Effects of VigRX™ on Sexual Behavior and Physiology

First Research Report (September 2005)

This initial preclinical study, submitted to AIBMR Life Sciences in September 2005 by investigators at a leading Thai university, examined the sexual health and physiological effects of VigRX in adult male Sprague-Dawley rats over a 14-day oral dosing period. It served as a critical early proof-of-concept, generating the data that informed subsequent larger and longer trials.

Study Design

Adult male Sprague-Dawley rats received VigRX orally at two doses — 15 mg/kg/day and 30 mg/kg/day — or distilled water (1 mL/day) as a control for 14 consecutive days. Researchers assessed sexual behavior (sex drive, mounting, intromission, ejaculation), erect penile size, intracavernous pressure (ICP), sperm density, blood testosterone, and the weights of key organs including the liver, kidney, penis, testes, epididymis, seminal vesicle, prostate, adrenal gland, spleen, and pituitary.

Key Findings — Sexual Health

At 30 mg/kg/day, VigRX significantly increased sex drive, erect penile size, intracavernous pressure, and sperm density in treated rats compared to controls. These improvements were statistically significant and meaningful in magnitude, demonstrating that VigRX's herbal formula has measurable, dose-dependent effects on the core physiological drivers of male sexual performance and health.

Key Findings — Testosterone and Organ Weights

Blood testosterone levels did not differ significantly between VigRX-treated and control groups in this 14-day study — consistent with the hypothesis that testosterone effects may require longer supplementation periods. Body weight and the weights of reproductive organs (penis, testes, epididymis, seminal vesicle, prostate, adrenal gland, spleen, pituitary) were not significantly different between groups. However, liver and kidney weight were modestly lower in the 30 mg/kg group compared to controls.

Safety Observations

No adverse behavioral signs were observed during the study period, and organ weight changes were not accompanied by any histopathological findings. The minor liver and kidney weight reduction was noted as an observation requiring further investigation, which was subsequently addressed and resolved in the follow-up 12-week study, where these differences did not recur.

Conclusion

This first report established the foundational efficacy signal for VigRX — demonstrating clear, dose-dependent improvements in sexual drive, penile erection quality, and sperm density at 30 mg/kg/day. No significant safety concerns were identified, making this an important early milestone in VigRX's clinical research program.

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