Former first lady Barbara Bush was released from Methodist Hospital in Houston on Wednesday after suffering what doctors believe to be a mild relapse of Graves disease, the most common form of hyperthyroidism.
The wife of former President George H.W. Bush was admitted on Saturday morning and was held for a series of routine tests.
A spokeswoman for the family says the 84-year-old hadn't been feeling well for the past week.
"Upon discharge, she was alert, talkative and appeared to be getting stronger as she prepared to return home," hospital spokeswoman Stefanie Asin said.
Mrs. Bush underwent surgery last March for a narrowing heart valve and in 2008 for a perforated ulcer.
Hospital officials said in a statement Mrs. Bush is expected to make a full recovery.