Antibiotic	Typical dosage*	Maximum dosage
Oral administration
Amoxicillin†	25 to 50 mg per kg per day, divided into 3 doses	500 mg per dose
	Prophylactic dosage: 10 to 15 mg per kg once per day
Amoxicillin/clavulanate (Augmentin)	Children 2 to 24 months of age: 20 to 40 mg amoxicillin per kg per day, divided into 3 doses	—
Cefixime (Suprax)	Children 2 months and older: 8 mg per kg once per day	400 mg per dose
Cefuroxime axetil	Children older than 2 months: 20 to 30 mg per kg per day, divided into 2 doses	500 mg per dose
Cephalexin (Keflex)‡	Children 2 to 24 months of age: 50 to 100 mg per kg per day, divided into 4 doses	500 mg per dose
	Children older than 24 months: 25 to 50 mg per kg per day, divided into 2 to 4 doses; for severe infections, 50 to 100 mg per kg per day, divided into 2 to 4 doses
Nitrofurantoin§	5 to 7 mg per kg per day, divided into 4 doses	100 mg per dose
	Prophylactic dosage: 1 to 2 mg per kg at bedtime
Trimethoprim/sulfamethoxazole†	Children 2 to 24 months of age: 6 mg/30 mg to 12 mg/60 mg per kg per day, divided into 2 doses	160 mg trimethoprim per dose
	Children older than 24 months: 8 mg/40 mg per kg per day, divided into 2 doses Prophylactic dosage for children 2 months and older: 2 mg/10 mg per kg once per day
Intravenous administration
Ampicillin	50 to 400 mg per kg per day, divided into 4 doses	12,000 mg per day
Cefazolin‡	25 to 100 mg per kg per day, divided into 3 doses	6,000 mg per day
Cefepime	Children 2 months and older: 100 mg per kg per day, divided into 2 doses	2,000 mg per dose
Cefotaxime	Children 2 to 24 months of age: 150 mg per kg per day, divided into 3 or 4 doses	—
Ceftriaxone	50 mg per kg once per day	2,000 mg per dose
Gentamicin||	Extended-interval dosing:	—
	Neonates 7 days or younger: 4 mg per kg per day
	Neonates/infants 8 to 60 days of age: 5 mg per kg per day
	Infants/children 2 months to 5 years of age: 7.5 mg per kg once per day
	Conventional dosing:
	7.5 mg per kg per day, divided into 3 doses