Flood, 28, was injured early in the match at Welford Road - with Leicester's official website reporting Flood collided with Ulster's Dan Tuohy, who was yellow-carded by referee Tim Wigglesworth.
But Flood calmed fears about his condition by tweeting a picture of himself in a neck brace, adding the caption: "How's everyone else's day going?"
The club announced via Twitter: "On Toby Flood, Paul Burke says he was taken to hospital where he is conscious and going through standard medical checks."
- Nature & Environment
- Toby Flood