What is idiopathic generalised epilepsy?

Terminology: Generalized epilepsy refers to seizure activity that affects the entire brain such as a full blown tonic-clonic convulsion. Idiopathic is term for unknown etiology. But all seizures are caused by abnormal brain function, and there is always some underlying explanation. Just that it is hard to pin down in many situations.

Well....: In brief, electrical abnormalities erupt everywhere at once in the brain. Idiopathic means "presumed genetic but we can't prove it, so we don't really know why you have it." You might check out my YouTube channel "Andrew Reeves Neurology" where I have videos explaining a lot of that. (It's a free resource and is not a commercial thing. Purely for raising the education bar.)