My Sister Was Admitted With A Stomach Ulcer. She Was

My sister was admitted with a stomach ulcer. She was in hospital from Sunday to Tuesday. She had thrown up alot of blood and was given blood. She is from out of town. She is to fly home Friday evening, a one hour flight. The doctor at the hospital said she could fly home on Friday. She is on iron medication because she is at the border line level of being anemic. She still gets dizzy sometimes. Is it safe for her to fly?