Pediatric Appendicitis Clinical Algorithm

The following clinical algorithms were developed for management of pediatric patients with suspected or established appendicitis: 

Click here for a PDF copy of the full guideline.

Follow algorithm below for initial management: 

Follow algorithm below for patients with perforated appendicitis:

Pediatric Appendicitis Clinical Algorithm Antimicrobial Dosing:


Appendicitis (All Types)

Pre-operative and Intra-operative Dosing  

 Gangrenous Appendicitis Post-operative Dosing 

 Perforated Appendicitis

Post-operative Dosing


Pre-op dosing

(beginning at diagnosis)

 Pre-incisional dosing  Intra-op re-dosing interval
(max: 875 mg Amoxicillin/dose)
 N/A  N/A  N/A  N/A 22.5 mg/kg/dose Amoxicillin component PO q12hrs 
(max: 2 g/dose)
 N/A  40 mg/kg/dose
IV x1 within 60 minutes prior to incision, unless Ceftriaxone given within prior 8 hrs
 q2hrs  N/A  N/A


(max: 2 g/dose)


 50 mg/kg/dose IV q24hrs  N/A  N/A

 50mg/kg IV x 1 dose given 24 hrs after prior dose

(may administer post-op dose early to facilitate discharge if >=8 hrs since prior dose)

 50 mg/kg/dose IV q24hrs

(max IV: 400 mg/dose)

(max PO: 500 mg/dose)


15 mg/kg/dose IV q12hrs


15mg/kg/dose IV x 1 within 120 minutes prior to incision, if >=12 hours from prior dose


15 mg/kg/dose IV q12hrs x 2 doses starting 12 hrs after prior dose

 15 mg/kg/dose IV q12hrs


15mg/kg/dose PO BID


(max q24 IV: 1.5 g/dose)

(max PO: 500 mg/dose)

 30 mg/kg/dose IV q24hrs  N/A  N/A  

30 mg/kg/dose IV x 1 dose given 24 hrs after prior dose

 30 mg/kg/dose IV q24hrs


10 mg/kg/dose PO TID

Piperacillin/tazobactam (Zosyn)
(max: 4 g Piperacillin/dose)
 N/A  N/A  N/A  N/A  

80mg/kg/dose Piperacillin component IV q6hrs



Initiated 2019. Content development led by Pediatric Antimicrobial Stewardship Program at BCH Oakland with collaboration by Pediatric Antimicrobial Stewardship Program at BCHSF, Pediatric Surgery and Pediatric Emergency Medicine programs at BCHO and BCHSF. 

Approved by UCSF Committee on Pharmacy and Therapeutics 5/14/19. Please direct questions about SF algorithm content to [email protected]


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