Real Madrid have revealed that Michael Essien has been recently sidelined with an allergic reaction to medicine that was given to him by the club.
The midfielder, who is currently on loan at the Santiago Bernabeu from Chelsea until the end of the season, has missed the last two games for the La Liga champions.
"He has had an allergic reaction to some medicine," said Madrid assistant coach Aitor Karanka.
Madrid continue the defence of their Primera Division crown on Saturday when they travel to Real Betis.
