"Steven Gerrard today began a course of antibiotic treatment for an infection related to an ongoing groin problem," the Premier League club said on their website on Saturday.
"He is expected to remain in hospital for several days while the precautionary procedure is completed... and is expected to be available for selection in September."
The England midfielder missed the club's pre-season tour of Asia this month in order to try to regain full fitness for the start of the new season on August 13.
Gerrard missed the end of last season because of the groin problem and needed surgery.
Liverpool kick off the season at home to Sunderland.
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