Objective: To determine the magnitude and determinants of weight loss in humans exposed to betahistine, a centrally acting histamine-1 (H-1) agonist and partial histamine-3 (H-3) antagonist.
Design: A multicenter randomized, placebo-controlled dose-ranging weight loss trial with a 12-week treatment period.
Subjects: Two hundred and eighty-one obese but otherwise healthy participants.
Measurements: Weight and obesity-related comorbidities at baseline and at the end of the intervention.
Results: Betahistine, at the doses tested, did not induce significant weight loss. With the exception of headache, no difference in adverse effect profile was noted between placebo and treatment groups. Subgroup analysis revealed that age below 50 years, ethnicity (non-Hispanics) and gender (women) were the strongest predictors of weight loss in this population. When these three factors were combined together, the betahistine 48 mg group (n=23) lost -4.24+/-3.87 kg, whereas the placebo group (n=25) lost -1.65+/-2.96 kg during this time period (P=0.005).
Conclusion: Betahistine, at the doses tested, induced significant weight loss with minimal adverse events only in women below 50 years.