GCG and obesity due to melanocortin 4 receptor deficiency: As mentioned, GLP-1-based drugs are used to treat obesity [6] and type 2 diabetes [7], but transient GI events such as nausea and vomiting are reported [51]; however, the effect of these drugs on metabolic health (by reducing body weight and blood glucose levels and having cardio-, reno-, and neuro-protective effects [52,53]) generally outweighs the side effects.