The PS had been remanded at the Langata Women Prisons.
The PS is reported to have fainted on Tuesday night and was thereafter rushed to Nairobi Hospital.
PS Omollo, NYS Director-General Richard Ndubai and 22 other suspects implicated in the NYS scam were to spend at least one week in jail as they await a ruling on their bail application.
The PS and the Director General who resigned from their positions last week appeared in 10 files and faced multiple charges of abuse of office, failure to comply with the guidelines and procedures on public finance management as well as conspiracy to commit economic crime.
The Director of Public Prosecutions (DPP) Noordin Haji had said he had sufficient evidence to press charges against the arrested suspects in connection with the latest NYS scam.
"They will be charged with conspiracy to commit an offense of corruption, willful failure to comply with applicable procedures and guidelines on the management of public funds, breach of trust, neglect of official duty, abuse of office, fraudulent acquisition of public property and fraudulent making payments from public revenues," the DPP said.