Shindel, A. W., Xin, Z.-C., Lin, G., Fandel, T. M., Huang, Y.-C., Banie, L., … Lue, T. F. (2010, February 5). Erectogenic and neurotrophic effects of icariin, a purified extract of horny goat weed (Epimedium spp.) in vitro and in vivo. The Journal of Sexual Medicine, 7(4), 1518-1528. Retrieved from http://onlinelibrary.wiley.com/doi/10.1111/j.1743-6109.2009.01699.x/full
ED can be caused by a handful of things, but one thing’s for sure: You need a healthy supply of the neurotransmitter nitric oxide (NO) to get and maintain an erection. NO is produced in nerve tissue and helps jolt your Johnson by relaxing the smooth muscle so blood can fill the penis. After the initial release of NO, your body releases a cascade of chemicals—including more of the neurotransmitter—to help keep you hard and happy, according to a study in the Proceedings of the National Academy of Sciences.
If you have symptoms of ED, it’s important to check with your doctor before trying any treatments on your own. This is because ED can be a sign of other health problems. For instance, heart disease or high cholesterol could cause ED symptoms. With a diagnosis, your doctor could recommend a number of steps that would likely improve both your heart health and your ED. These steps include lowering your cholesterol, reducing your weight, or taking medications to unclog your blood vessels.