Possible side effects of Pro-Arginine usage include abdominal pain and bloating, diarrhea and gout, according to WebMD. It may also cause a worsening of breathing in people with asthma.
Pro-Arginine may interact with certain medications that lower blood pressure, explains WebMD. It may also interact with certain heart medications and drugs such as Viagra that treat erectile dysfunction. Pregnant women or women who are nursing should not start taking supplements without first consulting their doctor. Doses of Pro-Arginine that are too high can cause serious side effects including death in children. Pro-Arginine is possibly safe for most people when taken appropriately by mouth, administered as a shot or applied to the skin short-term.