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Dosage and Administration

Administration

Oral Administration

Administer orally without regard to meals.

Following reconstitution, the required amount of oral suspension should be placed directly on the child’s tongue for swallowing. Alternatively, the required amount of suspension can be added to infant formula, milk, fruit juice, water, ginger ale, or cold drinks and these fluids taken immediately and completely consumed.

For most infections, continue therapy for at least 48–72 hours after patient becomes asymptomatic or evidence that the infection is eradicated is obtained. The drug should be given for at least 10 days for treatment of infections caused by S. pyogenes (group A β-hemolytic streptococci).

Reconstitution

Reconstitute oral suspension at the time of dispensing. Tap bottle to thoroughly loosen powder and then add the amount of water specified on the bottle in 2 portions; agitate vigorously after each addition.

Agitate suspension well prior to administration of each dose.

Dosage

Available as the trihydrate; dosage expressed in terms of anhydrous amoxicillin.

Pediatric Patients

Neonates and infants ≤12 weeks (3 months) of age can receive amoxicillin in a dosage up to 30 mg/kg daily given in divided doses every 12 hours.

Pediatric dosage specified below is for those >3 months of age weighing <40 kg.

Children weighing ≥40 kg should receive usual adult dosage.

Otitis Media

Treatment of Acute Otitis Media (AOM)

Oral

80–90 mg/kg daily given in 2 or 3 divided doses† recommended by AAP, AAFP, CDC, and others.

Usual duration is 10 days; optimal duration is uncertain. AAP and AAFP recommend 10 days in those <6 years of age and in those with severe disease and state 5–7 days may be appropriate in those ≥6 years of age with mild to moderate AOM.

Prevention of Recurrent AOM

Oral

20 mg/kg daily given in 1 or 2 divided doses has been used.†

Pharyngitis and Tonsillitis

Oral

45 mg/kg daily in 2 divided doses or 40 mg/kg daily in 3 divided doses for 10 days.

50 mg/kg once daily or 750 mg once daily for 10 days†.

Follow-up throat cultures after treatment of pharyngitis and tonsillitis not indicated in asymptomatic patients, but recommended 2–7 days after treatment in those who remain symptomatic, develop recurring symptoms, or have a history of rheumatic fever and are at unusually high risk for recurrence.

Ear, Nose, and Throat Infections

Oral

25 mg/kg daily in divided doses every 12 hours or 20 mg/kg daily in divided doses every 8 hours for mild to moderate infections per manufacturer.

45 mg/kg daily in divided doses every 12 hours or 40 mg/kg in divided doses every 8 hours for severe infections per manufacturer.

Respiratory Tract Infections

Oral

45 mg/kg daily in divided doses every 12 hours or 40 mg/kg daily in divided doses every 8 hours for mild, moderate, or severe lower respiratory tract infections.

Skin and Skin Structure Infections

Oral

25 mg/kg daily in divided doses every 12 hours or 20 mg/kg daily in divided doses every 8 hours for mild to moderate infections.

45 mg/kg daily in divided doses every 12 hours or 40 mg/kg daily in divided doses every 8 hours for severe infections or those caused by less susceptible bacteria.

Urinary Tract Infections (UTIs)

Oral

25 mg/kg daily in divided doses every 12 hours or 20 mg/kg daily in divided doses every 8 hours for mild to moderate infections.

45 mg/kg daily in divided doses every 12 hours or 40 mg/kg daily in divided doses every 8 hours for severe infections or those caused by less susceptible bacteria.

Gonorrhea

Oral

Prepubertal children ≥2 years of age: 50 mg/kg as a single dose given with a single dose of probenecid (25 mg/kg).

No longer recommended for gonorrhea by the CDC or other experts.

Lyme Disease

Oral

25–50 mg/kg daily (up to 2 g daily) in 2–3 divided doses for 14–21 days for treatment of early localized or early disseminated Lyme disease†.

50 mg/kg daily in 3 divided doses for 14–28 days for mild Lyme carditis or for 28 days for Lyme arthritis (without associated neurologic disease).

Prevention of Bacterial Endocarditis

Patients Undergoing Certain Dental, Oral, Respiratory Tract, or Esophageal Procedures

Oral

50 mg/kg given 1 hour prior to the procedure.

Patients Undergoing Certain GU or GI (except Esophageal) Procedures

Oral

50 mg/kg as a single dose given 1 hour prior to the procedure for moderate-risk patients.

For high-risk patients, give an initial IM or IV dose of ampicillin with IM or IV gentamicin within 30 minutes of starting the procedure followed by 25 mg/kg of amoxicillin 6 hours later.

Prevention of S. pneumoniae Infections in Asplenic Individuals

Oral

20 mg/kg daily in children with anatomic or functional asplenia.†

In infants with sickle cell anemia, initiate prophylaxis as soon as diagnosis is established (preferably by 2 months of age); continue until approximately 5 years of age. Appropriate duration in children with asplenia from other causes unknown; some experts recommend that asplenic children at high risk receive prophylaxis throughout childhood and into adulthood.†

Anthrax

Postexposure Prophylaxis

Oral

80 mg/kg daily (maximum 1.5 g daily) given in divided doses every 8 hours for 60 days for postexposure prophylaxis following exposure to B. anthracis spores (inhalational anthrax)†.

500 mg every 8 hours for 60 days in those weighing ≥20 kg.

Use only if penicillin susceptibility is confirmed.

Inhalational Anthrax

Oral

80 mg/kg daily (maximum 1.5 g daily) given in divided doses every 8 hours for 60 days for treatment of inhalational anthrax in a mass-casualty setting†.

500 mg every 8 hours for 60 days for those weighing ≥20 kg.

Cutaneous Anthrax

Oral

80 mg/kg daily (maximum 1.5 g daily) given in divided doses every 8 hours for treatment of uncomplicated cutaneous anthrax†.

Treat for 60 days if cutaneous anthrax occurred as the result of exposure to aerosolized anthrax spores; 7–10 days may be adequate if it occurred as the result of natural or endemic exposure to anthrax.

Adults

Pharyngitis and Tonsillitis

Oral

500 mg 3 times daily or 750 mg once daily† for 10 days.

Follow-up throat cultures after treatment of pharyngitis and tonsillitis not indicated in asymptomatic patients, but recommended 2–7 days after treatment in those who remain symptomatic, develop recurring symptoms, or have a history of rheumatic fever and are at unusually high risk for recurrence.

Ear, Nose, and Throat Infections

Oral

500 mg every 12 hours or 250 mg every 8 hours for mild to moderate infections per manufacturer.

875 mg every 12 hours or 500 mg every 8 hours for severe infections or those caused by less susceptible bacteria per manufacturer.

Respiratory Tract Infections

Oral

875 mg every 12 hours or 500 mg every 8 hours for mild, moderate, or severe lower respiratory tract infections.

Skin and Skin Structure Infections

Oral

500 mg every 12 hours or 250 mg every 8 hours for mild to moderate infections.

875 mg every 12 hours or 500 mg every 8 hours for severe infections or those caused by less susceptible bacteria.

Urinary Tract Infections (UTIs)

Oral

500 mg every 12 hours or 250 mg every 8 hours for mild to moderate infections.

875 mg every 12 hours or 500 mg every 8 hours for severe infections or those caused by less susceptible bacteria.

Gonorrhea

Oral

3 g as a single dose.

No longer recommended for gonorrhea by the CDC or other experts.

Typhoid Fever

Oral

100 mg/kg daily or 1–1.5 g every 6 hours for 14 days.

Helicobacter pylori Infection and Duodenal Ulcer Disease

Oral

1 g 2 times daily for 10 or 14 days given in conjunction with clarithromycin and either lansoprazole or omeprazole (triple therapy).

1 g 3 times daily for 14 days given in conjunction with lansoprazole (dual therapy).

Lyme Disease

Oral

500 mg 3 times daily for 14–21 days for treatment of early localized or early disseminated Lyme disease†.

500 mg 3 times daily for 14–28 days for mild Lyme carditis or for 28 days for Lyme arthritis (without associated neurologic disease).

Chlamydial Infections

Oral

500 mg 3 times daily for 7 days for treatment of chlamydial infections in pregnant women†.

Repeat testing (preferably by culture) recommended 3 weeks after completion of treatment.

Prevention of Bacterial Endocarditis

Patients Undergoing Certain Dental, Oral, Respiratory Tract, or Esophageal Procedures

Oral

2 g given 1 hour prior to the procedure.

Patients Undergoing Certain GU or GI (except Esophageal) Procedures

Oral

2 g given 1 hour prior to the procedure in moderate-risk patients.

For high-risk patients, give an initial IM or IV dose of ampicillin with IM or IV gentamicin within 30 minutes of starting the procedure followed by 1 g of amoxicillin 6 hours later.

Anthrax

Postexposure Prophylaxis

Oral

500 mg every 8 hours for 60 days for postexposure prophylaxis following exposure to B. anthracis spores†; use only if penicillin susceptibility confirmed.

Inhalational Anthrax

Oral

500 mg every 8 hours for 60 days for treatment of inhalational anthrax†.

Cutaneous Anthrax

Oral

500 mg every 8 hours for treatment of inhalational anthrax†.

Treat for 60 days if cutaneous anthrax occurred as the result of exposure to aerosolized anthrax spores; 7–10 days may be adequate if it occurred as the result of natural or endemic exposure to anthrax.

Prescribing Limits

Pediatric Patients

Neonates and Infants ≤12 weeks (3 Months) of Age

Oral

Maximum 30 mg/kg daily in divided doses every 12 hours.

Prevention of Bacterial Endocarditis

Oral

Dosage should not exceed adult dosage for prevention of bacterial endocarditis.

Special Populations

Dosage in Renal Impairment

Dosage adjustment necessary in severe renal impairment.

Do not use 875-mg tablets in those with severe renal impairment and GFR <30 mL/minute.

Dosage recommendations not available for pediatric patients with renal impairment.