RT Journal Article SR Electronic T1 Sildenafil (Viagra) for treating male erectile dysfunction JF Cleveland Clinic Journal of Medicine JO Cleve Clin J Med FD Cleveland Clinic SP 301 OP 304 VO 65 IS 6 A2 Vidt, Donald G. A1 Licht, Mark R. YR 1998 UL http://www.ccjm.org/content/65/6/301.abstract AB Sildenafil, the first oral drug for treating male erectile dysfunction, appears effective and well tolerated. However, more time and experience will be needed to establish this drug’s true efficacy and safety.