THIS EMPLOYEE WAS UNDER MEDICAL TREATMENT FROM HIS PERSONAL DOCTOR FOR HEALTH CONDITIONS UNRELATED TO WORK. THE EE CAME TO WORK AND WAS IN THE PROCESS OF LOADING TRUCKLOAD OF 50 LB BAGS ON PAL LETS INTO A VAN TYPE OVER-THE-ROAD TRUCK. BEFORE LOADING COULD TAKE PLACE THE EE HAD TROUBLE BREATHING. THE EE WAS TAKEN TO THE ER FOR TREATMENT. DR STATEMENT ON REPORT LISTED AS AN ILLNESS.