Suggested intake: “The problem with yohimbine is that you can’t regulate the amount in a dosage,” says Fratellone. “It all depends on what part of the tree it comes from, how it’s cultivated, how it’s exported, and so on. The amount of extract you get will vary.” FDA researchers analyzed a number of over-the-counter yohimbe bark products. They found that the supplements contained only seven percent or less of the amount of yohimbine that would be found in actual yohimbe bark, which suggests that they contained little or no yohimbe. However, the prescription form of yohimbine is strictly regulated by the FDA. It is approved only for the treatment of impotence, and is available in tablets and capsules. For erectile dysfunction, 5.4 to 10 milligrams three times daily has been studied and regarded as generally safe.
Yohimbe has been found to increase circulation to the erectile tissues; aiding in the resolution of physiological and psychogenic (mental/emotional) impotence. Impotence, the inability to sustain erection, is the most common sexual disorder among men. Yohimbine is the active component found in yohimbe bark. Yohimbine has been shown to dilate the blood vessels and lower blood pressure, which enlarges the vessels in the sexual organs and increases reflex excitability in the lower spinal cord. In many cases, yohimbe has shown to make erections firmer. It is thought to help sustain an erection by causing compression and preventing blood to flow back out of the penis while sexually aroused.
Relevant publications were searched up to November 2010 in the MEDLINE (PubMed) database. The citation lists of randomized controlled trials on the effect of aerobic training and Erectile Dysfunction management using the International Index of Erectile Function (IIEF) as treatment outcome measure. Studies on different operative techniques on the effects of aerobic training for men with Erectile Dysfunction due to arterogenic Erecile Dysfunction were selected. Data on participants' characteristics, study quality, population, intervention, treatment outcome were collected and analyzed.
Reduction of the libido index was the major disadvantage that we observed with zinc supplementation. Substances that affect libido usually act centrally and may reduce desire by causing sedation or hormonal disturbances. The role of elevated levels of PRL in serum as an inhibitor of sexual drive and gonadal function is well established. This reduction of sex drive may occur through the modification of activity of dopaminergic neurons in the CNS that are regarded as controlling sexual motivation and function. Our study demonstrated a significant increase of serum PRL level (2.9 to 7.22 ng/dl) within two weeks of supplementation of zinc (5 mg/day). This is a possible explanation for the reduced libido with increasing doses of zinc observed in this study.
Men typically have higher zinc needs than women, which can make them more vulnerable to zinc deficiencies. In men, zinc is also needed to support healthy prostate and penile function. Keep in mind that excessive amounts of zinc can be harmful so it is best to follow package directions on the supplement you choose, should you decide to supplement with the mineral.
The human body only contains 2 or 3 grams of zinc at any given time. Zinc is distributed throughout the body in organs, blood, and bones. It can be difficult to diagnose zinc deficiency. While a low blood zinc level does indicate a deficiency, a normal blood level does not necessarily indicate the absence of a deficiency. And examination of the hair for zinc or a zinc taste test (ZTT) may also be used for supportive evidence in the diagnosis of zinc deficiency.