Frullani is the second athlete to test positive for drugs at the Games. The German ski federation said earlier on Friday one of their biathletes had also failed a doping test for a stimulant. It did not name the athlete.
The 34-year-old Frullani, a former track and field athlete, tested positive for the substance dymetylpentylamine, also found in nasal decongestants, and has left the village.
Italian officials said they had got the green light from the International Olympic Committee to replace Frullani in their four-man bobsleigh team with the competition set for Sunday, the final day of the Olympics.
"The Italian Olympic Committee (CONI) now needs to sort out the composition of the bobsleigh team which Frullani was part of, to make it back up to four," CONI said in a statement.
"They have requested that the athlete be replaced with the reserve Samuele Romanini and clearance for this has been received from the IOC."
Until Friday, Russia's first Winter Games had not had a positive doping case.
Photograph: Stefan Wermuth/Reuters
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