Ashwagandha’s reputation as a sexual enhancement herb is supported by research. One animal study showed that extracts of ashwagandha increased production of sex hormones and sperm, presumably by exerting a testosterone-like effect. In another clinical trial, the herb (taken at a dose of 3 gm per day for 1 year) was given to healthy male adults 50–59 years of age. Among benefits noted: serum cholesterol levels decreased, gray hair was reduced, and a vast majority (over 70%) reported improvement in sexual performance.
Animal testicles: derived from bulls and wild boars, the orchic substance has been used as a way to possibly increase testosterone levels and sperm counts. In Singapore, testis soap was once very popular (Figure 2). It is still sold in parts of China and Japan. The dried Dog testis and penis (canis familiaris) is believed to tonify the kidneys and strengthen the yang II. Kidney deficiency is believed to be the cause of impotency in Chinese literature.
Red Ginseng — One small randomized trial found evidence that red ginseng may offer modest improvements in ED symptoms (as compared with placebo). A meta-anaylsis published in the British Journal of Clinical Pharmacology states, “Traditionally red ginseng has been used to restore and enhance normal well-being, and is often referred to as an adaptogenic….Possible mechanisms of action of red ginseng include hormonal effects similar to those of testosterone. Others have postulated that red ginseng might induce relaxation of the smooth muscles.”  (5)
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.