The probe follows reports in the Turkish press which alleged Novartis paid bribes of $85 million (75 million euros) via a consulting company to representatives of the Turkish health ministry in order to "unfairly acquire a market share".
Contacted by AFP, Novartis said it had no comment on the report. But it said a previous probe into Novartis in Turkey, sparked by a complaint by a whistleblower, was dropped by Turkish authorities after
Novartis's own internal investigation in 2014 found no wrongdoing.
The drugmaker said last week it had reached a deal with US authorities to pay $25 million (22.4 million euros) to settle claims that its Chinese units bribed healthcare professionals to boost sales.
And the US last year fined the group $390 million for granting kickbacks to pharmacies that recommended the company's drugs.