title: Dose-dependent efficacy of the Vitex agnus castus extract Ze 440 in patients suffering from premenstrual syndrome.
abstract: BACKGROUND
  Preparations of Vitex agnus castus L. (VAC) have been shown to be effective to treat irregular menstrual cycles, cyclical mastalgia and symptoms of the premenstrual syndrome (PMS). However, the dose-effect relationship for the treatment of PMS has not yet been established. This study aimed to investigate the clinical effects of three different doses of the VAC extract Ze 440 in comparison to placebo in patients suffering from PMS.
  
  
  METHODS
  In a multicenter, double-blind, placebo-controlled, parallel-group study, 162 female patients with PMS (18-45 years) were randomized to either placebo or different doses of Ze 440 (8, 20 and 30 mg) over three menstrual cycles. PMS symptoms' severity was assessed by patients using visual analog scales (VAS) for the symptoms irritability, mood alteration, anger, headache, bloating and breast fullness.
  
  
  RESULTS
  Each of the treatments was well tolerated. Improvement in the total symptom score (TSS) in the 20mg group was significantly higher than in the placebo and 8 mg treatment group. The higher dose of 30 mg, on the other hand, did not significantly decrease symptom severity compared to the 20mg treatment, providing a rational for the usage of 20mg. Corresponding results were observed with the single PMS symptom scores.
  
  
  CONCLUSIONS
  This study demonstrated that the VAC extract Ze 440 was effective in relieving symptoms of PMS, when applied in a dose of 20mg. Therefore, for patients suffering from PMS, 20mg Ze 440 should be the preferred daily dose.
authors.affiliation: Institute for Health Care and Science, Hüttenberg, Germany.
authors.forename: Ruediger
authors.initials: R
authors.lastname: Schellenberg
authors.forename: Christian
authors.initials: C
authors.lastname: Zimmermann
authors.forename: Jürgen
authors.initials: J
authors.lastname: Drewe
authors.forename: Godehard
authors.initials: G
authors.lastname: Hoexter
authors.forename: Catherine
authors.initials: C
authors.lastname: Zahner
mesh_terms: D000328:Adult; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004365:Drugs, Chinese Herbal / Q000008:administration & dosage* / Q000494:pharmacology / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008517:Phytotherapy; D011293:Premenstrual Syndrome / Q000150:complications / Q000188:drug therapy*; D012720:Severity of Illness Index; D020950:Vitex; D055815:Young Adult
chemical_list: D004365:Drugs, Chinese Herbal; C553090:Vitex agnus castus extract