The bluehead was really badly knocked out.
According to Eleen, the dosage of the medicine that was forcefully fed to him was just a bit lower than what could kill people. It was done to make sure he wouldn't wake up in the middle of their discussion and make another fuss. Since the man's body showed an unnatural resistance against the medicines the doctor made, she just increased the dosage and the amount to put him to sleep. But it seemed that, no matter how resistant the body was, that amount wasn't really easy to deal with. It was proven by seeing how the person was deep asleep until the evening of the next day.
