The England striker is allowed to train from this weekend onwards, but cannot play for Brentford until January 17 due to his eight-month ban for 232 breaches of FA betting rules.
The Bees, who visit Newcastle on Saturday, have started the season excellently in the absence of their top striker and are one of six teams still unbeaten in the Premier League after four matches.
Manager Thomas Frank said of Toney: “He’s very happy to be allowed back into football — to be around team-mates that he loves. No doubt it will give us a lift.
“He hasn’t trained or played a team session, so we of course need to adapt him a bit. We have made a plan for him for the next 16 weeks. We will try to work on his strength and other development areas.
“I’m massively proud of Ivan. The resilience he’s shown throughout his life, he should be an example for a lot of footballers.”