Peritonsillar/Retropharyngeal Abscess

Patient Population: Pediatric

Need for drainage/source control of head and neck infections should be evaluated carefully in consultation with Pediatric Otolaryngology, Head and Neck Surgery. If initial non-operative management is chosen, a narrow spectrum regimen (i.e. without vancomycin) is encouraged to facilitate transition to oral therapy. 

ID consultation is recommended for head and neck infections occurring in immunocompromised patients, and for those with atypical features, chronic course, or lack of response to first line therapy. 

Condition Major Pathogens  First Choice Therapy Alternative Therapy Comments
Peritonsillar/ retropharyngeal abscess  

Group A streptococcus 

Staphylococcus aureus 

Oral anaerobes 


Ampicillin-sulbactam (Unasyn)
50 mg ampicillin/kg/dose (max 2000 mg ampicillin/dose) IV q6h  

If patient has airway compromise, extensive abscess that will be drained, or history of documented MRSA infection or carriage within the last 6 months:  

ADD Vancomycin  

(follow link for dosing & monitoring)   


Outpatient/step down therapy

Amoxicillin-clavulanate (Augmentin)
45 mg amoxicillin/kg/dose (max 1000 mg amoxicillin/dose)* enterally bid  

Penicillin or cephalosporin allergy with higher risk for allergic reaction

10 mg/kg/dose (max 900 mg/dose) IV q8h  


10 mg/kg/dose (max 600 mg/dose) enterally tid 

Urgent OHNS consult recommended to evaluate need for source control  

Consider ID consult (see details above) 

Duration: 10-14 days based on severity and response to treatment 

If Vancomycin was started and MRSA not recovered from drained abscess, discontinue Vancomycin 

*See guidance on Amoxicillin-Clavulanate maximum dosing and formulations 

Pediatric Empiric Antimicrobial Therapy Guidelines

This is a subsection of the UCSF Benioff Children’s Hospitals Empiric Antimicrobial Therapy Guidelines, developed by the Pediatric Antimicrobial Stewardship Programs at each campus to inform initial selection of empiric antimicrobial therapy for children at the UCSF Benioff Children’s Hospitals and affiliated outpatient sites. 

These are guidelines only and not intended to replace clinical judgment. Modification of therapy may be indicated based on patient comorbidities, previous antibiotic therapy or infection history. Doses provided are usual doses but may require modification based on patient age or comorbid conditions. Refer to Pediatric Antimicrobial Dosing Guideline for further guidance on dosing in children, and Neonatal Dosing Guideline for infants < 1 month of age. Consult a pediatric pharmacist for individualized renal or hepatic dose adjustment. Durations provided are usual recommendations for patients who are responding appropriately to therapy. For additional guidance, please contact Pediatric Infectious Diseases (ID) or the Pediatric Antimicrobial Stewardship Program (ASP) at the campus where your patient is receiving care.  

For questions or feedback about these guidelines, please email primary content owners, Rachel Wattier, Pediatric ASP Medical Director at BCH SF and Prachi Singh, Pediatric ASP Medical Director at BCH OAK. 

The content of these guidelines was updated in July 2021. See Summary and Rationale for Changes (password login to Box needed) for detailed explanations of the content changes.