I suffer from drop attacks. I can go very dizzy really quickly for no reason and then just collapse. I also blackout when getting blood taken. I have suffered from these since I was very young and doctors don't know what causes mine. I have had so many tests done but they are always inconclusive. I am on medication to help with the dizziness but for me it doesn't really work. It's called Betahistine and it's for veryigo and balance issues. Hope that helped x

That often happens to me but with a hot flash. It also seems to be common for me in stores--grocery, clothing, etc. Get suddenly hot, sweaty, and lightheaded. Also happens randomly after being in a store for a while, sitting at work, etc.

Yeah I experience this it's usually when my fatigue is very severe and my body is telling me I really need to have a rest properly and usually after a couple of days or sometimes a good week the symptoms with vanish until the next time I'm struggling with the fatigue badly again.

Yes I do I feel really dizzy and sick and feel like I'm going to faint

Sounds like Orthostatic Hypotention. Blood pressure drops on standing, standing still a long time or in heat which causes fainting unless you sit down.