Greece's parliament on Wednesday voted to open an investigation into alleged health scandals going back two decades, involving bribes and inflated prices for medical equipment and medicine.
A broad majority of 187 lawmakers in the 300-seat parliament approved a government proposal to look into suspected mismanagement between 1997 and 2014.
"Everything must be investigated... to clear up whether the public interest was upheld," Prime Minister Alexis Tsipras told the chamber.
The ruling left-wing government says that past socialist and conservative administrations for decades allowed health contractors to overcharge Greek hospitals for equipment, supplies and medicine in return for kickbacks.
"For years, public (funds) were pillaged, hurting social security funds and benefiting powerful interests," the PM said.
Wednesday's move came as Greek magistrates are stepping up an investigation into claims of widespread bribery by Swiss pharmaceutical giant Novartis.
Greece's justice minister last week said Novartis had likely bribed "thousands" of doctors and civil servants to promote its products.
"National health service doctors and state officials were bribed to promote drugs in an illegal and anti-scientific manner," Kontonis said.
The Swiss pharmaceutical giant has also been investigated by American and Chinese authorities, and forced to pay millions of dollars (euros) in fines.
Tsipras said there are also questions over the 2014 takeover of one of Greece's top hospitals, which had previously been managed by the Hellenic Red Cross.