Signal. I admit that the title of this blog post is somewhat misleading, but please bear with me. Yes, GLP-1 receptor agonists have very little to do with epilepsy, but there is a larger story behind this. In a recent study, nearly 28,000 people taking GLP-1 receptor agonists answered a seemingly simple question: how much weight did you lose, and how bad were the side effects? This simple survey, coupled with genetic data, produced one of the cleanest pharmacogenomic signals seen in recent years. But it also emphasized that the genetics of treatment are often not the genetics of disease, and that matters far beyond obesity and weight loss. Here is why this should make us rethink pharmacogenomics in epilepsy.