Naltrexone/bupropion (Mysimba - Orexigen Therapeutics Ireland Limited) is a fixed-dose combination product for the treatment of adults who are obese or overweight with at least one weight-related comorbidity, as an adjunct to diet and lifestyle modifications. Originally licensed by the European Medicines Agency (EMA) in 2015, it has recently been launched in the UK. Here, we review the evidence for its efficacy and safety and consider its place in therapy.