Ampicillin

C. diff Risk

Low

Oral Bioavailability

NA

Dosing

MeningitisSerious Infection100 mg/kg/dose IV every 8 hr
On day of life 8: change to 75 mg/kg/dose IV every 6 hr100 mg/kg/dose IV q 12 hours.
On day of life 8: change to 50 mg/kg/dose IV q 6 hr

MeningitisSerious Infection75 mg/kg/dose IV every 6 hours.
On day of life 29: change to 100 mg/kg/dose IV every 6 hr50 mg/kg/dose IV q 6 hours.

MeningitisSerious InfectionAmpicillin 100 mg/kg/dose IV every 6 hr
(max 3 grams/dose)50 mg/kg/dose IV every 6 hr
(max 3 grams/dose)

1-2 g IV every 4-6 hr

Meningitis or Endocarditis
2 g IV every 4 hr

Oral
500 mg PO QID

CrCl > 50 ml/minCrCl 10-50 ml/minCrCl < 10 ml/minDialysis (HD)Dialysis (CRRT)1-2 g IV every 4-6 hr1-2 g IV every 6-12 hr2 g IV every 12-24 hr1-2 g IV every 12-24 hr2 g load then 1-2 g IV every 8-12 hr

CrCl > 50 ml/minCrCl 10-50 ml/minCrCl < 10 ml/minDialysis (HD)Dialysis (CRRT)1-2 g IV every 4-6 hr1 g IV every 6-12 hr1 g IV every 12-24 hr1 g IV every 12-24 hr2 g load then 1 g IV every 8-12 hr

General Information

Adverse Effects

Allergy and rash as for all beta-lactams

EBV related rash (not allergy)

Rare: cytopenias, +ve Coombs

Common Usage

Pathogen directed therapy for CNS, intravascular, intraabdominal, urinary and other infections especially Enterococcus and Listeria

Drug Monitoring

Laboratory

  • Periodic renal and hematologic function

Clinical

  • rash or hypersensitivity reaction

Major Interactions

Increased risk of rash with allopurinol

Pharmacology

Antimicrobial class: Aminopenicillin

Pregnancy category: B

Average serum half life: 1 hour

Biliary penetration: Therapeutic

CSF penetration: Therapeutic

Lung penetration: Therapeutic

Urine penetration: Therapeutic