Overview Study For Which Treatment, Tadalafil or Sildenafil, is Preferred For Problems Getting or Maintaining an Erection Status: Completed Trial end date: 2004-11-01 Target enrollment: Participant gender: Summary To determine if men prefer tadalafil or sildenafil for getting and keeping an erection after treatment with both drugs. Phase: Phase 4 Details Lead Sponsor: Eli Lilly and CompanyCollaborator: ICOS CorporationTreatments: Sildenafil CitrateTadalafil