Green’s Dictionary of Slang

beat up v.

[fig. use of SE beat up, to attack plus foxhunting imagery]

1. to visit, to pay a (surprise) call.

[Ind]J.W. Kaye Peregrine Pultuney II 54: Pultuney determined [...] that he would ‘go and beat up his old aunt’.

2. (orig. US, also beat up on) to nag, to harass.

[UK]Wodehouse Gentleman of Leisure Ch. xv: ‘Rehearsal after lunch. Don’t be late.’ And he was off to beat up the rest of the company.
[US]E. Pound letter 7 Jan. in Paige (1971) 250: A guy named Collis is beating up the Britons.
[US]C. Himes ‘A Modern Fable’ in Coll. Stories (1990) 417: You take the son of a bitch yourself [...] You take him and beat him up for bread.
[US]G.V. Higgins Cogan’s Trade (1975) 86: I beat up on my family and get some dough.
[UK]K. Sampson Powder 318: Don’t beat yourself up over it, man!

3. to promote, to encourage.

[Aus]Bulletin (Sydney) 24 Nov. 13/4: Beat up another engagement for that night.
[UK]‘Sax Rohmer’ Dope 90: Of course, her game is beating up clients for the Limehouse dive.