How long does brain swelling usually last?

Brain feels like it's swelling at times?

• A couple times a week at any random moment, my brain feels like it's swelling and it feels like my head will burst from the pressure and that I will pass out. I get really light headed and have to stop whatever I'm doing to sit down or hold onto something so I don't fall over. It's a different feeling than I get when I have a headache. This has been happening for a couple months now, I haven't gone to the doctor because I've been so busy with other things, anyway, just getting a few suggestions on what it could possibly be, I will be going to the doctor soon because it's getting worse. Thank you.

• Answer:

  Sounds like dehydration. Your brain is in fact shrinking rather than swelling. You need to drink much more water throughout the day.