Objective: To determine weight loss efficacy of four thermogenic drugs often used in obesity treatment. Design, Material and Methods: 103 obese women (30 < BMI < 40kg/m²) aged 18 to 55 years-old were assigned to receive in a blind protocol and by random order yohimbine 8mg, triiodothyronine (T3) 25mcg, amminophiline 100mg plus ephedrine 25mcg, phenylpropanolamine (PPA) 25mcg or placebo t.i.d. for 12 weeks. They received a 1,200kcal diet and were evaluated every two weeks for weight, blood pressure, heart rate, adverse events and adherence. Each subject was submitted to bioimpedance and calorimetry analysis in the beginning and in the end of the study. Results: Patients who were taking PPA lost significantly more weight (measured by DBMI) as compared to the other groups in relation to placebo group (p < 0.05). Changes in percentual fat mass, percentual lean body mass and calorimetry analysis showed no significant differences between the groups. Conclusion: PPA can be considered the best drug in respect of short-term weight loss, but we cannot explain this fact on increase in the resting metabolic rate, which was not different among the groups.
Obesity; Calorigenic substances; Yoimbine; Triiodotironine; Aminophylin; Efhedrin; Phenylpropanolamine