Ampicillin Dosage

Medically reviewed by Drugs.com. Last updated on Aug 3, 2023.

Usual Adult Dose for Endocarditis

The manufacturer gives no specific dosing instructions.

Comments:

• Endocarditis due to enterococcal strains generally responds to IV therapy.
• Use with an aminoglycoside may enhance efficacy when treating streptococcal endocarditis.

Use (parenteral): For the treatment of endocarditis due to susceptible gram-positive organisms including Streptococcus species, penicillin G-susceptible staphylococci, and enterococci

American Heart Association (AHA) and Infectious Diseases Society of America (IDSA) Recommendations: 2 g IV every 4 hours

Duration of Therapy:

• Native valve infective endocarditis (NVE) due to highly penicillin-susceptible viridans group streptococci (VGS) or Streptococcus gallolyticus (bovis): 4 weeks
• NVE due to relatively penicillin-resistant strains of VGS or S gallolyticus (bovis): 4 weeks
• Prosthetic valve (or other prosthetic material) infection due to VGS or S gallolyticus (bovis): 6 weeks
• NVE or prosthetic valve (or other prosthetic material) infection due to Enterococcus species by a strain susceptible to penicillin and gentamicin (if able to tolerate beta-lactam therapy): 4 to 6 weeks (with gentamicin); 6 weeks (with ceftriaxone)
• NVE or prosthetic valve (or other prosthetic material) infection due to Enterococcus species by a strain susceptible to penicillin and resistant to aminoglycosides or streptomycin-susceptible gentamicin-resistant (if able to tolerate beta-lactam therapy): 6 weeks (with ceftriaxone); 4 to 6 weeks (with streptomycin)
• NVE or prosthetic valve (or other prosthetic material) infection due to HACEK microorganisms: 4 weeks (NVE); 6 weeks (prosthetic valve infection)

Comments:

• Recommended for patients with normal renal function
• Recommended as an alternative to penicillin (if penicillin shortage):
• For NVE due to highly penicillin-susceptible VGS and S gallolyticus (bovis)
• With gentamicin, for NVE due to relatively penicillin-resistant strains of VGS or S gallolyticus (bovis)
• With or without gentamicin (penicillin-susceptible strain [MIC up to 0.12 mcg/mL]) or with gentamicin (relatively/fully penicillin-resistant strain [MIC greater than 0.12 mcg/mL]), for prosthetic valve (or other prosthetic material) infection due to VGS or S gallolyticus (bovis)
• With gentamicin or ceftriaxone, recommended for NVE or prosthetic valve (or other prosthetic material) infection due to Enterococcus species by a strain susceptible to penicillin and gentamicin (if able to tolerate beta-lactam therapy)
• With ceftriaxone or streptomycin, recommended for NVE or prosthetic valve (or other prosthetic material) infection due to Enterococcus species by a strain susceptible to penicillin and resistant to aminoglycosides or streptomycin-susceptible gentamicin-resistant (if able to tolerate beta-lactam therapy)
• Recommended for NVE or prosthetic valve (or other prosthetic material) infection due to HACEK microorganisms (if isolate growth adequate to permit in vitro susceptibility results)
• HACEK indicates Haemophilus species, Aggregatibacter species, Cardiobacterium hominis, Eikenella corrodens, and Kingella species
• Current guidelines should be consulted for additional information.

Usual Adult Dose for Meningitis

Parenteral: 150 to 200 mg/kg/day IV in equally divided doses every 3 to 4 hours
Oral: The manufacturer gives no specific dosing instructions.

Comments:

• Therapy may be started with IV administration and continued with IM injections.
• Use with an aminoglycoside may increase efficacy against gram-negative bacteria.

Uses:

• Parenteral: For the treatment of bacterial meningitis due to Escherichia coli, group B streptococci, and other gram-negative bacteria (Neisseria meningitidis)
• Oral: For the treatment of meningitis due to N meningitidis

IDSA Recommendations: 12 g/day IV in divided doses every 4 hours

Duration of Therapy:

• Aerobic gram-negative bacilli: 21 days
• Haemophilus influenzae: 7 days
• L monocytogenes: At least 21 days
• N meningitidis: 7 days
• S agalactiae: 14 to 21 days
• S pneumoniae: 10 to 14 days

Comments:

• Based on presumptive pathogen identification by positive Gram stain: A recommended agent for infection due to L monocytogenes or S agalactiae (use with an aminoglycoside should be considered); recommended as an alternative agent for infection due to N meningitidis
• Based on isolated pathogen and susceptibility testing: Considered standard therapy for S pneumoniae or N meningitidis infection with penicillin MIC less than 0.1 mcg/mL, beta-lactamase negative H influenzae, and (with gentamicin) ampicillin-susceptible Enterococcus species; recommended as alternative therapy for infection due to E coli and other Enterobacteriaceae
• Current guidelines should be consulted for additional information.

Usual Adult Dose for Septicemia

150 to 200 mg/kg/day IV

Comments:

• Start with IV administration for at least 3 days and continue with the IM route every 3 to 4 hours

Uses: For the treatment of septicemia due to susceptible gram-positive organisms including Streptococcus species, penicillin G-susceptible staphylococci, and enterococci; for the treatment of gram-negative sepsis due to E coli, Proteus mirabilis, and Salmonella species

Usual Adult Dose for Intraabdominal Infection

500 mg orally or IM or IV every 6 hours

Comments:

• Parenteral: For patients weighing at least 40 kg
• Oral: For patients weighing at least 20 kg
• Frequent bacteriological and clinical assessment needed during therapy (and may be needed for several months afterwards) when treating chronic urinary tract and intestinal infections.
• Severe, chronic, or stubborn infections may require larger doses.

Uses:

• Parenteral: For the treatment of gastrointestinal infections due to Salmonella species (including Salmonella typhi) and Shigella species; for the treatment of urinary tract infections due to sensitive strains of E coli and P mirabilis
• Oral: For the treatment of gastrointestinal tract infections due to Shigella, Salmonella species (including S typhi), E coli, P mirabilis, and enterococci; for the treatment of genitourinary tract infections due to E coli, P mirabilis, enterococci, Shigella, Salmonella species (including S typhi)

Usual Adult Dose for Shigellosis

500 mg orally or IM or IV every 6 hours

Comments:

• Parenteral: For patients weighing at least 40 kg
• Oral: For patients weighing at least 20 kg
• Frequent bacteriological and clinical assessment needed during therapy (and may be needed for several months afterwards) when treating chronic urinary tract and intestinal infections.
• Severe, chronic, or stubborn infections may require larger doses.

Uses:

• Parenteral: For the treatment of gastrointestinal infections due to Salmonella species (including Salmonella typhi) and Shigella species; for the treatment of urinary tract infections due to sensitive strains of E coli and P mirabilis
• Oral: For the treatment of gastrointestinal tract infections due to Shigella, Salmonella species (including S typhi), E coli, P mirabilis, and enterococci; for the treatment of genitourinary tract infections due to E coli, P mirabilis, enterococci, Shigella, Salmonella species (including S typhi)

Usual Adult Dose for Urinary Tract Infection

500 mg orally or IM or IV every 6 hours

Comments:

• Parenteral: For patients weighing at least 40 kg
• Oral: For patients weighing at least 20 kg
• Frequent bacteriological and clinical assessment needed during therapy (and may be needed for several months afterwards) when treating chronic urinary tract and intestinal infections.
• Severe, chronic, or stubborn infections may require larger doses.

Uses:

• Parenteral: For the treatment of gastrointestinal infections due to Salmonella species (including Salmonella typhi) and Shigella species; for the treatment of urinary tract infections due to sensitive strains of E coli and P mirabilis
• Oral: For the treatment of gastrointestinal tract infections due to Shigella, Salmonella species (including S typhi), E coli, P mirabilis, and enterococci; for the treatment of genitourinary tract infections due to E coli, P mirabilis, enterococci, Shigella, Salmonella species (including S typhi)

Usual Adult Dose for Typhoid Fever

500 mg orally or IM or IV every 6 hours

Comments:

• Parenteral: For patients weighing at least 40 kg
• Oral: For patients weighing at least 20 kg
• Frequent bacteriological and clinical assessment needed during therapy (and may be needed for several months afterwards) when treating chronic urinary tract and intestinal infections.
• Severe, chronic, or stubborn infections may require larger doses.

Uses:

• Parenteral: For the treatment of gastrointestinal infections due to Salmonella species (including Salmonella typhi) and Shigella species; for the treatment of urinary tract infections due to sensitive strains of E coli and P mirabilis
• Oral: For the treatment of gastrointestinal tract infections due to Shigella, Salmonella species (including S typhi), E coli, P mirabilis, and enterococci; for the treatment of genitourinary tract infections due to E coli, P mirabilis, enterococci, Shigella, Salmonella species (including S typhi)

Usual Adult Dose for Gastroenteritis

500 mg orally or IM or IV every 6 hours

Comments:

• Parenteral: For patients weighing at least 40 kg
• Oral: For patients weighing at least 20 kg
• Frequent bacteriological and clinical assessment needed during therapy (and may be needed for several months afterwards) when treating chronic urinary tract and intestinal infections.
• Severe, chronic, or stubborn infections may require larger doses.

Uses:

• Parenteral: For the treatment of gastrointestinal infections due to Salmonella species (including Salmonella typhi) and Shigella species; for the treatment of urinary tract infections due to sensitive strains of E coli and P mirabilis
• Oral: For the treatment of gastrointestinal tract infections due to Shigella, Salmonella species (including S typhi), E coli, P mirabilis, and enterococci; for the treatment of genitourinary tract infections due to E coli, P mirabilis, enterococci, Shigella, Salmonella species (including S typhi)

Usual Adult Dose for Skin or Soft Tissue Infection

250 to 500 mg IM or IV every 6 hours

Comments:

• For patients weighing at least 40 kg

Use: For the treatment of soft tissue infections

Usual Adult Dose for Pharyngitis

Parenteral: 250 to 500 mg IM or IV every 6 hours
Oral: 250 mg orally every 6 hours

Comments:

• Parenteral: For patients weighing at least 40 kg
• Oral: For patients weighing at least 20 kg

Uses:

• Parenteral: For the treatment of respiratory tract infections due to S pneumoniae, Staphylococcus aureus (penicillinase and non-penicillinase producing), H influenzae, and group A beta-hemolytic streptococci
• Oral: For the treatment of respiratory tract infections due to non-penicillinase-producing H influenzae and staphylococci, and streptococci (including S pneumoniae)

Usual Adult Dose for Pneumonia

Parenteral: 250 to 500 mg IM or IV every 6 hours
Oral: 250 mg orally every 6 hours

Comments:

• Parenteral: For patients weighing at least 40 kg
• Oral: For patients weighing at least 20 kg

Uses:

• Parenteral: For the treatment of respiratory tract infections due to S pneumoniae, Staphylococcus aureus (penicillinase and non-penicillinase producing), H influenzae, and group A beta-hemolytic streptococci
• Oral: For the treatment of respiratory tract infections due to non-penicillinase-producing H influenzae and staphylococci, and streptococci (including S pneumoniae)

Usual Adult Dose for Sinusitis

Parenteral: 250 to 500 mg IM or IV every 6 hours
Oral: 250 mg orally every 6 hours

Comments:

• Parenteral: For patients weighing at least 40 kg
• Oral: For patients weighing at least 20 kg

Uses:

• Parenteral: For the treatment of respiratory tract infections due to S pneumoniae, Staphylococcus aureus (penicillinase and non-penicillinase producing), H influenzae, and group A beta-hemolytic streptococci
• Oral: For the treatment of respiratory tract infections due to non-penicillinase-producing H influenzae and staphylococci, and streptococci (including S pneumoniae)

Usual Adult Dose for Upper Respiratory Tract Infection

Parenteral: 250 to 500 mg IM or IV every 6 hours
Oral: 250 mg orally every 6 hours

Comments:

• Parenteral: For patients weighing at least 40 kg
• Oral: For patients weighing at least 20 kg

Uses:

• Parenteral: For the treatment of respiratory tract infections due to S pneumoniae, Staphylococcus aureus (penicillinase and non-penicillinase producing), H influenzae, and group A beta-hemolytic streptococci
• Oral: For the treatment of respiratory tract infections due to non-penicillinase-producing H influenzae and staphylococci, and streptococci (including S pneumoniae)

Usual Adult Dose for Bronchitis

Parenteral: 250 to 500 mg IM or IV every 6 hours
Oral: 250 mg orally every 6 hours

Comments:

• Parenteral: For patients weighing at least 40 kg
• Oral: For patients weighing at least 20 kg

Uses:

• Parenteral: For the treatment of respiratory tract infections due to S pneumoniae, Staphylococcus aureus (penicillinase and non-penicillinase producing), H influenzae, and group A beta-hemolytic streptococci
• Oral: For the treatment of respiratory tract infections due to non-penicillinase-producing H influenzae and staphylococci, and streptococci (including S pneumoniae)

Usual Adult Dose for Bacterial Endocarditis Prophylaxis

AHA Recommendations: 2 g IM or IV as a single dose 30 to 60 minutes before procedure

Comments:

• Recommended for patients unable to take oral medication
• Antibiotic prophylaxis may be used for dental procedures (involving manipulation of gingival tissues or periapical region of teeth or perforation of oral mucosa), respiratory tract procedures, or procedures on infected skin, skin structures, or musculoskeletal tissue only for patients with the highest risk of infective endocarditis.
• Current guidelines should be consulted for additional information.

Usual Adult Dose for Prevention of Perinatal Group B Streptococcal Disease

US CDC Recommendations:

• For latency: 2 g IV once, followed by 1 g IV every 6 hours for at least 48 hours
• Group B Streptococcus (GBS) prophylaxis: 2 g IV initial dose, then 1 g IV every 4 hours until delivery

Comments:

• Recommended as a regimen to prolong latency for preterm premature rupture of membranes; adequate for GBS prophylaxis if delivery occurs while using this regimen
• Recommended as an alternative regimen for intrapartum antibiotic prophylaxis for prevention of early-onset GBS disease
• Current guidelines should be consulted for additional information.

Usual Adult Dose for Surgical Prophylaxis

American Society of Health-System Pharmacists (ASHP), IDSA, Surgical Infection Society (SIS), and Society for Healthcare Epidemiology of America (SHEA) Recommendations: 2 g IV as a single dose

Redosing interval (from start of preoperative dose): 2 hours

Comments:

• With cefotaxime, a recommended regimen for surgical prophylaxis in patients undergoing liver transplantation
• This drug should be started within 60 minutes before surgical incision.
• A single prophylactic dose is usually sufficient; if prophylaxis is continued postoperatively, duration should be less than 24 hours.
• To ensure adequate serum and tissue drug levels, readministration may be needed if the procedure duration exceeds the recommended redosing interval.
• Redosing may be needed if drug half-life is shortened (e.g., extensive burns) or if prolonged/excessive bleeding during surgery; redosing may not be needed if drug half-life is prolonged (e.g., renal dysfunction).
• Current guidelines should be consulted for additional information.

Usual Adult Dose for Peritonitis

International Society for Peritoneal Dialysis (ISPD) Recommendations:
Continuous (all exchanges):

• Maintenance dose: 125 mg/L intraperitoneally

Duration of Therapy: 14 to 21 days

Comments:

• Recommended for the treatment of peritoneal dialysis (PD)-related peritonitis
• Current guidelines should be consulted for additional information.

Usual Adult Dose for Inhalation Bacillus anthracis

US CDC Recommendations: 3 g IV every 6 hours

Duration of Therapy:

• With possible/confirmed meningitis: At least 2 to 3 weeks or until patient is clinically stable (whichever is longer)
• When meningitis has been excluded: At least 2 weeks or until patient is clinically stable (whichever is longer)

Comments:

• Recommended as an alternative agent for the treatment of systemic anthrax due to penicillin-susceptible strains
• Recommended for use with a protein synthesis inhibitor; the addition of a bactericidal fluoroquinolone is recommended with possible/confirmed meningitis.
• Systemic anthrax includes anthrax meningitis, inhalation anthrax, injection anthrax, gastrointestinal anthrax, and cutaneous anthrax with systemic involvement, extensive edema, or lesions of the head or neck.
• Patients exposed to aerosolized spores will require prophylaxis to complete an antimicrobial regimen of 60 days from onset of illness.
• Current guidelines should be consulted for additional information.

Usual Adult Dose for Cutaneous Bacillus anthracis

US CDC Recommendations: 3 g IV every 6 hours

Duration of Therapy:

• With possible/confirmed meningitis: At least 2 to 3 weeks or until patient is clinically stable (whichever is longer)
• When meningitis has been excluded: At least 2 weeks or until patient is clinically stable (whichever is longer)

Comments:

• Recommended as an alternative agent for the treatment of systemic anthrax due to penicillin-susceptible strains
• Recommended for use with a protein synthesis inhibitor; the addition of a bactericidal fluoroquinolone is recommended with possible/confirmed meningitis.
• Systemic anthrax includes anthrax meningitis, inhalation anthrax, injection anthrax, gastrointestinal anthrax, and cutaneous anthrax with systemic involvement, extensive edema, or lesions of the head or neck.
• Patients exposed to aerosolized spores will require prophylaxis to complete an antimicrobial regimen of 60 days from onset of illness.
• Current guidelines should be consulted for additional information.

Usual Adult Dose for Gonococcal Infection - Uncomplicated

Parenteral:

• Genitourinary tract infections due to N gonorrhoeae in females: 500 mg IM or IV every 6 hours
• Urethritis due to N gonorrhoeae in males: 500 mg IM or IV every 8 to 12 hours for 2 doses

Oral:

• Gonorrhea: 3.5 g orally as a single dose (plus probenecid 1 g)

Comments:

• Due to resistance, penicillins are not recommended by the US CDC; current guidelines should be consulted for additional information.
• Parenteral: For patients weighing at least 40 kg
• Oral: For patients weighing at least 20 kg
• No less than the above recommended dose should be used to treat gonorrhea.
• Follow-up cultures from original infection site recommended 7 to 14 days after therapy; in women, culture test-of-cure should be obtained from both the endocervical and anal canals.
• Urethritis treatment may be repeated or extended if necessary.
• Prolonged intensive therapy is needed for complications of gonorrheal urethritis (such as prostatitis and epididymitis).

Uses:

• Parenteral: For the treatment of genitourinary tract infections (including those due to N gonorrhoeae in females); for the treatment of urethritis due to N gonorrhoeae in males
• Oral: For the treatment of genitourinary tract infections (including gonorrhea) due to non-penicillinase-producing N gonorrhoeae

Usual Pediatric Dose for Bacterial Infection

American Academy of Pediatrics (AAP) Recommendations:
Neonates:

• Gestational age up to 34 weeks:
• Postnatal age up to 7 days: 50 mg/kg IM or IV every 12 hours
• Postnatal age 8 to 28 days: 75 mg/kg IM or IV every 12 hours
• Gestational age greater than 34 weeks:
• Postnatal age up to 28 days: 50 mg/kg IM or IV every 8 hours

1 month or older:

• Parenteral: 50 to 200 mg/kg/day IM or IV divided in 4 doses
• Maximum dose: 8 g/day
• Oral: 50 to 100 mg/kg/day orally divided in 4 doses
• Maximum dose: 2 g/day

Comments:

• General dosing recommendations for susceptible infections
• This drug plus an aminoglycoside is the preferred initial regimen for neonates with presumptive early-onset GBS infection.
• Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Septicemia

Neonates:

• Gestational age up to 34 weeks:
• Postnatal age up to 7 days: 100 mg/kg/day IV in equally divided doses every 12 hours
• Postnatal age 8 to 28 days: 150 mg/kg/day IV in equally divided doses every 12 hours
• Gestational age greater than 34 weeks:
• Postnatal age up to 28 days: 150 mg/kg/day IV in equally divided doses every 8 hours

Children: 150 to 200 mg/kg/day IV

Comments:

• Start with IV administration for at least 3 days and continue with the IM route every 3 to 4 hours

Uses: For the treatment of septicemia due to susceptible gram-positive organisms including Streptococcus species, penicillin G-susceptible staphylococci, and enterococci; for the treatment of gram-negative sepsis due to E coli, P mirabilis, and Salmonella species

Usual Pediatric Dose for Meningitis

PARENTERAL:
Neonates:

• Gestational age up to 34 weeks:
• Postnatal age up to 7 days: 100 mg/kg/day IV in equally divided doses every 12 hours
• Postnatal age 8 to 28 days: 150 mg/kg/day IV in equally divided doses every 12 hours
• Gestational age greater than 34 weeks:
• Postnatal age up to 28 days: 150 mg/kg/day IV in equally divided doses every 8 hours

Children: 150 to 200 mg/kg/day IV in equally divided doses every 3 to 4 hours

ORAL: The manufacturer gives no specific dosing instructions.

Comments:

• Therapy may be started with IV administration and continued with IM injections.
• Use with an aminoglycoside may increase efficacy against gram-negative bacteria.

Uses:

• Parenteral: For the treatment of bacterial meningitis due to E coli, group B streptococci, and other gram-negative bacteria (L monocytogenes, N meningitidis)
• Oral: For the treatment of meningitis due to N meningitidis

AAP Recommendations:
1 month or older: 300 to 400 mg/kg/day IV divided in 6 doses
Maximum dose: 12 g/day

IDSA Recommendations for Meningitis:

• Neonates up to 7 days: 150 mg/kg/day IV in divided doses every 8 hours
• Neonates 8 to 28 days: 200 mg/kg/day IV in divided doses every 6 to 8 hours
• Infants and children: 300 mg/kg/day IV in divided doses every 6 hours
• Maximum dose: 12 g/day

Duration of Therapy:

• Aerobic gram-negative bacilli: 21 days
• H influenzae: 7 days
• L monocytogenes: At least 21 days
• N meningitidis: 7 days
• S agalactiae: 14 to 21 days
• S pneumoniae: 10 to 14 days

Comments:

• IDSA: Smaller doses and longer dosing intervals may be prudent for very low-birth weight neonates (less than 2000 g).
• IDSA: Based on presumptive pathogen identification by positive Gram stain: A recommended agent for infection due to L monocytogenes or S agalactiae (use with an aminoglycoside should be considered); recommended as an alternative agent for infection due to N meningitidis
• In children, this drug is added to the standard therapeutic regimen of cefotaxime or ceftriaxone plus vancomycin when L monocytogenes is considered and to an aminoglycoside if a gram-negative enteric pathogen is of concern.
• IDSA: Based on isolated pathogen and susceptibility testing: Considered standard therapy for S pneumoniae or N meningitidis infection with penicillin MIC less than 0.1 mcg/mL, beta-lactamase negative H influenzae, and (with gentamicin) ampicillin-susceptible Enterococcus species; recommended as alternative therapy for infection due to E coli and other Enterobacteriaceae
• Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Meningitis - Streptococcus Group B

AAP Recommendations for GBS Meningitis:

• Infants 7 days or younger: 200 to 300 mg/kg/day IV in 3 divided doses
• Infants older than 7 days: 300 mg/kg/day IV in 4 divided doses

Duration of therapy (uncomplicated meningitis): 14 days

Comments:

• Longer duration of therapy may be needed for patients with prolonged or complicated infections.
• With an aminoglycoside or cefotaxime, recommended for empirical therapy of late-onset meningitis
• Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Endocarditis

The manufacturer gives no specific dosing instructions.

Comments:

• Endocarditis due to enterococcal strains generally responds to IV therapy.
• Use with an aminoglycoside may enhance efficacy when treating streptococcal endocarditis.

Use (parenteral): For the treatment of endocarditis due to susceptible gram-positive organisms including Streptococcus species, penicillin G-susceptible staphylococci, and enterococci

AAP Recommendations for Endocarditis:
1 month or older: 300 to 400 mg/kg/day IV divided in 6 doses
Maximum dose: 12 g/day

AHA Recommendations:
1 year or older: 200 to 300 mg/kg/day IV divided every 4 to 6 hours
Maximum dose: 12 g/day
Duration of therapy: At least 4 to 6 weeks

Comments:

• AHA: Recommended as a preferred (with gentamicin) or alternative (with ceftriaxone) regimen for infective endocarditis due to streptococci relatively resistant to penicillin (includes enterococci and less susceptible viridans streptococci)
• AHA: With an aminoglycoside, recommended as an alternative regimen for infective endocarditis due to HACEK group (for susceptible organisms)
• Maximum daily dose or adult dose should not be exceeded.
• Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Pharyngitis

Parenteral:

• Less than 40 kg: 25 to 50 mg/kg/day IM or IV in equally divided doses every 6 to 8 hours
• At least 40 kg: 250 to 500 mg IM or IV every 6 hours

Oral:

• Up to 20 kg: 50 mg/kg/day orally in equally divided doses every 6 to 8 hours
• Greater than 20 kg: 250 mg orally every 6 hours

Comments:

• Pediatric doses should not exceed recommended adult doses.

Uses:

• Parenteral: For the treatment of respiratory tract infections due to S pneumoniae, S aureus (penicillinase and non-penicillinase producing), H influenzae, and group A beta-hemolytic streptococci
• Oral: For the treatment of respiratory tract infections due to non-penicillinase-producing H influenzae and staphylococci, and streptococci (including S pneumoniae)

Usual Pediatric Dose for Sinusitis

Parenteral:

• Less than 40 kg: 25 to 50 mg/kg/day IM or IV in equally divided doses every 6 to 8 hours
• At least 40 kg: 250 to 500 mg IM or IV every 6 hours

Oral:

• Up to 20 kg: 50 mg/kg/day orally in equally divided doses every 6 to 8 hours
• Greater than 20 kg: 250 mg orally every 6 hours

Comments:

• Pediatric doses should not exceed recommended adult doses.

Uses:

• Parenteral: For the treatment of respiratory tract infections due to S pneumoniae, S aureus (penicillinase and non-penicillinase producing), H influenzae, and group A beta-hemolytic streptococci
• Oral: For the treatment of respiratory tract infections due to non-penicillinase-producing H influenzae and staphylococci, and streptococci (including S pneumoniae)

Usual Pediatric Dose for Upper Respiratory Tract Infection

Parenteral:

• Less than 40 kg: 25 to 50 mg/kg/day IM or IV in equally divided doses every 6 to 8 hours
• At least 40 kg: 250 to 500 mg IM or IV every 6 hours

Oral:

• Up to 20 kg: 50 mg/kg/day orally in equally divided doses every 6 to 8 hours
• Greater than 20 kg: 250 mg orally every 6 hours

Comments:

• Pediatric doses should not exceed recommended adult doses.

Uses:

• Parenteral: For the treatment of respiratory tract infections due to S pneumoniae, S aureus (penicillinase and non-penicillinase producing), H influenzae, and group A beta-hemolytic streptococci
• Oral: For the treatment of respiratory tract infections due to non-penicillinase-producing H influenzae and staphylococci, and streptococci (including S pneumoniae)

Usual Pediatric Dose for Bronchitis

Parenteral:

• Less than 40 kg: 25 to 50 mg/kg/day IM or IV in equally divided doses every 6 to 8 hours
• At least 40 kg: 250 to 500 mg IM or IV every 6 hours

Oral:

• Up to 20 kg: 50 mg/kg/day orally in equally divided doses every 6 to 8 hours
• Greater than 20 kg: 250 mg orally every 6 hours

Comments:

• Pediatric doses should not exceed recommended adult doses.

Uses:

• Parenteral: For the treatment of respiratory tract infections due to S pneumoniae, S aureus (penicillinase and non-penicillinase producing), H influenzae, and group A beta-hemolytic streptococci
• Oral: For the treatment of respiratory tract infections due to non-penicillinase-producing H influenzae and staphylococci, and streptococci (including S pneumoniae)

Usual Pediatric Dose for Pneumonia

Parenteral:

• Less than 40 kg: 25 to 50 mg/kg/day IM or IV in equally divided doses every 6 to 8 hours
• At least 40 kg: 250 to 500 mg IM or IV every 6 hours

Oral:

• Up to 20 kg: 50 mg/kg/day orally in equally divided doses every 6 to 8 hours
• Greater than 20 kg: 250 mg orally every 6 hours

Comments:

• Pediatric doses should not exceed recommended adult doses.

Uses:

• Parenteral: For the treatment of respiratory tract infections due to S pneumoniae, S aureus (penicillinase and non-penicillinase producing), H influenzae, and group A beta-hemolytic streptococci
• Oral: For the treatment of respiratory tract infections due to non-penicillinase-producing H influenzae and staphylococci, and streptococci (including S pneumoniae)

IDSA and Pediatric Infectious Diseases Society (PIDS) Recommendations:
Infants and children older than 3 months:

• Empiric therapy, S pneumoniae with penicillin MICs up to 2 mcg/mL, or beta-lactamase-negative H influenzae: 37.5 to 50 mg/kg IV every 6 hours
• Group A Streptococcus: 50 mg/kg IV every 6 hours
• S pneumoniae resistant to penicillin (MICs at least 4 mcg/mL): 75 to 100 mg/kg IV every 6 hours

Comments:

• Recommended as preferred parenteral therapy for community-acquired pneumonia due to S pneumoniae with penicillin MICs up to 2 mcg/mL, group A Streptococcus, or beta-lactamase-negative H influenza (typeable [a to f] or non-typeable); recommended for inpatients as a preferred empiric therapy for presumed bacterial pneumonia in fully immunized infants or school-aged children (when minimal local penicillin resistance in invasive pneumococcus strains)
• Recommended as alternative parenteral therapy for community-acquired pneumonia due to S pneumoniae resistant to penicillin (MICs at least 4 mcg/mL)
• Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Skin or Soft Tissue Infection

Less than 40 kg: 25 to 50 mg/kg/day IM or IV in equally divided doses every 6 to 8 hours
At least 40 kg: 250 to 500 mg IM or IV every 6 hours

Comments:

• Pediatric doses should not exceed recommended adult doses.

Use: For the treatment of soft tissue infections

Usual Pediatric Dose for Intraabdominal Infection

Parenteral:

• Less than 40 kg: 50 mg/kg/day IM or IV in equally divided doses every 6 to 8 hours
• At least 40 kg: 500 mg IM or IV every 6 hours

Oral:

• Up to 20 kg: 25 mg/kg orally every 6 hours
• Greater than 20 kg: 500 mg orally every 6 hours

Comments:

• Pediatric doses should not exceed recommended adult doses.
• Frequent bacteriological and clinical assessment needed during therapy (and may be needed for several months afterwards) when treating chronic urinary tract and intestinal infections.
• Severe, chronic, or stubborn infections may require larger doses.

Uses:

• Parenteral: For the treatment of gastrointestinal infections due to Salmonella species (including S typhi) and Shigella species; for the treatment of urinary tract infections due to sensitive strains of E coli and P mirabilis
• Oral: For the treatment of gastrointestinal tract infections due to Shigella, Salmonella species (including S typhi), E coli, P mirabilis, and enterococci; for the treatment of genitourinary tract infections due to E coli, P mirabilis, enterococci, Shigella, Salmonella species (including S typhi)

Usual Pediatric Dose for Shigellosis

Parenteral:

• Less than 40 kg: 50 mg/kg/day IM or IV in equally divided doses every 6 to 8 hours
• At least 40 kg: 500 mg IM or IV every 6 hours

Oral:

• Up to 20 kg: 25 mg/kg orally every 6 hours
• Greater than 20 kg: 500 mg orally every 6 hours

Comments:

• Pediatric doses should not exceed recommended adult doses.
• Frequent bacteriological and clinical assessment needed during therapy (and may be needed for several months afterwards) when treating chronic urinary tract and intestinal infections.
• Severe, chronic, or stubborn infections may require larger doses.

Uses:

• Parenteral: For the treatment of gastrointestinal infections due to Salmonella species (including S typhi) and Shigella species; for the treatment of urinary tract infections due to sensitive strains of E coli and P mirabilis
• Oral: For the treatment of gastrointestinal tract infections due to Shigella, Salmonella species (including S typhi), E coli, P mirabilis, and enterococci; for the treatment of genitourinary tract infections due to E coli, P mirabilis, enterococci, Shigella, Salmonella species (including S typhi)

Usual Pediatric Dose for Urinary Tract Infection

Parenteral:

• Less than 40 kg: 50 mg/kg/day IM or IV in equally divided doses every 6 to 8 hours
• At least 40 kg: 500 mg IM or IV every 6 hours

Oral:

• Up to 20 kg: 25 mg/kg orally every 6 hours
• Greater than 20 kg: 500 mg orally every 6 hours

Comments:

• Pediatric doses should not exceed recommended adult doses.
• Frequent bacteriological and clinical assessment needed during therapy (and may be needed for several months afterwards) when treating chronic urinary tract and intestinal infections.
• Severe, chronic, or stubborn infections may require larger doses.

Uses:

• Parenteral: For the treatment of gastrointestinal infections due to Salmonella species (including S typhi) and Shigella species; for the treatment of urinary tract infections due to sensitive strains of E coli and P mirabilis
• Oral: For the treatment of gastrointestinal tract infections due to Shigella, Salmonella species (including S typhi), E coli, P mirabilis, and enterococci; for the treatment of genitourinary tract infections due to E coli, P mirabilis, enterococci, Shigella, Salmonella species (including S typhi)

Usual Pediatric Dose for Typhoid Fever

Parenteral:

• Less than 40 kg: 50 mg/kg/day IM or IV in equally divided doses every 6 to 8 hours
• At least 40 kg: 500 mg IM or IV every 6 hours

Oral:

• Up to 20 kg: 25 mg/kg orally every 6 hours
• Greater than 20 kg: 500 mg orally every 6 hours

Comments:

• Pediatric doses should not exceed recommended adult doses.
• Frequent bacteriological and clinical assessment needed during therapy (and may be needed for several months afterwards) when treating chronic urinary tract and intestinal infections.
• Severe, chronic, or stubborn infections may require larger doses.

Uses:

• Parenteral: For the treatment of gastrointestinal infections due to Salmonella species (including S typhi) and Shigella species; for the treatment of urinary tract infections due to sensitive strains of E coli and P mirabilis
• Oral: For the treatment of gastrointestinal tract infections due to Shigella, Salmonella species (including S typhi), E coli, P mirabilis, and enterococci; for the treatment of genitourinary tract infections due to E coli, P mirabilis, enterococci, Shigella, Salmonella species (including S typhi)

Usual Pediatric Dose for Gastroenteritis

Parenteral:

• Less than 40 kg: 50 mg/kg/day IM or IV in equally divided doses every 6 to 8 hours
• At least 40 kg: 500 mg IM or IV every 6 hours

Oral:

• Up to 20 kg: 25 mg/kg orally every 6 hours
• Greater than 20 kg: 500 mg orally every 6 hours

Comments:

• Pediatric doses should not exceed recommended adult doses.
• Frequent bacteriological and clinical assessment needed during therapy (and may be needed for several months afterwards) when treating chronic urinary tract and intestinal infections.
• Severe, chronic, or stubborn infections may require larger doses.

Uses:

• Parenteral: For the treatment of gastrointestinal infections due to Salmonella species (including S typhi) and Shigella species; for the treatment of urinary tract infections due to sensitive strains of E coli and P mirabilis
• Oral: For the treatment of gastrointestinal tract infections due to Shigella, Salmonella species (including S typhi), E coli, P mirabilis, and enterococci; for the treatment of genitourinary tract infections due to E coli, P mirabilis, enterococci, Shigella, Salmonella species (including S typhi)

Usual Pediatric Dose for Bacterial Endocarditis Prophylaxis

AHA Recommendations:

• Children: 50 mg/kg IM or IV as a single dose 30 to 60 minutes before procedure

Maximum dose: 2 g/dose

Comments:

• Recommended for patients unable to take oral medication
• Antibiotic prophylaxis may be used for dental procedures (involving manipulation of gingival tissues or periapical region of teeth or perforation of oral mucosa), respiratory tract procedures, or procedures on infected skin, skin structures, or musculoskeletal tissue only for patients with the highest risk of infective endocarditis.
• Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Surgical Prophylaxis

ASHP, IDSA, SIS, and SHEA Recommendations: 50 mg/kg IV as a single dose
Maximum dose: 2 g/dose

Redosing interval (from start of preoperative dose): 2 hours

Comments:

• With cefotaxime, a recommended regimen for surgical prophylaxis in patients undergoing liver transplantation
• This drug should be started within 60 minutes before surgical incision.
• A single prophylactic dose is usually sufficient; if prophylaxis is continued postoperatively, duration should be less than 24 hours.
• To ensure adequate serum and tissue drug levels, readministration may be needed if the procedure duration exceeds the recommended redosing interval.
• Redosing may be needed if drug half-life is shortened (e.g., extensive burns) or if prolonged/excessive bleeding during surgery; redosing may not be needed if drug half-life is prolonged (e.g., renal dysfunction).
• Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Peritonitis

ISPD Recommendations:
PROPHYLAXIS: 50 mg/kg IM or IV as a single dose 30 to 60 minutes before procedure
Maximum dose: 2 g/dose

TREATMENT:
Continuous:

• Maintenance dose: 125 mg/L intraperitoneally

Comments:

• Recommended as antibacterial prophylaxis in PD patients for invasive dental procedures (manipulation of gingival tissue or periapical region of teeth, or perforation of oral mucosa)
• Recommended for the treatment of PD-related peritonitis
• Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Inhalation Bacillus anthracis

AAP Recommendations:
Up to 4 weeks of age:

• Gestational age 32 to 34 weeks, up to 1 week of age: 100 mg/kg/day IV in divided doses every 12 hours
• Gestational age 32 to 34 weeks, 1 to 4 weeks of age: 150 mg/kg/day IV in divided doses every 8 hours
• Gestational age 34 to 37 weeks and term neonate, up to 1 week of age: 150 mg/kg/day IV in divided doses every 8 hours
• Gestational age 34 to 37 weeks and term neonate, 1 to 4 weeks of age: 200 mg/kg/day IV in divided doses every 6 hours

1 month or older:

• Systemic anthrax when meningitis has been excluded: 200 mg/kg/day IV in divided doses every 6 hours
• Systemic anthrax with possible/confirmed meningitis: 400 mg/kg/day IV in divided doses every 6 hours

Maximum dose: 3 g/dose

Duration of therapy:

• Severe anthrax (up to 4 weeks of age): At least 2 to 3 weeks or until patient is clinically stable (whichever is longer)
• Systemic anthrax with possible/confirmed meningitis (1 month or older): At least 2 to 3 weeks or until patient is clinically stable (whichever is longer)
• Systemic anthrax when meningitis has been excluded (1 month or older): At least 14 days or until patient is clinically stable (whichever is longer)

Comments:

• Recommended as an alternative agent for the treatment of systemic/severe anthrax due to penicillin-susceptible strains
• Recommended for use with a protein synthesis inhibitor when used for systemic anthrax; the addition of a bactericidal fluoroquinolone is recommended with possible/confirmed meningitis.
• Systemic/severe anthrax includes anthrax meningitis, inhalation anthrax, injection anthrax, gastrointestinal anthrax, and cutaneous anthrax with systemic involvement, extensive edema, or lesions of the head or neck.
• Patients will require prophylaxis to complete an antimicrobial regimen of up to 60 days from onset of illness.
• Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Cutaneous Bacillus anthracis

AAP Recommendations:
Up to 4 weeks of age:

• Gestational age 32 to 34 weeks, up to 1 week of age: 100 mg/kg/day IV in divided doses every 12 hours
• Gestational age 32 to 34 weeks, 1 to 4 weeks of age: 150 mg/kg/day IV in divided doses every 8 hours
• Gestational age 34 to 37 weeks and term neonate, up to 1 week of age: 150 mg/kg/day IV in divided doses every 8 hours
• Gestational age 34 to 37 weeks and term neonate, 1 to 4 weeks of age: 200 mg/kg/day IV in divided doses every 6 hours

1 month or older:

• Systemic anthrax when meningitis has been excluded: 200 mg/kg/day IV in divided doses every 6 hours
• Systemic anthrax with possible/confirmed meningitis: 400 mg/kg/day IV in divided doses every 6 hours

Maximum dose: 3 g/dose

Duration of therapy:

• Severe anthrax (up to 4 weeks of age): At least 2 to 3 weeks or until patient is clinically stable (whichever is longer)
• Systemic anthrax with possible/confirmed meningitis (1 month or older): At least 2 to 3 weeks or until patient is clinically stable (whichever is longer)
• Systemic anthrax when meningitis has been excluded (1 month or older): At least 14 days or until patient is clinically stable (whichever is longer)

Comments:

• Recommended as an alternative agent for the treatment of systemic/severe anthrax due to penicillin-susceptible strains
• Recommended for use with a protein synthesis inhibitor when used for systemic anthrax; the addition of a bactericidal fluoroquinolone is recommended with possible/confirmed meningitis.
• Systemic/severe anthrax includes anthrax meningitis, inhalation anthrax, injection anthrax, gastrointestinal anthrax, and cutaneous anthrax with systemic involvement, extensive edema, or lesions of the head or neck.
• Patients will require prophylaxis to complete an antimicrobial regimen of up to 60 days from onset of illness.
• Current guidelines should be consulted for additional information.

Renal Dose Adjustments

Data not available

Liver Dose Adjustments

Data not available

Dose Adjustments

Larger doses may be required for severe or chronic infections; this applies to all patients, irrespective of age and weight.

Precautions

CONTRAINDICATIONS:

• History of hypersensitivity to any of the penicillins
• Oral: Infections due to penicillinase-producing organisms

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Comments:

• In patients with renal dysfunction, ampicillin-class antibacterials can be removed via hemodialysis but not peritoneal dialysis.

Other Comments

Administration advice:

• Parenteral: Reserve this formulation for moderately severe and severe infections and for patients unable to take oral formulations; may switch to oral formulation as soon as appropriate
• Parenteral: May administer IM or IV (direct IV use [slowly over at least 10 to 15 minutes] or IV drip [the manufacturer product information should be consulted for rate of infusion]); administer IM and IV injections within 1 hour after preparation.
• Oral: Administer with 8 ounces of water, 30 minutes before or 2 hours after meals.
• Do not use oral formulations for initial treatment of severe or life-threatening infections.
• Do not use smaller doses than those recommended.
• Treat all infections for at least 48 to 72 hours after the patient becomes asymptomatic or proof of bacterial eradication has been obtained.
• Treat any infection due to group A beta-hemolytic streptococci for at least 10 days to help prevent acute rheumatic fever or acute glomerulonephritis.
• Limit oral administration to neonates and young infants to the lowest dose compatible with an effective therapeutic regimen; the incompletely developed renal function in such patients may delay elimination of penicillins.

Storage requirements:

• Parenteral: The manufacturer product information should be consulted.
• Oral: Store the reconstituted oral suspension in a refrigerator; discard any unused portion after 14 days.

Reconstitution/preparation techniques:

• The manufacturer product information should be consulted.

IV compatibility:

• Compatible: Sterile Water for Injection, USP; Bacteriostatic Water for Injection, USP; 0.9% Sodium Chloride Injection, USP; 5% Dextrose Injection, USP; 5% Dextrose and 0.45% Sodium Chloride Injection, USP; Lactated Ringers Injection, USP

General:

• This drug is for the treatment of infections due to susceptible strains of the designated bacteria.
• To reduce the development of drug-resistant organisms and maintain effective therapy, antibiotics should be used only to treat or prevent infections proven or strongly suspected to be caused by susceptible bacteria.
• Culture and susceptibility information should be considered when selecting/modifying antibacterial therapy or, if no data are available, local epidemiology and susceptibility patterns may be considered when selecting empiric therapy.
• Bacteriologic studies are recommended to determine the causative organisms and their susceptibility to this drug; therapy may be started before the results of susceptibility testing.
• Stubborn infections may require several weeks of therapy.

Monitoring:

• Gastrointestinal: Frequent bacteriologic and clinical appraisal with chronic gastrointestinal infections (needed during therapy and may be needed for several months afterwards).
• General: Bacteriologic studies/susceptibility testing; organ system function assessment, including renal, hepatic, and hematopoietic (during prolonged therapy and with high dose regimens); darkfield examinations in gonorrhea patients with suspected primary syphilis lesion (prior to therapy); serological tests for syphilis in all gonorrhea patients where concomitant syphilis is suspected (at diagnosis and monthly for at least 4 months).
• Genitourinary: Frequent bacteriologic and clinical appraisal with chronic urinary infections (needed during therapy and may be needed for several months afterwards); follow-up cultures from original infection site(s) (7 to 14 days after gonorrhea therapy); culture test-of-cure from endocervical and anal canals in women (after gonorrhea therapy).
• Hematologic: Organ system function assessment, including hematopoietic (during prolonged therapy and with high dose regimens).
• Hepatic: Organ system function assessment, including hepatic (during prolonged therapy and with high dose regimens).
• Renal: Organ system function assessment, including renal (during prolonged therapy and with high dose regimens).

Patient advice:

• Avoid missing doses and complete the entire course of therapy.
• Oral: Discontinue this drug and contact physician at once if any side effect occurs.
• Oral: If diabetic, consult physician before changing diet or dose of diabetes medication.
• Consult physician at once if watery and bloody stools (with or without stomach cramps and fever) develop.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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