What do systematic reviews say?

Monotherapy vs combination therapy compared

Monotherapy showed no clear difference in all‐cause mortality—different beta lactam compared with combination therapy compared (low certainty).

• Beta lactam antibiotic monotherapy versus beta lactam‐aminoglycoside antibiotic combination therapy for sepsis 2014 · Cochrane Headline outcomes only
  RR 0.85 [0.71, 1.01]
  31 studies · 4146 participants
  Low