L-Arginine is a potent nitric oxide enhancer and causes vasodilation of both smooth and skeletal muscles. It is often used in cases of colic to help reduce spasms and ischemia of the vascular areas of the intestine. It also works well to dilate the skeletal muscle vessels, thus providing more blood flow. Arginine works well in “ty-up” horses. Vasodilatory properties are also extremely useful when treating bleeders because they reduce resistance to blood flow through the lungs.