Infants and Children: Very limited data available: Intraventricular/Intrathecal: Colistin base: Reported range: 1 to 4.2 mg CBA/dose once daily in combination with systemic antibiotics (Dalgic 2009; IDSA [Tunkel 2017]; Ng 2006; Ozdemir 2010). Doses should be individualized based on culture/sensitivity, MIC, and tolerability while ensuring that patient size and CSF volume are considered. In one case report, a 4-year old with multidrug resistant Acinetobacter baumannii received an intraventricular dose of 1 mg CBA on Day 1, followed by 2 mg CBA once daily for 2 days, then 4 mg CBA once daily; after 13 days, a dose reduction to 2 mg CBA once daily was necessary due to CSF leukocytosis (Ng 2006). A similar protocol was described in a 2-month old with multidrug resistant Acinetobacter baumannii; the initial dose on Day 1 was 1 mg CBA followed by 2 mg CBA once daily for 2 days, then 4 mg CBA once daily; due to failure to sterilize the CSF, the dose was slowly titrated up to 10 mg CBA/day for a total of 20 days (Dalgic 2009). In a case report of a 3-year old with multidrug resistant Acinetobacter baumannii, intrathecal colistin was administered without titration at a dose of 4.2 mg CBA/day (Ozdemir 2010).

Adolescents: Very limited data available: Intraventricular/Intrathecal: Colistin base: 4.2 mg CBA/day (equivalent to 10 mg CMS/day) (IDSA [Tunkel 2017]; Yagmur 2006); Note: Dose in clinical reports in adults has ranged from 0.7 to 8.3 mg CBA/day in 1 or 2 divided doses (administered with concomitant systemic antimicrobial therapy) (Benifla 2004; Falagas 2007; Imberti 2012; Katragkou 2005)