panic disorde
"I've had severe panic attacks while primarily driving on interstate highways and through mountains for 30 plus years. I rarely have attacks driving on most other types of roads and conditions.  I've been on Paxil for 5 years now and it is truly a life saver for me.  I choose however, and contrary to most advice, not to be on it all the time as it does numb the senses.  

Twice yearly I drive from Florida to Indiana and choose to take 20 mg/day for one month prior to my trip and 40 mg/day a couple of days prior to my trip.  For the most part I can drive successfully with no attacks.  Occasionally I will still have what I call a "break through"- sort of a rush sensation but not as severe as a panic attack.  I have no problems coming off it."