Erectile Dysfunction ED is is a result of poor circulation and can be caused by drugs such as insulin. Diabetes contributes to poor circulation. Erection drugs that provide a temporary erection compound the problems of circulation. Finding ways to increase circulation and lower diabetes glucose levels, thus reducing diabetes drugs may restore circulation.

1. "Nitric oxide, known as the 'endothelium-derived relaxing factor', or 'EDRF', is biosynthesised from arginine and oxygen by various nitric oxide synthase (NOS) enzymes and by reduction of inorganic nitrate. The endothelium (inner lining) of blood vessels use nitric oxide to signal the surrounding smooth muscle to relax, thus dilating the artery and increasing blood flow. The production of nitric oxide is elevated in populations living at high-altitudes, which helps these people avoid hypoxia. Effects include blood vessel dilatation, neurotransmission (see Gasotransmitters), modulation of the hair cycle, and penile erections. Nitroglycerin and amyl nitrite serve as vasodilators because they are converted to nitric oxide in the body. Sildenafil, popularly known by the trade name Viagra, stimulates erections primarily by enhancing signaling through the nitric oxide pathway in the penis." http://en.wikipedia.org/wiki/Nitric_oxide

2. "NITRIC OXIDE by Ray Sahelian, M.D. "Does a Nitric Oxide Supplement Work? Nitric oxide is a molecule that plays a crucial role in vascular disease. Nitric oxide has a number of actions that lead to relaxation of blood vessels, regeneration of the endothelium (the inner lining of arteries), and inhibition of platelet clumping which makes the blood thinner. The role of nitric oxide in vascular disease has been investigated over the past two decades and scientists have discovered that this molecule is involved in many cardiovascular diseases, including atherosclerosis and thickening of the endothelium. In addition, nitric oxide has been used as a therapeutic tool to treat diseases that range from recurrent narrowing of arteries to inhibiting clotting events. Many commonly used medications have their therapeutic actions through the production of nitric oxide." http://www.raysahelian.com/nitricoxide.html

3. "CONCLUSION(S): Insulin resistance states are characterized by defective vascular NO production and impaired insulin-induced vasodilation, both of which are likely to cause ED. Diagnosing and treating insulin resistance should be part of the initial management plan for ED. Future studies concerning the cause and effect relationship of insulin resistance and ED should be implemented." PMID: 1749871