"We try to keep him at rest. He would like to re-immerse himself into his frantic activity, but doctors say caution is necessary," he said.
Pictures of Berlusconi's bloodied face dominated Italian newspapers on Monday, with even media usually opposed to the controversial prime minister condemning the attack.
The left-wing daily La Repubblica
said the assault "highlights the degradation of the political climate in Italy".
"Friends and enemies, partisans and opponents must show solidarity" with Berlusconi, it said.
"What is at stake is nothing less than liberty."
James Walston, a professor of Italian politics at the American University of Rome, told Al Jazeera that the attack was likely to see Berlusconi's popularity rise in the short term.
"But whether he is able to use that for political measures ... remains to be seen," he said.
"His supporters are passionate about him, as his opponents are very, very passionate against him. He's a hugely divisive figure."
The alleged assailant, 42-year-old Massimo Tartaglia, was arrested following the attack and placed in an isolation cell, police said.
Tartaglia is said to have thrown a replica of Milan's gothic cathedral Duomo, which has a metal base and dozens of sharp spires, at the prime minister during a political rally.
The attack comes at the end of a difficult year for Berlusconi.
His popularity recently plummeted after accusations of sexual encounters with escorts, a separation from his wife, the loss of immunity prosecution and the restart of two corruption trials.
The prime minister faces allegations that he paid his British former tax lawyer, David Mills, $600,000 to give false evidence in two trials in the 1990s.
Earlier this month, about 350,000 Italians called for his resignation in what they dubbed the "No Berlusconi Day".
In 2004, an Italian bricklayer hurled a camera tripod at Berlusconi, injuring him slightly on the head.