title: Dose-response analysis of effects of tibolone on climacteric symptoms.
abstract: OBJECTIVE
  To assess the clinically optimal tibolone dose for the relief of climacteric complaints.
  
  
  METHODS
  A randomised, double blind, placebo-controlled trial.
  
  
  METHODS
  Twenty-eight centres in Norway, The Netherlands, Sweden and Finland.
  
  
  METHODS
  Seven hundred and seventy-five healthy postmenopausal women were randomised to tibolone in a daily dose of 0.625, 1.25, 2.5 or 5.0 mg or placebo for 12 weeks.
  
  
  METHODS
  At baseline, and after 4, 8 and 12 weeks, hot flushes, sweating, vaginal bleeding and adverse experiences were recorded.
  
  
  METHODS
  Change in frequency and intensity of hot flushes and sweating over 12 weeks.
  
  
  RESULTS
  From week four onwards, 2.5 and 5.0 mg tibolone were significantly more effective than placebo, regarding the frequency of hot flushes and sweating (P < 0.001), whereas the 0.625 mg dose was not significantly different from placebo during the study. The frequency of hot flushes with the 1.25 mg dose was statistically significantly different from placebo, only from week eight onwards. The incidence of dropouts due to insufficient therapeutic effect was much higher in the tibolone 1.25 mg group (9.5%) than in the 2.5 (1.9%) and 5.0 mg (1.3%) groups. A dose-related increase in incidence of vaginal bleeding or spotting was observed (P < 0.0001). Bleeding incidence in the 5.0 mg dose group was about twice as high as in the 2.5 mg dose group. There was no difference in incidence of adverse experiences between the 2.5- and the 1.25 mg dose group.
  
  
  CONCLUSIONS
  A daily dose of 2.5 mg tibolone is the clinically optimal dose for the treatment of climacteric complaints in postmenopausal women.
authors.affiliation: Karolinska Hospital, Stockholm, Sweden.
authors.forename: M B
authors.initials: MB
authors.lastname: Landgren
authors.forename: H J T Coelingh
authors.initials: HJ
authors.lastname: Bennink
authors.forename: F A
authors.initials: FA
authors.lastname: Helmond
authors.forename: S
authors.initials: S
authors.lastname: Engelen
mesh_terms: D000328:Adult; D002979:Climacteric / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D020847:Estrogen Receptor Modulators / Q000008:administration & dosage*; D005260:Female; D019584:Hot Flashes / Q000188:drug therapy; D006801:Humans; D008875:Middle Aged; D009652:Norpregnenes / Q000008:administration & dosage*; D013546:Sweating / Q000187:drug effects; D014592:Uterine Hemorrhage / Q000139:chemically induced
chemical_list: D020847:Estrogen Receptor Modulators; D009652:Norpregnenes; C027385:tibolone