Patient age	Outpatient		Inpatient			Critically ill
Birth to 20 days	Admit		Ampicillin IV or IM: Age>7 days: Weight <2 kg (4.4 lb): 50 to 100 mg per kg per day in divided doses every 12 hours Weight ≥2 kg: 75 to 150 mg per kg per day in divided doses every 8 hours Age ≥7 days: Weight <1.2 kg (2.6 lb): 50 to 100 mg per kg per day divided every 12 hours Weight 1.2 to 2 kg: 75 to 150 mg per kg per day in divided doses every 8 hours Weight >2 kg: 100 to 200 mg per kg per day in divided doses every 6 hours plus Gentamicin IV or IM: ≥37 weeks of gestation and Age zero to 7 days: 2.5 mg per kg every 12 hours Age >7 days: 2.5 mg per kg every 8 hours with or without Cefotaxime (Claforan) IV: Age ≤7 days: 100 mg per kg per day in divided doses every 12 hours Age >7 days: 150 mg per kg per day in divided doses every 8 hours			Ampicillin IV or IM, in same dosages as for inpatients plus Gentamicin IV or IM, with or without cefotaxime IV, in same dosages as for inpatients
3 weeks to 3 months	If patient is afebrile: Azithromycin (Zithromax), 10 mg per kg orally on day 1, then 5 mg per kg per day on days 2 through 5 or Erythromycin, 30 to 40 mg per kg per day orally in divided doses every 6 hours for 10 days Admit if patient is febrile or hypoxic.		Erythromycin, 40 mg per kg per day IV in divided doses every 6 hours* If patient is febrile, add one of these agents: Cefotaxime, 200 mg per kg per day IV in divided doses every 8 hours* or Cefuroxime (Ceftin), 150 mg per kg per day IV in divided doses every 8 hours*			Cefotaxime, 200 mg per kg per day IV in divided doses every 8 hours plus cloxacillin (Tegopen), 150 to 200 mg per kg per day IV in divided doses every 6 hours* or Cefuroxime alone, 150 mg per kg per day IV in divided doses every 8 hours*
4 months to 5 years	Amoxicillin, 90 mg per kg per day orally in divided doses every 8 hours for 7 to 10 days Consider initial dose of ceftriaxone (Rocephin), 50 mg per kg per day IM, up to 1 g per day. Follow with oral therapy for full course. Alternatives: amoxicillin- clavulanic acid (Augmentin), azithromycin, cefaclor (Ceclor), clarithromycin (Biaxin), erythromycin		Cefotaxime, 150 mg per kg per day IV in divided doses every 6 hours* Cefuroxime, 150 mg per kg per day IV in divided doses every 8 hours*or If the patient has pneumococcal infection: Ampicillin alone, 200 mg per kg per day IV in divided doses every 8 hours*			Cefuroxime, 150 mg per kg per day IV in divided doses every 8 hours, plus erythromycin, 40 mg per kg per day IV or orally in divided doses every 6 hours for 10 to 14 days* or Cefotaxime, 200 mg per kg per day IV in divided doses every 8 hours, plus cloxacillin, 150 to 200 mg per kg per day IV in divided doses every 6 hours for 10 to 14 days
5 years and older	Azithromycin, 10 mg per kg (maximum of 500 mg) orally on day 1, followed by 5 mg per kg per day on days 2 through 5 or Clarithromycin, 15 mg per kg per day orally in divided doses every 12 hours for 7 to 10 days  or Erythromycin, 40 mg per kg per day orally in divided doses every 6 hours for 7 to 10 days If the patient has pneumococcal infection: Amoxicillin alone, 90 mg per kg per day orally in divided doses every 8 hours		Cefuroxime, 150 mg per kg per day IV in divided doses every 8 hours plus Erythromycin, 40 mg per kg per day IV or orally in divided doses every 6 hours for 10 to 14 days If pneumococcal infection is confirmed: Ampicillin alone, 200 mg per kg per day IV in divided doses every 8 hours			Cefuroxime, 150 mg per kg per day IV in divided doses every 8 hours plus Erythromycin, 40 mg per kg per day IV or orally in divided doses every 6 hours for 10 to 14 days