Priapism, which many may know better as an erection that lasts longer than four hours, has responded well to a new treatment tested by researchers at The University of Texas Medical School at Houston. At this point, men who develop priapism have few treatment choices for this painful condition.
Men are warned about the possibility of priapism every time they hear a commercial for prescription medication taken to treat erectile dysfunction (ED), yet the term for this rare side effect of ED drugs is seldom used. Priapism develops when blood in the penis becomes trapped and cannot drain out. The condition can occur in males of any age, including newborns, but it is most common between the ages of 5 and 10 years and 20 to 50 years. It is highly associated with leukemia, sickle cell disease, and other blood disorders.
If priapism is not treated immediately, it can result in penile fibrosis, a condition that involves scarring and permanent erectile dysfunction. Thus the announcement that a new treatment could offer a solution can be encouraging for the thousands of men who are afflicted by this condition. The new treatment is actually a novel use for an FDA-approved (Food and Drug Administration) drug called polyethylene glycol-linked adenosine deaminase (PEG-ADA), which is used to treat people who have a deficiency of adenosine deaminase enzyme (ADA). People who are ADA deficient have a condition called Severe Combined Immunodeficiency Disease.
Researchers at The University of Texas propose that priapism is associated with elevated levels of adenosine, a finding they made during previous research in ADA-deficient mice that had long-lasting spontaneous erections. In that study they showed they could prevent and treat priapism in mice. In this latest study, the investigators used PEG-ADA in a group of mice with sickle cell disease features and another group with ADA enzyme deficiency and showed they could prevent penile fibrosis.
Men who have sickle cell disease have a 40 percent chance of developing priapism. The current treatment options for priapism include pain control medication, hydration, and surgery. None of these choices are especially effective. Introduction of a medication that would prevent or treat this condition would be most welcome.
University of Texas Health Science Center at Houston, news release Oct. 29, 2009