Ampicillin / Sulbactam Dosage

Medically reviewed by Drugs.com. Last updated on Oct 30, 2023.

Usual Adult Dose for Skin or Soft Tissue Infection

1.5 to 3 g IV or IM every 6 hours

Comments:

• The dose is expressed as the total of ampicillin content plus sulbactam content (in a constant 2:1 ratio).

Uses: For the treatment of skin and skin structure infections due to susceptible, beta-lactamase-producing strains of Staphylococcus aureus, Escherichia coli, Klebsiella species (including K pneumoniae), Proteus mirabilis, Bacteroides fragilis, Enterobacter species, Acinetobacter calcoaceticus

Infectious Diseases Society of America (IDSA) Recommendations:

• Incisional surgical site infection: 3 g IV every 6 hours
• Infection after animal bite: 1.5 to 3 g IV every 6 to 8 hours
• Infection after human bite: 1.5 to 3 g IV every 6 hours

Comments:

• This drug plus gentamicin or tobramycin are recommended as a combination regimen for treatment of incisional surgical site infections after intestinal or genitourinary tract surgery.
• The following should be considered when using this drug for an infection after a bite: Some gram-negative rods are resistant; this drug does not provide coverage for methicillin-resistant S aureus (MRSA).

Usual Adult Dose for Skin and Structure Infection

1.5 to 3 g IV or IM every 6 hours

Comments:

• The dose is expressed as the total of ampicillin content plus sulbactam content (in a constant 2:1 ratio).

Uses: For the treatment of skin and skin structure infections due to susceptible, beta-lactamase-producing strains of Staphylococcus aureus, Escherichia coli, Klebsiella species (including K pneumoniae), Proteus mirabilis, Bacteroides fragilis, Enterobacter species, Acinetobacter calcoaceticus

Infectious Diseases Society of America (IDSA) Recommendations:

• Incisional surgical site infection: 3 g IV every 6 hours
• Infection after animal bite: 1.5 to 3 g IV every 6 to 8 hours
• Infection after human bite: 1.5 to 3 g IV every 6 hours

Comments:

• This drug plus gentamicin or tobramycin are recommended as a combination regimen for treatment of incisional surgical site infections after intestinal or genitourinary tract surgery.
• The following should be considered when using this drug for an infection after a bite: Some gram-negative rods are resistant; this drug does not provide coverage for methicillin-resistant S aureus (MRSA).

Usual Adult Dose for Intraabdominal Infection

1.5 to 3 g IV or IM every 6 hours

Comments:

• The dose is expressed as the total of ampicillin content plus sulbactam content (in a constant 2:1 ratio).
• Current guidelines should be consulted for additional information.

Uses: For the treatment of intraabdominal infections due to susceptible, beta-lactamase-producing strains of E coli, Klebsiella species (including K pneumoniae), Bacteroides species (including B fragilis), Enterobacter species

Usual Adult Dose for Bacterial Infection

1.5 to 3 g IV or IM every 6 hours

Comments:

• The dose is expressed as the total of ampicillin content plus sulbactam content (in a constant 2:1 ratio).

Uses: For the treatment of gynecological infections due to susceptible, beta-lactamase-producing strains of E coli, Bacteroides species (including B fragilis)

Usual Adult Dose for Endocarditis

American Heart Association (AHA) and IDSA Recommendations: 3 g IV every 6 hours

Duration of therapy:

• Native or prosthetic valve enterococcal endocarditis due to beta-lactamase-producing strains resistant to penicillin and susceptible to aminoglycoside and vancomycin: 6 weeks; longer than 6 weeks if strain is gentamicin-resistant
• Native and prosthetic valve endocarditis due to HACEK microorganisms: 4 weeks; 6 weeks for endocarditis involving prosthetic cardiac valve or other prosthetic cardiac material
• Culture-negative endocarditis (including Bartonella endocarditis) with native valve: 4 to 6 weeks

Comments:

• The dose is expressed as the total of ampicillin content plus sulbactam content (in a constant 2:1 ratio).
• This drug should be used with gentamicin for treatment of native or prosthetic valve enterococcal endocarditis due to beta-lactamase-producing strains resistant to penicillin and susceptible to aminoglycoside and vancomycin; the strain is unlikely to be susceptible to gentamicin.
• HACEK microorganisms include Haemophilus parainfluenzae, H aphrophilus, Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, and Kingella kingae.
• This drug should be used with gentamicin for treatment of culture-negative endocarditis with native valve.
• Infectious diseases specialist should be consulted for culture-negative endocarditis.
• Current guidelines should be consulted for additional information.

Usual Adult Dose for Sinusitis

IDSA Recommendations for Acute Bacterial Rhinosinusitis:

• Severe infection requiring hospitalization: 1.5 to 3 g IV every 6 hours

Comments:

• The dose is expressed as the total of ampicillin content plus sulbactam content (in a constant 2:1 ratio).
• Recommended as a second-line regimen
• Current guidelines should be consulted for additional information.

Usual Adult Dose for Pelvic Inflammatory Disease

US CDC Recommendations: 3 g IV every 6 hours

Comments:

• The dose is expressed as the total of ampicillin content plus sulbactam content (in a constant 2:1 ratio).
• This drug plus doxycycline are recommended as an alternative parenteral regimen; effective against Chlamydia trachomatis, Neisseria gonorrhoeae, and anaerobes in patients with tubo-ovarian abscess.
• At least 24 hours of direct inpatient observation recommended for patients with tubo-ovarian abscesses.
• Oral therapy can generally be started within 24 to 48 hours after clinical improvement.
• The patient's sexual partner(s) should also be evaluated/treated.
• 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:

• Preoperative dose: 3 g IV or IM once, starting within 60 minutes before surgical incision
• Redosing interval (from start of preoperative dose): 2 hours

Comments:

• The dose is expressed as the total of ampicillin content plus sulbactam content (in a constant 2:1 ratio).
• A single prophylactic dose is usually sufficient; if prophylaxis is continued postoperatively, duration should be less than 24 hours.
• Readministration may be needed to ensure adequate serum and tissue drug levels.
• Drug should be readministered if procedure is longer than the redosing interval (from start of preoperative dose [not from start of surgery]); redosing may also 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).
• Before use, local susceptibility should be reviewed due to increasing resistance of E coli to this drug.
• Coadministration with other agents may be recommended, depending on type of procedure.
• Current guidelines should be consulted for additional information.

Uses: Recommended for surgical prophylaxis for the following procedures:

• Thoracic: Noncardiac procedures (including lobectomy, pneumonectomy, lung resection, thoracotomy); video-assisted thoracoscopic surgery
• Biliary tract: Open procedure; elective, high-risk laparoscopic procedure
• Colorectal
• Head and neck: Clean-contaminated cancer surgery; other clean-contaminated procedures (excluding tonsillectomy, functional endoscopic sinus procedures)
• Hysterectomy: Vaginal or abdominal
• Urologic: Clean without entry into urinary tract involving implanted prosthesis
• Plastic surgery: Clean with risk factors or clean-contaminated

Usual Pediatric Dose for Bacterial Infection

Manufacturer Recommendations:
1 year or older:

• Less than 40 kg: 50 mg/kg (ampicillin component) IV every 6 hours
• At least 40 kg: 1.5 to 3 g IV every 6 hours

Duration of therapy: Should not routinely exceed 14 days

Comments:

• The dose for patients weighing at least 40 kg is expressed as the total of ampicillin content plus sulbactam content (in a constant 2:1 ratio).
• In clinical trials, most children received oral antimicrobials after initial treatment with IV ampicillin-sulbactam.
• The total sulbactam dose should not exceed 4 g/day.

Uses: For the treatment of skin and skin structure infections due to susceptible, beta-lactamase-producing strains of S aureus, E coli, Klebsiella species (including K pneumoniae), P mirabilis, B fragilis, Enterobacter species, A calcoaceticus

American Academy of Pediatrics (AAP) Recommendations:
1 month or older:

• Mild to moderate infection: 25 to 50 mg/kg (ampicillin component) IV every 6 hours

Maximum dose: 4 g/day (ampicillin component)

• Severe infection: 50 mg/kg (ampicillin component) IV every 6 hours

Maximum dose: 8 g/day (ampicillin component)

Comments:

• Recommended as alternative therapy for bacteremia and other serious infections due to methicillin-susceptible, penicillin-resistant S aureus
• IV route recommended for human or animal bite wounds. Since this drug does not provide coverage for MRSA, an additional agent should be considered for severe bite wounds.

Usual Pediatric Dose for Skin and Structure Infection

Manufacturer Recommendations:
1 year or older:

• Less than 40 kg: 50 mg/kg (ampicillin component) IV every 6 hours
• At least 40 kg: 1.5 to 3 g IV every 6 hours

Duration of therapy: Should not routinely exceed 14 days

Comments:

• The dose for patients weighing at least 40 kg is expressed as the total of ampicillin content plus sulbactam content (in a constant 2:1 ratio).
• In clinical trials, most children received oral antimicrobials after initial treatment with IV ampicillin-sulbactam.
• The total sulbactam dose should not exceed 4 g/day.

Uses: For the treatment of skin and skin structure infections due to susceptible, beta-lactamase-producing strains of S aureus, E coli, Klebsiella species (including K pneumoniae), P mirabilis, B fragilis, Enterobacter species, A calcoaceticus

American Academy of Pediatrics (AAP) Recommendations:
1 month or older:

• Mild to moderate infection: 25 to 50 mg/kg (ampicillin component) IV every 6 hours

Maximum dose: 4 g/day (ampicillin component)

• Severe infection: 50 mg/kg (ampicillin component) IV every 6 hours

Maximum dose: 8 g/day (ampicillin component)

Comments:

• Recommended as alternative therapy for bacteremia and other serious infections due to methicillin-susceptible, penicillin-resistant S aureus
• IV route recommended for human or animal bite wounds. Since this drug does not provide coverage for MRSA, an additional agent should be considered for severe bite wounds.

Usual Pediatric Dose for Endocarditis

AHA and IDSA Recommendations:
Native or prosthetic valve enterococcal endocarditis due to beta-lactamase-producing strains resistant to penicillin and susceptible to aminoglycoside and vancomycin: 200 mg/kg (ampicillin content) IV per day in 4 equally divided doses
Maximum dose: 8 g/day (ampicillin content)
Duration of therapy: 6 weeks; longer than 6 weeks if strain is gentamicin-resistant

Native and prosthetic valve endocarditis due to HACEK microorganisms: 200 mg/kg (ampicillin content) IV per day in 4 to 6 equally divided doses
Maximum dose: 8 g/day (ampicillin content)
Duration of therapy: 4 weeks; 6 weeks for endocarditis involving prosthetic cardiac valve or other prosthetic cardiac material

Culture-negative endocarditis (including Bartonella endocarditis) with native valve: 200 mg/kg (ampicillin content) IV per day in 4 to 6 equally divided doses
Maximum dose: 8 g/day (ampicillin content)
Duration of therapy: 4 to 6 weeks

Comments:

• This drug should be used with gentamicin for treatment of native or prosthetic valve enterococcal endocarditis due to beta-lactamase-producing strains resistant to penicillin and susceptible to aminoglycoside and vancomycin; the strain is unlikely to be susceptible to gentamicin.
• HACEK microorganisms include H parainfluenzae, H aphrophilus, A actinomycetemcomitans, C hominis, E corrodens, and K kingae.
• This drug should be used with gentamicin for treatment of culture-negative endocarditis with native valve.
• Infectious diseases specialist should be consulted for culture-negative endocarditis.
• Pediatric dose should not exceed adult dose.
• Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Pelvic Inflammatory Disease

AAP and US CDC Recommendations for Adolescents: 3 g IV every 6 hours

Comments:

• The dose is expressed as the total of ampicillin content plus sulbactam content (in a constant 2:1 ratio).
• This drug plus doxycycline are recommended as an alternative parenteral regimen; effective against C trachomatis, N gonorrhoeae, and anaerobes in patients with tubo-ovarian abscess.
• The patient's sexual partner(s) should also be evaluated/treated.
• Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Sinusitis

IDSA Recommendations for Acute Bacterial Rhinosinusitis in Children:

• Severe infection requiring hospitalization: 50 to 100 mg/kg (ampicillin component) IV every 6 hours

Maximum dose: 8 g/day (ampicillin component)

Comments:

• Recommended as a second-line regimen
• Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Surgical Prophylaxis

ASHP, IDSA, SIS, and SHEA Recommendations:

• Preoperative dose: 50 mg/kg (ampicillin content) IV once, starting within 60 minutes before surgical incision

Maximum dose: 2 g/dose (ampicillin content)

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

Comments:

• A single prophylactic dose is usually sufficient; if prophylaxis is continued postoperatively, duration should be less than 24 hours.
• Readministration may be needed to ensure adequate serum and tissue drug levels.
• Drug should be readministered if procedure is longer than the redosing interval; redosing may also be needed if drug half-life is shortened or if prolonged/excessive bleeding during surgery; redosing may not be needed if drug half-life is prolonged.
• Before use, local susceptibility should be reviewed due to increasing resistance of E coli to this drug.
• Coadministration with other agents may be recommended, depending on type of procedure.
• Pediatric dose should not exceed adult dose.
• Current guidelines should be consulted for additional information.

Uses: Recommended for surgical prophylaxis for the following procedures:

• Thoracic: Noncardiac procedures (including lobectomy, pneumonectomy, lung resection, thoracotomy); video-assisted thoracoscopic surgery
• Biliary tract: Open procedure; elective, high-risk laparoscopic procedure
• Colorectal
• Head and neck: Clean-contaminated cancer surgery; other clean-contaminated procedures (excluding tonsillectomy, functional endoscopic sinus procedures)
• Hysterectomy: Vaginal or abdominal
• Urologic: Clean without entry into urinary tract involving implanted prosthesis
• Plastic surgery: Clean with risk factors or clean-contaminated

Renal Dose Adjustments

CrCl at least 30 mL/min: 1.5 to 3 g IV or IM every 6 to 8 hours
CrCl 15 to 29 mL/min: 1.5 to 3 g IV or IM every 12 hours
CrCl 5 to 14 mL/min: 1.5 to 3 g IV or IM every 24 hours

Comments:

• The dose is expressed as the total of ampicillin content plus sulbactam content (in a constant 2:1 ratio).
• This drug should be dosed less often in patients with renal dysfunction according to the standard practice for ampicillin and consistent with the above recommendations.

Liver Dose Adjustments

Liver dysfunction: Hepatic function should be monitored regularly.
History of cholestatic jaundice/liver dysfunction associated with this drug: Contraindicated

Precautions

Safety and efficacy for the treatment of skin and skin structure infections have not been established in patients younger than 1 year. Safety and efficacy for the treatment of intraabdominal infections have not been established in patients younger than 18 years. Safety and efficacy of IM administration have not been established in patients younger than 18 years.

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Comments: Both components may be removed from circulation by hemodialysis.

Other Comments

Administration advice:

• For IM use: Administer by deep IM injection; use only freshly prepared solutions and administer within 1 hour after preparation.
• For IV use: Administer by slow IV injection over at least 10 to 15 minutes or administer (diluted with 50 to 100 mL compatible diluent) as IV infusion over 15 to 30 minutes; consult the manufacturer product information and administer within the recommended time periods according to package (e.g., glass vial, ADD-Vantage[R] vial), diluent, concentration, and storage temperature.
• Do not exceed total sulbactam dose of 4 g/day.
• Do not use ampicillin antibiotics to treat mononucleosis due to high incidence of skin rashes.
• If concomitant aminoglycoside therapy is indicated, reconstitute and administer each product separately; aminopenicillins inactivate aminoglycosides in vitro.

Storage requirements:

• Prior to reconstitution: Store sterile powder at or below 30C (86F)

Reconstitution/preparation techniques:

• For IM injection: Vials for IM use may be reconstituted with Sterile Water for Injection USP, 0.5% Lidocaine Hydrochloride Injection USP, or 2% Lidocaine Hydrochloride Injection USP; the manufacturer product information should be consulted further guidance.
• For IV use: The manufacturer product information should be consulted.

IV compatibility:

• Compatible diluents for vials, piggyback bottles, pharmacy bulk package: Sterile Water for Injection, 0.9% Sodium Chloride Injection, 5% Dextrose Injection, Lactated Ringer's Injection, M/6 Sodium Lactate Injection, 5% Dextrose in 0.45% Saline, 10% Invert Sugar
• Compatible diluent for ADD-Vantage(R) vials: 0.9% Sodium Chloride Injection USP

General:

• Unless otherwise specified, the dose is expressed as the total of ampicillin content (as the sodium salt) plus sulbactam content (as the sodium salt); the 1.5 g dose corresponds to 1 g ampicillin plus 500 mg sulbactam; the 3 g dose corresponds to 2 g ampicillin plus 1 g sulbactam.
• Culture and susceptibility studies are recommended prior to therapy to isolate and identify infecting organisms and to establish susceptibility to this drug.
• This drug is only indicated for skin and skin structure infections, intraabdominal infections, and gynecological infections; however, infections due to ampicillin-susceptible organisms also respond to this drug due to its ampicillin content; should not need to add another antibacterial for mixed infections caused by ampicillin-susceptible organisms and beta-lactamase-producing organisms susceptible to this drug.

Patient advice:

• Avoid missing doses and complete the entire course of therapy.

Further information

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

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