Our research group has dealt with injection-induced lip hypertrophy (IILH) in insulin-treated subjects for over a decade, focusing on causes and consequences, education, prevention and treatment, comorbidities, and related complications. Stimulated by an excellent Review that recently appeared on the pages of this Journal, we want to contribute insight into IILH. This brief Commentary underlines some key concepts on how to identify, prevent and cure them, pointing out salient aspects derived from our research to provide the scientific community with an as complete as possible overview of evidence-based knowledge and highlight the need for further experimental insights.