Tadalafil
"I am soon to be 79 and unable to get an erection for over 4 years.  I have had Parkinson't disease for 16 years and on several meds.  My wife was wonderful in helping me find the best time to take Cialis, starting with 10mg dose.  Helped some but had to go to 20mg dose.  Over the top results in about 4-5 hours.  Lasted over an hour and was able to ejaculate normally! My wife is 67 and an eager partner which makes all the difference in the world!  I am alive again!"