Blood and urine samples did not find any trace of illicit substances or excessive alcohol and further medical tests have been carried out this week.
Wallabies head coach John Connolly said: "He (Giteau) is okay. He has trained well today, no problems. The doctor gave him the thumbs up.
"It has never been red flagged with us before. It was a one off and it does happen - the doctor is very comfortable with it. He (Giteau) has trained well."
The issue follows hot on the heels of the two-match suspension handed down to Australia team-mate Lote Tuqiri for turning up late at a Wallabies training session still inebriated following celebrations on the same night as Giteau's collapse.
But Connolly said the Australian Rugby Union had no further concerns over any wrongdoing in the case of Giteau.
"He (Giteau) raised it with Martin (Raferty, the team doctor) on Monday morning so there are no concerns for us. As far as we are concerned it is all clear so it is fine," he added.
Connolly put the matter down to the rigorous pressure international players are under.
"These players are under a lot of stress," said Connolly. "The night before they might not get back to the hotel until midnight, he probably doesn't get to bed until 2 or 3 o'clock by the time he winds down, if then. You are travelling all next day and then you go out - there is a lot of stress and pressure on them.
"I have seen it happen a couple of times over the years - the odd player not feeling particularly well after a game and he has had to sit down and feeling a bit faint - usually within 24 hours.
"It has happened once before with one of the players when I was coaching Queensland where the player felt faint at the recovery session the next day."