Approved for long-term weight management in patients with obesity.
Bupropion is a dopamine/norepinephrine reuptake inhibitor approved for depression and for smoking cessation.
Naltrexone is an opioid receptor antagonist approved to treat alcohol and opioid dependence.
Bupropion in obesity studies is associated with a 2.8 kg plecebo-subtracted weight-loss at 6 to 12 months.
Bupropion is suspected to stimulate secretion of anorexigenic alpha-melanocyte-stimulating hormone from pro opiomelanocortin-producing hypothalamic cells.
Naltrexone has little efficacy in weight management as a single agent, however it counteracts the auto inhibitory reactions of bupropion stimulated endogenous opioids.
Naltrexone and bupropion reduce appetite and food cravings through different mechanisms that stimulate propriomelanocortin neurons.
Randomized control studies including 9949 adults with obesity found the combination of agents associated with a 4.1% greater weight loss than placebo.
Combining naltrexone with bupropion and intensive behavioral therapy is associated with a 9.3% weight loss at 12 months compared with 5.1% weight loss for placebo with intensive behavioral therapy.
Naltrexone and bupropion have fewer cardiac effects on risk factors than does some other anti-obese medications.
Common and effects of N-B include nausea, constipation, headache, vomiting, dizziness, insomnia, and xerostomia.