I have to be up, outside, and preferably walking, too. I did have one attack over the summer (while going through an anti depressant change), where I had to lay on the floor with a fan blowing on me. It makes sense, though, if dizziness is part of your panic attacks. My mom has panic attacks where dizziness is the main symptom-- she takes an Antivert and lays down until she can sleep it off.