Travelling by plane?

I wondered if anyone here is experienced at travelling with POTS? Were you able to take your electrolytes on the plane? I buy the UK “Bulk Electrolytes” brand and it just looks like a bag of white powder, which I’m worried about putting in my suitcase lol.

Also, how was the plane trip itself? I obviously can’t take electrolyte water through departures, but ordinary water just goes straight through me and doesn’t help at all, so it’s safe to say I’m going to feel very unwell. Has anyone found ways to make it easier? Did the plane itself make you dizzy?