The dog owner was found unconscious in his Milan apartment by firemen, La Repubblica reported. He is thought to have been attacked by one of this two pitbulls.
His girlfriend raised the alarm after failing to hear from her boyfriend.
The man, who suffers from diabetes, is now in a serious condition in hospital.
It is unclear whether the man’s diabetes caused him to lose consciousness before he was bitten, or whether the pain from the bite prompted him to collapse, the newspaper said.