hypertensive patients. Life Sci 2004; 74: 855–862.

    Article  CAS  Google Scholar 

  27. Devaraj S, Vega-López S, Kaul N, Schönlau F, Rohdewald P, Jialal I . Supplementation with a pine bark extract rich in polyphenols increases plasma antioxidant capacity and alters the plasma lipoprotein profile. Lipids 2002; 37: 931–934.

    Article  CAS  Google Scholar 

  28. Koch R . Comparative study of Venostasin® and Pycnogenol® for treatment in chronic venous insufficiency. Phytother Res 2002; 16: 1–5.

    Article  Google Scholar 

Download references

Acknowledgements

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.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to P Rohdewald.

Additional information

Competing Interests

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.

Rights and permissions

Reprints and permissions

About this article

Cite this article

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

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/sj.ijir.3901597

Keywords

This article is cited by

Search

Quick links