Always susceptible to:
Vancomycin
Levofloxacin
Linezolid
Generally susceptible to:
Penicillins
Cephalosporins
Variably susceptible to:
TMP-SMX
Macrolides
Clindamycin
Resistance to penicillin and cephalosporins exists which is why vancomycin is usually part of empiric therapy for meningitis.
For invasive infections, susceptibility profiles with MIC data should be obtained.