Adult and pediatric3 20kg
Usual dose:

IM/IV, 250-500 mg q6h. Max. 14 g/d
Endocarditis;Meningitis;Septicemia: IM/IV, 1-2 g q 3-4h.
Listeriosis: IM/IV, 50 mg/kg q6h.
Pediatric
Antibacterial:
Infants and children< 20kg:IM/IV, 12.5 mg/kg q6h.
Meningitis:
Neonates< 2 kg: IM/IV, 25-50 mg/kg q12h during the 1st wk of life then 50 mg/kg q8h thereafter.

M: GI disturbances; headache; oral or vaginal candidiasis
L: Allergic reactions; exfoliative dermatitis; serum sickness–like reactions; skin rash or itching
R: Clostridium difficile colitis; hepatotoxicity; interstitial nephritis; leukopenia or neutropenia; mental disturbances; pain at site of injection; platelet dysfunction or thrombocytopenia; seizures