I only know about Gliclizide and yes you need to eat when you take this. It can cause a hypo if you take it without eating. When I was on it I used to take it 20 minutes before my meal, but it does continue working for longer. If I didn’t eat I didn’t take it
And if you've been low carbing or losing weight, it is best to go back to doctor in case doses need adapting, as they were based on where you were when you started