After she gets stung by tracker jackers
In The Book, The Hunger Games, Katniss Began To Suffer From Hallucinations After What?
Tracker Jackers stings from precisely 3 stings
Katniss is sleeping in the tree and rue gets her attention Katniss sees the tracker jackers and she saws their nest off and chucks it into the careers below which causes at least one of them to die the tracker jackers sting Katniss which causes her to hallucinate and pass out but Rue takes good care of her and they form an alliance not long after Rue is killed and Katniss buries her in flowers!
She doesn't get water.
She got stung by a few tracker jackers. Their venom causes hallucinations.
She got stung by tracker jackers. The venom causes the victum to hallucinate and is sometimes used for torture.