What Causes Recurring Bouts Of Body Tremors And Sweating With Palpitations And Abdominal Pains?

My dad is 50, and for several years he has "episodes" usually at night. It starts with an upset stomach and says it feels like his heart is beating in his head...but it don't hurt. He gets kind of Shakey, his body turns red and he sweats badly, and his breathing seems a little labored. He usually goes to the bathroom if he can walk and has loose stool, and feels better. If he don't get to the bathroom he passes out for a bit. Docs here don't know what's wrong....can you help with any thoughts? I'm sorry for wasting your time...I don't have the money for this. My mistake! I thought it was free. We will just keep trying with docs here. Thank you though...very much.