The Brazilian injured his shoulder against Swansea on Monday night and requires surgery that will keep him out until the end of October.
"Liverpool hope to have the 21-year-old back in contention again towards the end of October."
The injury is likely to rule Coutinho out of four Premier League clashes as well as the League Cup tie at Manchester United.
The matches Coutinho are likely to miss are home clashes against Southampton and Crystal Palace and trips to Sunderland and Newcastle.
Liverpool are likely to target the match at home against West Bromwich Albion on October 26 for his return.
Brendan Rodgers' side are currently top of the Premier League after having won three and drawn one of their four Premier League fixtures.