ampicillin

Drug Name

Generic Name: ampicillin, ampicillin sodium

Brand Name:  Ampicin (CAN), Apo-Ampi (CAN), Novo-Ampicillin (CAN), Nu-Ampi (CAN), Penbritin (CAN), Principen

Classification: Antibiotic, Penicillin

Pregnancy Category B

Dosage & route
  • Maximum recommended dosage, 8–14 g/day (reserve 14 g for serious infections, such as meningitis, septicemia); may be given IV, IM, or PO. Use parenteral routes for severe infections; switch to oral route as soon as possible.

ADULTS

  • Prevention of bacterial endocarditis for GI or GU surgery or instrumentation: 2 g ampicillin IM or IV with gentamicin 1.5 mg/kg IM or IV within 30 minutes of starting procedure. Six hours later, give 1 g ampicillin IM or IV or 1 g amoxicillin PO.
  • Prevention of bacterial endocarditis for dental, oral, or upper respiratory procedures: 2 g ampicillin IM or IV within 30 minutes of procedure.
  • STDs in pregnant women and patients allergic to tetracycline: 3.5 g ampicillin PO with 1 g probenecid.
  • Prophylaxis in cesarean section: Single IV or IM dose of 25–100 mg/kg immediately after cord is clamped.

ADULTS AND PEDIATRIC PATIENTS

  • Respiratory and soft-tissue infections:
    • > 40 kg: 250–500 mg IV or IM q 6 hr.
    • < 40 kg: 25–50 mg/kg/day IM or IV in equally divided doses at 6–8 hr intervals.
    • > 20 kg: 250 mg PO q 6 hr.
    • < 20 kg: 50 mg/kg/day PO in equally divided doses q 6–8 hr.
  • GI and GU infections, including women with N. gonorrhoeae:
    • > 40 kg: 500 mg IM or IV q 6 hr.
    • < 40 kg: 50–100 mg/kg/day IM or IV in equally divided doses q 6–8 hr.
    • > 20 kg: 500 mg PO q 6 hr.
    • < 20 kg: 100 mg/kg/day PO in equally divided doses q 6–8 hr.
  • Gonococcal infections: 500 mg q 6 hr for penicillin-sensitive organism or for patients > 45 kg, single dose of 3.5 g PO with 1 g probenecid.
  • Bacterial meningitis: 150–200 mg/kg/day by continuous IV drip and then IM injections in equally divided doses q 3–4 hr.
  • Septicemia: 150–200 mg/kg/day IV for at least 3 days, then IM q 3–4 hr.

PEDIATRIC PATIENTS

  • Prevention of bacterial endocarditis for GI or GU surgery or instrumentation: 50 mg/kg ampicillin IM or IV with 1.5 mg/kg gentamicin IM or IV within 30 minutes of procedure. Six hours later give 25 mg/kg ampicillin IM or IV or 25 mg/kg amoxicillin PO.
  • Prevention of bacterial endocarditis for dental, oral, or upper respiratory procedures: 50 mg/kg ampicillin IM or IV within 30 minutes of procedure.
Therapeutic actions
  • Bactericidal action against sensitive organisms; inhibits synthesis of bacterial cell wall, causing cell death.
Indications
  • Treatment of infections caused by susceptible strains of Shigella, Salmonella, Escherichia coli, Haemophilus influenzae, Proteus mirabilis, Neisseria gonorrhoeae, enterococci, gram-positive organisms (penicillin G–sensitive staphylococci, streptococci, pneumococci)
  • Meningitis caused by Neisseria meningitidis
  • Unlabeled use: Prophylaxis in cesarean section in certain high-risk patients
Adverse effects
  • CNS: Lethargy, hallucinations, seizures
  • CV: CHF
  • GI: Glossitis, stomatitis, gastritis, sore mouth, furry tongue, black “hairy” tongue, nausea, vomiting, diarrhea, abdominal pain, bloody diarrhea, enterocolitis, pseudomembranous colitis, nonspecific hepatitis
  • GU: Nephritis
  • Hematologic: Anemia, thrombocytopenia, leukopenia, neutropenia, prolonged bleeding time
  • Hypersensitivity: Rash, fever, wheezing, anaphylaxis
  • Local: Pain, phlebitis, thrombosis at injection site (parenteral)
  • Other: Superinfections—oral and rectal moniliasis, vaginitis
Contraindications and cautions
  • Contraindicated with allergies to penicillins, cephalosporins, or other allergens.
  • Use cautiously with renal disorders.
Nursing considerations
Assessment
  • History: Allergies to penicillins, cephalosporins, or other allergens; renal disorders; lactation
  • Physical: Culture infected area; skin color, lesion; R, adventitious sounds; bowel sounds; CBC, LFTs, renal function tests, serum electrolytes, Hct, urinalysis
Interventions
  • Culture infected area before treatment; reculture area if response is not as expected.
  • Check IV site carefully for signs of thrombosis or drug reaction.
  • Do not give IM injections in the same site; atrophy can occur. Monitor injection sites.
  • Administer oral drug on an empty stomach, 1 hr before or 2 hr after meals with a full glass of water; do not give with fruit juice or soft drinks.
Teaching points
  • Take this drug around-the-clock.
  • Take the full course of therapy; do not stop taking the drug if you feel better.
  • Take the oral drug on an empty stomach, 1 hour before or 2 hours after meals; do not take with fruit juice or soft drinks; the oral solution is stable for 7 days at room temperature or 14 days refrigerated.
  • This antibiotic is specific to your problem and should not be used to self-treat other infections.
  • You may experience these side effects: Nausea, vomiting, GI upset (eat frequent small meals), diarrhea.
  • Report pain or discomfort at sites, unusual bleeding or bruising, mouth sores, rash, hives, fever, itching, severe diarrhea, difficulty breathing.