Samaritan Infectious Disease - Antibiotic Guidelines

Antibiotic Guidelines
Central Western Oregon

Syndrome	Primary Rx	Alternate Rx	Comments
Pharyngitis, streptococcal	Penicillin V 500 mg qid x 10d	Erythromycin Clindamycin Cephalexin	Diagnosis is based on streptococcal throat screen or culture.
Sinusitis, acute	Amoxicillin 500-1000 mg tid Azithromycin 500 mg x 1; 250 mg daily thereafter Doxycycline 100 mg bid	Amoxicillin/clavulanate 2nd gen cephalosporin Resp quinolone TMP/SMX	Symptoms should have been present for more than 7 days. Antibiotic therapy is not always indicated.
Sinusitis, chronic	Value of antibiotics is uncertain; consider ENT and/or ID consultation.
Bronchitis, acute	Antibiotics are not indicated.		This is usually viral in origin.
Otitis media, acute	Amoxicillin-- Peds 15-30 mg/kg tid Adults 500-1000 mg tid	2nd generation cephalosporin Amoxicillin/clavulanate Azithromycin Ceftriaxone	Antibiotics are not always required.
COPD, acute exacerbation	Doxycycline 100 mg po bid Amoxicillin 500-1000 mg po tid	TMP/SMX 2nd gen cephalosporin Azithromycin Respiratory quinolone	Antibiotics are not always indicated.
Pneumonia, community acquired - outpatient	Azithromycin 500 mg po daily Doxycycline 100 mg po bid	(2nd gen cephalosporin or Amoxicillin) + Azithromycin	Use respiratory quinolone if significant comorbidities present.
Pneumonia, community acquired - inpatient, non-ICU	Ceftriaxone 1-2 gm IV qd + Azithromycin 500 mg qd	Resp quinolone	Streptococcus pneumoniae, Haemophilus influenzae, "atypicals" are common causes of this syndrome.
Pneumonia, community acquired - inpatient, ICU, non-pseudomonal	(Ceftriaxone 2 gm IV qd or Amp/sulbactam 3 gm IV q6) + (Azithromycin 500 mg qd or Resp quinolone)	Resp quinolone + Aztreonam	Add Vancomycin (or linezolid) for MRSA risk
Pneumonia, community acquired - inpatient, ICU, pseudomonas	(Cefepime 2gm IV q8 or Pip/tazo 4.5 gm IV q 6 or Imipenem/Meropenem) + (Cipro 400 mg IV q12 or levofloxacin 750 mg qd)	(Pip/tazo or Cefepime or Imipenem/ Meropenem) + Tobramycin + Azithromycin Aztreonam + (Levofloxacin or Moxifloxacin)	Add vancomycin (or linezolid) for MRSA risk
Pneumonia, healthcare acquired	Piperacillin/tazobactam 4.5gm iv q 6hr plus (Gentamicin, Aztreonam, or Resp quinolone) +/- Vancomycin	(Cefepime or Imipenem/Meropenem) + Resp quinolone Clindamycin + Resp quinolone + Aztreonam Add vancomycin if MRSA is supected	Pneumonia acquired by persons in long term care, frequent hospitalization, etc.
Pneumonia, aspiration	Clindamycin 900mg q 8-12 hr +/- (3rd gen cephalosporin,aztreonam, or resp quinolone)	Ampicillin/sulbactam +/- (Gentamicin, Aztreonam, or quinolone)	This applies to community acquired aspiration; for healthcare aquired aspiraton, see pneumonia, heathcare acquired.
Cystitis, uncomplicated	TMP/SMX DS po bid x 3d	Nitrofurantoin (7 day course) Ciprofloxacin (3d)	Infection in young women without complicating urologic abnormalities. E. Coli are the most common cause of this syndrome.
Pyelonephritis, uncomplicated	Ciprofloxacin x 5-7 days	TMP/sulfa x14d Augmentin x 14d Ceftriaxone (IV)	No complicating urologic problems; p.o. beta-lactams not as effective as FQ's; 10-20% FQ and T/S resistance (E. Coli)
Pyelonephritis, complicated	Ampicillin 2 gm IV q 6 hr + Gentamicin IV Piperacillin/tazobactam	(Gentamicin or Aztreonam) + Vancomycin Imipenem	Complicated pyelo includes patients with obstruction, stones, urologic instrumentation, etc.
Cellulitis, mild	Dicloxacillin 500 mg po qid Cephalexin 500 mg po qid	Clindamycin	Beta streptococci are the typical cause of this syndrome; suspect MRSA if purulent skin disease is present - see MRSA algorithms.
Cellulitis, severe	Cefazolin 2 gm IV q8 hr Nafcillin 2 gm IV q 4-6 hr	Clindamycin Vancomycin	These patients may require hospitalization; if MRSA is suspected, see MRSA algorithm.
Diabetic foot infection, outpatient	Dicloxacillin 500 mg po qid Cephalexin 500 mg po qid Augmentin	Clindamycin + (TMP/SMX or Ciprofloxacin)	If MRSA is supected, see MRSA algorithm.
Diabetic foot infection, inpatient	Ampicillin/sulbactam 3 gm IV q 6h Clindamycin 900 mg IV q8-12h + (Gentamicin or Ciprofloxacin)	Piperacillin/tazobactam	Avoid gentamicin in older diabetics or those with renal insufficiency; use vancomycin if MRSA likely.
Peritonitis; intra-abdominal, intra-pelvic abscess	Zosyn 3.375 gm q 6 hr Gentamicin + metronidazole + ampicillin	Ceftriaxone + metronidazole Ampicillin/sulbactam + gentamicin Aztreonam + metronidazole + vancomycin	Infection is often polymicrobic; GNR's and anaerobes are common etiologies.
Clostridium difficile associated disease	Metronidazole 500 mg po tid x 10 - 14d	Vancomycin 125 mg po qid x 10 - 14d	Vancomcyin is likely more effective for severe disease; epidemic strain causes more relapses, complications.
Arthritis, septic	(Cefazolin 2 gm IV q 8 hr or Nafcillin 2gm IV q 4-6 hr) +/- Gentamicin Ceftriaxone 1 gm q 24 hr if gonorrhea is suspected	(Clindamycin or Vancomycin) +/- (Gentamicin, Aztreonam, or Ciprofloxacin)	Acute, community acquired, non-prosthetic joint. If MRSA is suspected, see MRSA algorithm-severe.
Bite, animal or human, outpatient	Amoxicillin/clavulanate 875 mg po bid	Clindamycin + (TMP/SMX or Doxycycline)	Pasturella multocida is a common cauae of animal (cat or dog) bite infections.
Bite, animal or human, inpatient	Ampicillin/sulbactam 3 gm IV q 6 hr	Ceftriazone Clindamycin + (TMP/SMX or Doxycycline)	Pasturella multocida is a common cauae of animal (cat or dog) bite infections.
MRSA, mild to moderate	TMP/SMX or doxycycline (clindamycin if susceptible)	Linezolid	MRSA is more reliably susceptible to TMP/SMX or doxycycline than clindamycin.
MRSA, severe	Vancomycin IV	Linezolid Daptomycin Ceftaroline Tigecycline	Daptomycin ineffective for pneumonia; Avoid tigecycline for bloodstream infection.
Cutaneous abscess, carbuncles	Doxycycline 100 mg po bid TMP/SMX DS po bid	Clindamycin Linezolid	I&D may be sufficient; obtain cultures

Back to Guideline Table

These guidelines are created by physicians ofSamaritan Infectious Disease, Corvallis, OR. They are created based on likely antibiotic effectiveness and local antibiotic susceptiblities and are intended as empiric recommendations only. Individual patient circumstances may necessitate alternate choices.
Doses are for adults with normal renal function.
2nd gen cephalosporins include cefuroxime, cefpodoxime; Resp quinolones include levofloxacin, moxifloxacin