Priapism is a prolonged and painful erection of the penis that is not associated with sexual stimulation, and can last from hours to several days. It occurs when the penis begins to fill with blood, as in a normal erection, but blood does not drain properly. It may be a result of illness or traumatic spinal cord injury or nerve centers of leukemia or inflammation of the urethra. But causes such as abuse of alcohol and other drugs (especially cocaine), consumption of antidepressants or to control blood pressure, or treatments for erectile dysfunction are also given. It is a problem that must be treated promptly by a medical professional, which drain blood from the penis with a needle and / or supply drugs