ED. Pd5 inhibitors are the mainstay of therapy for ED. Sildenafil, vardenafil, and tadalafil are the only ones FDA approved in the US. Urethral suppositories of prostaglandine1 as well as injectable pge1 are available and FDA approved. Other injections of papaverine, regitine (phentolamine) and Atropine are used but not FDA approved for ED. Stay away from the so called natural alternatives; a waste of $$$$.
Viagra, (sildenafil) Cialis and. Levitra (vardenafil).