title: Changes in ED therapy in the Viagra era.
authors: Massachusetts General Hospital, Boston 02114, USA.
authors: R J
authors: RJ
authors: Krane
mesh_terms: D007172:Erectile Dysfunction / Q000188:drug therapy*; D006801:Humans; D008297:Male; D010726:Phosphodiesterase Inhibitors / Q000627:therapeutic use*; D010879:Piperazines / Q000627:therapeutic use*; D011687:Purines; D000068677:Sildenafil Citrate; D013450:Sulfones
chemical_list: D010726:Phosphodiesterase Inhibitors; D010879:Piperazines; D011687:Purines; D013450:Sulfones; D000068677:Sildenafil Citrate