Finance Minister Yannis Stournaras was taken to hospital on Thursday where he was diagnosed with a serious viral infection and exhaustion.
The minister was discharged at his own request before returning to the Finance Ministry offices for talks with officials ahead of a scheduled meeting with Prime Minister Antonis Samaras.
Stournaras is the latest in a series of Greek government officials to feel the strain of a punishing schedule of tough negotiations with the troika.
Earlier this month, Justice Minister Antonis Roupakiotis underwent an operation to remove a blood clot from his brain.
In June, former National Bank president Vassilis Rapanos turned down the job of Finance Minister, offered to him by Samaras, citing serious health problems. A few days before that Samaras himself underwent eye surgery. At last Octber's crucial European Union summit, two aides to the then Prime Minister George Papandreou suffered serious health problems. Giorgos Glynos suffered a heart attack ahead of the meeting while Giorgos Zannias developed high blood pressure during the summit and was ordered to stay in his room.