The Brazilian, who spent almost seven weeks nursing a shoulder problem, returned to action in the Reds' 2-0 defeat to Premier League leaders Arsenal last weekend.
"I´m very happy to be back," Coutinho told the club's official website. "I had six very difficult weeks and thank God I've made my comeback, but on the other hand I was sad due to the result [at Arsenal]. However, that's over now and we must concentrate on our upcoming matches."
Liverpool are currently third in the league table, five points off the top.