World Health Organization chief Tedros Adhanom Ghebreyesus has been hospitalized in Rio de Janeiro's Hospital Samaritano Barra da Tijuca, local newspaper O Globo reported on Thursday.
Tedros presented with "symptoms of labyrinthitis and an hypertensive crisis," after showing signs of being unwell earlier this week on the sidelines of the G20 summit, it said.
According to the report, Tedros was examined on Monday by health professionals on duty at the G20 summit and given medicine for high blood pressure, but was released once he was stable.
Tedros remained under observation at the hospital on Thursday morning, the report added.
The G20 summit in Rio ended this week with calls for cooperation on climate change, poverty reduction and tax policy.
