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
The causes of ED are varies from one individual to another. For whatever cause, since an erection requires a precise sequence of events, ED can occur when any of the events is disrupted. This sequence includes nerve impulses in the brain, spinal column, and area around the penis, and response in muscles, fibrous tissues, veins, and arteries in and near the corpora cavernosa23. Thus, ED causes reported include, damage to nerves, arteries, smooth muscles, and fibrous tissues. These are often as a result of diseases, such as diabetes, kidney disease, chronic alcoholism, multiple sclerosis, atherosclerosis, vascular disease, and neurologic diseases that account for about 70 percent of ED cases23. NIH23 reported that between 35 and 50 percent of men with diabetes experience ED. NIH23 further reported that the usage of many common medicines such as blood pressure drugs, antihistamines, antidepressants, tranquilizers, appetite suppressants, and cimetidine (an ulcer drug) can produce ED as a side effect. Nevertheless, psychological factors such as stress, anxiety, guilt, depression, low self-esteem, and fear of sexual failure cause 10 to 20 percent of ED cases. In addition, men with a physical cause for ED frequently experience the same sort of psychological reactions (stress, anxiety, guilt, depression)23. Other possible causes are smoking, which affects blood flow in veins and arteries, and hormonal abnormalities, such as not enough testosterone23.
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.