Please have your doctor tell the infusion service miniumum 4 hours as per his orders.... it is not true - as others have mentioned also - that you only may have a reaction the first time... again, these nurses are trying to speed thru their days.... some are great - some are in a hurry..... I had a reaction hours after receiving an infusion that was increased from 4 1/2 to 3 hours - woke up gasping for breath - immediately called my doc who had a fit and said NEVER LET THEM DO THAT AGAIN.