An Initial Evaluation of the Safety, Efficacy and Purity of VigRX, an Herbal Combination Formula, for the Enhancement of Male Sexual Health~!2009-12-10~!2010-03-04~!2010-03-31~!

Abstract

An herbal combination formula, known as VigRX, has been studied for purity, safety and for efficacy in a Sprague-Dawley rat model. Two separate assays determined that VigRX was free from pharmaceutical adulterants, including phosphodiesterase type 5 (PDE-5) inhibitors and related analogues. An in vitro assay determined that VigRX is able to inhibit the enzyme Rho-kinase, suggesting a potential mechanism of action for this product. A 2-week (14-day) study in rats demonstrated a marked enhancement in sexual behavior, including decreased intromission and ejaculation latencies, and increased intromission, ejaculation and mounting frequencies, upon oral administration of 30 mg/kg/day. A longer 12-week study using 15 mg/kg/day showed only a decrease in ejaculation latency with respect to sexual behavior. In both studies, the treatment led to increased intracavernosal pressure, increased sperm concentration, and increased width of erect penis (and an increase in erect penile length in the 14-day study only). There was a statistically significant increase in blood testosterone levels in rats at the end of the 12-week study, which did not occur in the 14-day study. A non-dose dependent decrease in kidney and liver weights was found in the 14-day study that was not seen in the 12-week study, and neither study found any notable histopathological changes in any tissues studied. In conclusion, these preliminary results demonstrate safety and efficacy of VigRx for use in supporting male erectile function, and justify further investigation in these areas.

Erectogenic and Aphrodisiac Effects ofButea frondosaKoenig ex Roxb. in Rats: Involvement of Enzyme Inhibition

“…In the present study, any observed increase in sperm parameters could also be attributed to cAMP and cGMP specific PDE inhibition. Another hypothesis for increase in sperm count by MEBF and sildenafil treatment is that these pharmacological agents increase blood flow to testes and consequently increase spermatogenesis [40]. …”

Evaluation of a multi-herb supplement for erectile dysfunction: a randomized double-blind, placebo-controlled study

“…Development of this product was based on the preliminary evaluation of a first generation product, VigRX, consisting of a proprietary blend of Panax ginseng Serenoa repens Gingko biloba Crataegus laevigata Ptychopetalum olacoides Erythroxylum catuaba Cuscuta chinensis , and Epimedium sagittatum extract. In two different studies in male Sprague–Dawley rats, VigRX was shown to engender a marked improvement in sexual behaviour including decreased intromission and ejaculation latencies, and increased intromission, ejaculation and mounting frequencies [ 11 ]. In the same study, assays for pharmaceutical adulteration found that VigRX did not contain any detectable levels of known PDE-5 inhibitors including sildenafil, tadalafil, vardenafil or related analogues.…”