Benjamin Netanyahu was rushed to hospital for tests following an illness.
Israel‘s prime minister “is suffering from a high fever and is coughing,” a spokesman for the 68-year-old said.
He was taken to a hospital in Jerusalem.
Mr Netanyahu’s personal physician believes he had not fully recovered from an illness two weeks ago, the spokesman said.
Dr Tzvi Berkowitz thought his symptoms had worsened as a result and therefore decided he should undergo further tests at hospital.
Mr Netanyahu left hospital late on Tuesday night following the tests.
“I am on my way home. Sure some rest and hot soup will put things right,” Mr Netanyahu said on Twitter shortly after midnight.
“The prime minister has completed a series of tests and will be released home tonight,” a statement from his office said earlier.
“The tests showed a mild viral illness in the upper respiratory tract,” it added.
The 68-year-old fell ill in mid-March and cancelled his public schedule for five consecutive days.
Mr Netanyahu’s illness has come at a stressful time for the right-wing prime minister, who is under police investigation for corruption in three different cases.
On Monday, he was questioned along with his wife and his son by Israeli police over his alleged dealings with the country’s largest telecommunications company — one of three cases weighing on his political future.
It was the second time Mr Netanyahu had been questioned in the investigation into allegations he awarded regulatory favours to Bezeq Telecom Israel in return for favourable coverage on a news site the company’s owner ownes.
Both Mr Netanyahu and Bezeq have denied wrongdoing.
So far, partners in his governing coalition have stood by him, saying they are awaiting the attorney general’s next moves.
Surveys have shown about half of Israelis believe the police over the prime minister and think he should step down, while a third think he should remain in office.
Support for Mr Netanyahu’s Likud party remains strong in opinion polls.