The Ivory Coast forward was stretchered off at Stamford Bridge on Saturday after a mid-air collision with Norwich goalkeeper John Ruddy that was compounded by a heavy fall to the turf.
Chelsea manager Andre Villas-Boas confirmed that Drogba had been knocked out but believes he was left with concussion rather than a potentially more serious injury.
"Didier is showing some signs of recovery now," he said. "He lost consciousness completely on the pitch and I have to be grateful to my players, the Norwich players and the medical staff that they reacted so quickly to a potentially dangerous situation.
"I am happy enough they arrived in time to bring Didier back to consciousness. We are waiting for the full exams of his concussion and hopefully nothing is wrong. I don't know how long he was out for. A couple of minutes I think.
"We hope for his well-being as a person first. He is showing progressive signs of recovery but we need a full exam, which is being done."
Chelsea have now picked up seven points from three Premier League games since Villas-Boas replaced Carlo Ancelotti at the Stamford Bridge helm.
But this victory was by no means straightforward and hinged on a penalty award and red card decision with the score at 1-1.
Referee Mike Jones decided to send off Norwich goalkeeper John Ruddy for upending Ramires in the penalty area, and Frank Lampard converted the spot-kick before substitute Juan Mata, on his debut, made it 3-1 in stoppage time.
Norwich manager Paul Lambert was unhappy with the decision, which came after his captain Grant Holt had cancelled out Jose Bosingwa's early Chelsea opener.
"The penalty turned the game," the Scot said. "I have seen it on the monitor and he has lost control of the ball. He is actually going to ground before he's got it. The referee has only got one take on it but I thought it was harsh."
Lambert was also annoyed by the arrival of one of Chelsea's back-room staff - thought to be first team fitness coach Jose Mario Rocha - in his technical area seconds after Ramires had gone down in the Norwich penalty box.
"It was the guy with the stopwatch round his neck," Lambert said. "I don't know who he is but he has come flying into our area, which I thought was disrespectful.
"I'm not fluent in Portuguese so I don't know what he was saying but if he understands Glaswegian then he'll know what I said. You don't do that."
Villas-Boas made it clear he did not believe any slight had been intended. "I know Paul was excited, not only with that but also with the penalty," he said.
"It is difficult to control your own emotions on the bench but I would find it very strange that my technical staff would be disrespectful of Norwich."
Bosingwa's opener was his first goal since 2008 but was worth waiting for as it was a drive from outside the area that found the top corner.
Holt's equaliser, which came in the 63rd minute, was the result of a breakdown in communications between goalkeeper Hilario and centre-back Branislav Ivanovic.
Both Chelsea players went for a cross from Kyle Naughton but succeeded only in letting Holt nip in and hook the ball into an empty net.
Lampard's penalty was scored with just eight minutes remaining and Mata, the ?£23 million signing from Valencia, got the third to mark his debut in style as he seized on a loose ball in the box and slotted home.
Source: AFP
Source: AFP