Comparing Zytenz vs. Extenze, both have problems. The U.S. FDA has banned Extenze. The FDA claims Extenze can kill you because Extenze contains illegal drugs that create dangerous high blood pressure. Zytenz has never been banned by the FDA. Meanwhile, the Mayo Clinic claims supplements like Zytenz can be dangerous for your Blood Pressure during sex. Many Zytenz Reviews claim Zytenz is just an average working pill with a common formula seen in many pills. Zytenz is the lesser of two evils.