The official Egyptian news agency says the country's former president Hosni Mubarak is weak and refusing solid food.
Mr Mubarak, who was overthrown in February in a popular uprising, is due to stand trial next week accused of ordering the killing of protesters.
The head of the hospital where Mr Mubarak is detained in Sharm al-Sheikh said he was depressed, has lost weight, and was not eating enough to keep him alive, the MENA agency says.
The BBC reports that critics see Mr Mubarak's illness as a ploy to avoid going on trial.
More than 840 people died in the February uprising.