Omg this is me too!! At first my doctor thought it could maybe some form of seizure because my arms get so shakey. They feel weak, I get sort of confused, light headed, suddenly feel exhausted, I am starving, anxious (palpitations) and I have to sit/lay down. I have found, personally, it's because I need SALT. I buy LiquidIV (pouches of a salty, electrolyte type of drink mix, each one has 500mg of sodium) and I pour 2 into a glass & fill it with water. (If your episode is really bad just do like 2 cups (16oz) of water so you get the salt down more quickly, but definitely keep drinking water. This literally makes these "episodes" as I call them go away within a matter of minutes and I'm back to feeling totally normal within 15 minutes if not sooner. (Everyone is different though.) But I encourage you to try this if you don't have any clue what's going on and have POTS. Also, after drinking the Liquid IV, a salty snack wouldn't hurt to help with the hunger. Crackers, a pickle anything salty. I keep a bottle/ pitcher of water near where I sit/work most of the day and I have the salt packets stashed all over the house & in my purse. My understanding is the more we stay on top of getting enough salt these episodes should happen less ,,& less. I TRY to have 2 IV packets everyday on the morning to sort of jump start the day. And haven't been having these symptoms hardly at all. I really hope this helps you!!