The patient must be suffering from a serious Pneumonia
. I see 3 antibiotics in the list, but all are of a different bacterial spectrum. Usually 2 antibiotics are prescribed to counter mixed organisms in Pneumonia. The other antibiotic could be to counter another infection elsewhere in the body- may be the bed sores?
If the decision to prescribing antibiotics for the pneumonia was based on Culture and Sensitivity report of sputum, then it must be correct.
I don't consider this an antibiotic overdose.
Wishing you and the patient good health.