Hi All - I'm becoming a paranoid maniac when it comes to 3.5 lb Coco Chanel following this past weekend's anaphylactic shock incident so I thought I'd check in on another potential issue as a preventative measure. Coco Chanel and I have just made out airline reservations for a Christmas Vacation in Santa Fe, New Mexico. My parents live up in the Sangre de Christo mountains at around 8,500 ft above sea level. Even I get light headed sometimes intermittently the first few days I'm there. Since this will be Coco's first visit to the mountains, shall I anticipate that this might be an issue for Coco -- your insights/advice would be greatly appreciated!! Mama Diane & Miss Coco Chanel