University of Pennsylvania Medical Center Guidelines for Antibiotic Use

Clinical Setting	Empiric Treatment	Likely Pathogens	Definitive Treatment	Dosage Regimen	Duration
Endophthalmitis
Post-operative1	ceftazidime + vancomycin2	S. aureus	TMP/SMX3 + vancomycin (intravitreous)	8-10mg/kg/d TMP IV in 3-4 divided doses	Depends on clinical setting
		coagulase negative staphylococcus	vancomycin + vancomycin (intravitreous)	see this link	Depends on clinical setting
		P. acnes	TMP/SMX3	8-10mg/kg/d TMP,IV in 3-4 divided doses	Depends on clinical setting
		P. aeruginosa (rarely)	levofloxacin + gentamicin (intravitreous)	500mg IV q 24hour	Depends on clinical setting
Hematogenous (i.e. SBE)	see endocarditis section (intravitreous antibiotics may be useful)
Orbital Cellulitis	ampicillin/sulbactam +/- vancomycin 4,5	S. aureus	cefazolin6	500mg IV q 8 hour	Depends on clinical setting
		Streptococcus spp.	cefazolin6	as above	Depends on clinical setting
		Enterobacteriaceae	TMP/SMX6	8-10mg/kg/d TMP IV in 3-4 divided doses	Depends on clinical setting
		H. influenzae	TMP/SMX6	as above	Depends on clinical setting

¹Vitrectomy may be required

²Dosage Regimens: ceftazidime 1 gm IV q 8 hour, vancomycin-see Table V

³Achieves superior intra-ocular penetration

⁴Dosage regimens: ampicillin/sulbactam 1.5-3 gm IV q 6, vancomycin-see Table V

⁵Requires broad coverage until cavernous sinus thrombosis, orbital apex syndrome, and sinusitis ruled out

⁶Decongestants may be an important adjunct to therapy when sinusitis present

updated 4/1/2003

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