L-arginine: L-arginine is an amino acid present in the proteins of all life forms. Also, referred to as arginine, this amino acid is required to carry out the synthesis of nitric oxide, which relaxes the blood vessels and allows more blood to flow through arteries (13). L-arginine has shown promise in the treatment and prevention of cardiovascular disease and in the treatment of male infertility (13). With its anti-oxidant properties, L-arginine can be an integral part of any sexual wellness supplement.
Reiter, W. J., Pycha, A., Schatzl, G., Pokorny, A., Gruber, D. M., Huber, J. C., & Marberger, M. (1999, March). Dehydroepiandrostone in the treatment of erectile dysfunction: A prospective, double-blind, randomized, placebo-controlled study [Abstract]. Urology, 53(3), 590-594. Retrieved from http://www.sciencedirect.com/science/article/pii/S0090429598005718

Yohimbe A number of clinical trials have shown that the primary component of this bark from an African tree can improve sexual dysfunction associated with selective-serotonin reuptake inhibitors (SSRIs) used to treat depression. This herb has been linked to a number of side effects, including increased blood pressure, fast or irregular heartbeat, and anxiety. Yohimbe shouldn't be used without a doctor's supervision.