They were released pending investigation after agreeing to give urine samples, judicial sources said, adding that the results had not yet been released.
Morsi's other son, Osama, had dismissed the accusations, saying the authorities were "fabricating the case" and that his brother's arrest was an attempt to "defame the family".
Morsi and his Muslim Brotherhood have been the target of a relentless government crackdown since the Islamist was ousted last July after just a year in office.
Amnesty International says that more than 1,400 people have been killed, mostly Morsi supporters, in street clashes since his ouster.
Morsi himself and several Brotherhood leaders have been put on trial.
-----------------------------------------------------------------
Morsi's other son, Osama, had dismissed the accusations, saying the authorities were "fabricating the case" and that his brother's arrest was an attempt to "defame the family".
Morsi and his Muslim Brotherhood have been the target of a relentless government crackdown since the Islamist was ousted last July after just a year in office.
Amnesty International says that more than 1,400 people have been killed, mostly Morsi supporters, in street clashes since his ouster.
Morsi himself and several Brotherhood leaders have been put on trial.
-----------------------------------------------------------------