title: Electrocardiographic effects of an Ephedra-Free, multicomponent weight-loss supplement in healthy volunteers.
abstract: OBJECTIVE
  Metabolife 356, an ephedra-containing weight-loss product, substantially increases the corrected QT (QTc) interval. Metabolife Ephedra Free, a similar supplement, contains caffeine and extracts of green tea, garcinia cambogia, and yerba mate. Its electrocardiographic (ECG) effects are not known. Therefore, we sought to determine the effect of this supplement on the QTc interval.
  
  
  METHODS
  Randomized, double-blind, placebo-controlled, crossover study.
  
  
  METHODS
  University of Connecticut, Storrs Campus.
  
  
  METHODS
  Twenty healthy volunteers. Intervention. A single capsule containing half the normal recommended dose of Metabolife Ephedra Free or matching placebo was administered in crossover fashion, with a 7-day washout period between treatments.
  
  
  RESULTS
  Baseline and three postdose ECG measurements were obtained, and QTc intervals were measured over a 5-hour study period. No significant differences in the QTc interval or other ECG variables were observed between the Metabolife Ephedra Free and placebo groups.
  
  
  CONCLUSIONS
  At half the recommended single dose, Metabolife Ephedra Free does not affect the QTc interval or other ECG variables over 5 hours. Dose-response studies and studies of longer duration should be conducted.
authors.affiliation: School of Pharmacy, University of Connecticut, Storrs, 06102, USA.
authors.forename: Bokyung
authors.initials: B
authors.lastname: Min
authors.forename: Brian F
authors.initials: BF
authors.lastname: McBride
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Kardas
authors.forename: Agron
authors.initials: A
authors.lastname: Ismali
authors.forename: Vinnita
authors.initials: V
authors.lastname: Sinha
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Kluger
authors.forename: C Michael
authors.initials: CM
authors.lastname: White
mesh_terms: D000328:Adult; D019440:Anti-Obesity Agents / Q000008:administration & dosage / Q000009:adverse effects*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004562:Electrocardiography; D029789:Ephedra; D005260:Female; D006801:Humans; D008297:Male; D008517:Phytotherapy; D028321:Plant Preparations / Q000008:administration & dosage / Q000009:adverse effects
chemical_list: D019440:Anti-Obesity Agents; D028321:Plant Preparations