erectile dysfunction
"Am 45 on blood pressure medicines. Have tried samples of all three erectile dysfunction medicines.  Viagra and Levitra both give me headaches.  Cialis, however, gives me no side effects whatsoever, except of course for a great erection (even if I've been drinking).  And it lasts for the 36 hours as advertised.  Nice to be able to take one on Friday night and be good for the whole weekend."