MK Avigdor Lieberman's daughter, Michal, fell ill on Monday, during a questioning session run by the police's National Fraud Unit.
An ambulance was called to the office, and she was released following a medical examination.
Lieberman's daughter was detained on Sunday along with five other suspects, as part of a two-and-a-half-year-long investigation into Lieberman, who is suspected of accepting a bribe via a consultancy firm registered by his daughter.
Lieberman is also suspected of channeling funds into an overseas account, which detectives believe went to fund an election campaign.
Yaakov Lappin contributed to this report.