The 31-year-old has not been seen in a Reds shirt since New Year's Day owing to the Africa Cup of Nations and a muscular problem, which he sustained during the group stages of the continental tournament.
Jurgen Klopp confirmed that Salah had returned to full training this week and would be in contention, but the ex-Chelsea man has been overlooked for a place in the first XI, as Diogo Jota, Darwin Nunez and Luis Diaz form an unchanged attacking trident.
While Salah is now fit again, Alisson Becker - absent from the win over Burnley due to illness - misses a second successive fixture owing to a reported hamstring issue, allowing Caoimhin Kelleher to guard the posts again.
Two changes arrive in the Liverpool backline, as Ibrahima Konate displaces Jarell Quansah following his return from suspension, while Conor Bradley - who has sat out the last two fixtures due to his father's death - deputises for the injured Trent Alexander-Arnold.
As for Brentford, Thomas Frank is without integral defender Ethan Pinnock with an ankle problem, so Kristoffer Ajer is brought into the first XI, while Yoane Wissa and Frank Onyeka are back on the bench after their AFCON exploits.
Brentford: Flekken; Ajer, Collins, Mee; Roerslev, Janelt, Jensen, Norgaard, Reguilon; Toney, Maupay
Subs: Strakosha, Wissa, Zanka, Ghoddos, Onyeka, Lewis-Potter, Damsgaard, Yarmoliuk, Baptiste
Liverpool: Kelleher; Bradley, Konate, Van Dijk, Robertson; Jones, Endo, Mac Allister; Jota, Nunez, Diaz
Subs: Adrian, Gomez, Salah, Gakpo, Elliott, Tsimikas, Graveberch, McConnell, Quansah